RNCSE 26 (4)

Reports of the National Center for Science Education
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Articles available online are listed below.
Click "Print Edition Contents" link for list of articles in the print edition.

Print Edition Contents: 26 (4)

Reports of the National Center for Science Education
Title: 
Contents
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
2

News

  1. California Schemin'
    Rob Boston
    In Lebec, California, a creationist soccer coach tries a blind-side run, but ends up with a boom ball.
  2. Problems with the Intersession Course
    Eugenie C Scott
    NCSE's executive director describes the scientific and pedagogical flaws of the proposed "philosophy of intelligent design" course in Lebec.
  3. "Critical Analysis" in Ohio: The Return of the Zombie
    Glenn Branch
    The standard that would not die rattles around Ohio's Board of Education.
  4. Evolution Safe, After a Delay, in Michigan
    Glenn Branch
    Despite pressure from creationist lawmakers, the state's board of education stands its ground on evolution.
  5. Legal Troubles Plague Kent Hovind
    Greg Martinez
    The irrepressible "Dr Dino" and his wife are convictedon multiple federal counts of tax evasion.
  6. Updates
    News from California, Texas,Canada, Germany, Kenya, and Poland.

NCSE News

  1. NCSE Welcomes New Staff
    Glenn Branch
    Some new faces you will see and new voices you will hear around the office.
  2. NCSE Thanks You for Your Generous Support
    Recognizing those who have helped NCSE financially.

MEMBERS' PAGES

  1. Ten (Eleven) Things Evolutionists Can Do to Improve Communication
    Randy Olson
    The director of Flock of Dodos gives free advice.
  2. Books: Mystery of Mysteries
    Books that examine evolution and speciation.
  3. NCSE On the Road
    An NCSE speaker may be coming to your neighborhood. Check the calendar here.

ARTICLES

  1. Baraminology: Systematic Discontinuity in Discontinuity Systematics
    Alan Gishlick
    Alan Gishlick introduces the main concepts, definitions, and analytical strategies of the creationist approach to systematics intended to show that the pattern of similarity and diversity among living things is one of separation and uniqueness rather than one of common descent.
  2. ANOPA: "Statistical" Systematics for Young-Earth Creationists
    Dan Bolnick
    Research into "baraminology" uses supposedly superior statistical tools. However, they succeed only in giving a less detailed, less clear view of relationships among organisms.

FEATURES

  1. The Basic Types of Life: Critical Evaluation of a Hybrid Model
    Ulrich Kutschera
    In Europe, the creationist concept of "basic types" of life has made headway with a creationist textbook and even some mainstream scientific publications. Is it productive science or just sterile pseudoscience?
  2. Species, Kinds, and Evolution
    John Wilkins
    In order to study speciation, it helps to know what makes a species. Since living things are a stop-frame in an ongoing evolutionary process, defining a species can be done in various ways ...

MEDIA REVIEW

  1. Review of Cladistics: A Practical Primer on CD-ROM by Peter Skelton and Andrew Smith
    Reviewed by Alan Gishlick

"Critical Analysis" in Ohio

Reports of the National Center for Science Education
Title: 
"Critical Analysis" in Ohio: The Return of the Zombie
Author(s): 
Glenn Branch
NCSE Deputy Director
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
9–11
This version might differ slightly from the print publication.
Like a zombie in a horror film, the "Critical Analysis of Evolution" effort returned to haunt the Buckeye State, despite a series of stakes through its heart. In 2002, Ohio adopted a set of science standards including a requirement that students be able to "describe how scientists continue to investigate and critically analyze aspects of evolutionary theory" (see RNCSE 2002 Sep/Oct; 22 [5]: 4–6). When the indicator was introduced, it was widely feared that it would provide a pretext for the introduction of creationist misrepresentations of evolution. In 2004, those fears proved to be justified, when, over the protests of the state's scientific community, the board adopted a corresponding model lesson plan that clearly sought to instill scientifically unwarranted doubts about evolution (see RNCSE 2004 Jan/Feb; 24 [1]: 5–6, 8–9).

Following the decision in Kitzmiller v Dover and the revelation that the board ignored criticisms of the lesson plan from experts at the Ohio Department of Education, the board reversed its decision, voting in February 2006 to remove the "critical analysis" indicator from the standards and to rescind the lesson plan (see RNCSE 2006 May/Jun; 26 [3]: 7–11). At the same time, however, the board charged its Achievement Committee to "consider whether the deleted model lesson, Benchmark H and Indicator 23 should be replaced by a different lesson, benchmark, and indicator, and if so, to present any recommendation to the entire State Board for adoption." Since it was the Achievement Committee that approved the controversial indicator in the first place, the Columbus Dispatch (2006 Feb 20) remarked ruefully, "Meet the new committee, same as the old committee."

The Achievement Committee, like the board as a whole, was divided over issues concerning evolution education, and thus was expected to take months to decide whether a replacement indicator was necessary. The first development occurred in July. According to the current science standards for the tenth grade, students are expected to be able to "[d]escribe that scientists may disagree about explanations of phenomena, about interpretation of data or about the value of rival theories, but they do agree that questioning response to criticism and open communications are integral to the process of science." At a meeting of the board's Achievement Committee on July 10, 2006, board member Colleen Grady proposed the addition of, "Discuss and be able to apply this in the following areas: global warning; evolutionary theory; emerging technologies and how they may impact society, e.g. cloning or stem-cell research."

The fact that evolution and global warming were the only areas of science cited as examples where scientists disagree was of immediate concern. (A similar pairing occurred in Michigan, where House Bill 5251 called for students to "use the scientific method to critically evaluate scientific theories including, but not limited to, the theories of global warming and evolution"; see RNCSE 2006 May/Jun; 26 [3]: 12–16.) Before the meeting, Steve Rissing, a biology professor at the Ohio State University, told the Columbus Dispatch (2006 Jul 9), "This is so transparent ... These are not controversial areas of science," and in reaction to Grady's proposal, Patricia Princehouse of Ohio Citizens for Science told the Dayton Daily News (2006 Jul 11), "We knew they wouldn't just give up and go home. We didn't think they'd come back so soon."

The Dispatch (2006 Jul 11) reported, "Education Department staff will put Grady's proposal into draft form for consideration at the board's September meeting. It is not clear whether there is enough support among committee members to recommend any proposal to the full board." Meanwhile, the Dispatch (2006 Jul 13), took a strong stand against the proposal on its editorial page, declaring, "This fight should have been dead and buried in February ... But a few dogged members still insist on 'teaching the controversy' about evolution, even though the controversy has been manufactured by disingenuous people who wish to introduce the supernatural into science classrooms. ... These few wily board members are the best possible evidence that evolution exists; their tactics mutate every time the public catches on to what's happening."

As the board's September meeting approached, the Campaign to Defend the Constitution — a new organization "fight[ing] for the separation of church and state, individual freedom, scientific progress, pluralism, and tolerance while respecting people of faith and their right to express their beliefs" — urged supporters of the integrity of science education to lobby school board members to reject Grady's proposal should it be introduced. The Toledo Blade (2006 Sep 7) reported that during a teleconference on September 6, 2006, members of the Campaign described the proposal as "a Trojan horse carrying religion into the science curriculum." The Blade added, "Patricia Princehouse, a lecturer in philosophy and evolutionary biology at Case Western Reserve University, who joined the Campaign to Defend the Constitution group, said treating evolution and other topics as though they are somehow different from the rest of science is a way to sneak creationism back into the science curriculum."

A spokesperson for the Ohio Department of Education told the Blade that no specific topics would be mentioned in a draft of the proposal, and the Akron Beacon-Journal reported (2006 Sep 7), "The nine-page document itself is evolutionary. Earlier this year, a proposal was to encourage debate of specific issues: Evolution, global warming and stem cell research. Now, it encourages students to conduct research and have open discussion in the classroom." Nevertheless, board member Martha Wise (a strong voice for the integrity of science education in Ohio; see RNCSE 2006 May/Jun; 26 [3]: 11) commented that the proposal "is a lot of gobbledygook — it's just another wedge into the teaching of ID in science classes." Lawrence Krauss of Case Western Reserve University worried, "When they teach history, are they going to say some people say the Holocaust never happened?"

The new version of the proposal, now dubbed the "Framework for Teaching Controversial Issues" template, became public before the Achievement Committee's September meeting, and was quickly the subject of — appropriately — a critical analysis of its own. Ohio Citizens for Science issued a statement (available on-line at http://www.ohioscience.org/Controversial_Issues_Response.pdf) regarding the framework, describing it as "incoherent if, as its major proponent has stated, it will have teachers and students 'challenge everything.' It is impossible to challenge everything in each school class; to even attempt such a thing would result in chaos and no learning" (emphasis in original). The statement added, "Clearly the template is in fact the latest step in ongoing efforts to orchestrate a religiously motivated attack on the theory of evolution ... While science relies constantly on genuine critical analysis, it does not use denigrating debate tools based on political propaganda and ill-informed by evidence."

Additionally, Alan Leshner — the chief executive officer of the American Association for the Advancement of Science and the publisher of its journal Science — forcefully criticized the framework in his op-ed for the Akron Beacon-Journal (2006 Sep 11), writing, "ID advocates who in the past were concerned only with critical analysis of evolution are adding scientific concepts they oppose on religious grounds, including embryonic stem cell research, as subjects where the scientific consensus would come under attack in Ohio's classrooms. Although the advocates have crafted their arguments carefully, a critical analysis of their version of critical analysis suggests it's an old product in a new wrapper — and that it poses clear and palpable threats to the education and future of Ohio's children."

At the September 11, 2006, meeting, the Achievement Committee declined to consider the "Controversial Issues" template. James L Craig, co-chair of the committee, said, "We've run out of time," according to a report in the Columbus Dispatch (2006 Sep 12), and peremptorily adjourned the meeting. The decision not to consider the template was surprising, since, as the Dispatch reported, the board received "national attention and thousands of e-mails" concerning it in recent weeks, owing in part to the campaign organized by the Committee to Defend the Constitution. It was speculated that the committee was dragging its heels in the fear that the board would vote against any replacement.

Although the Achievement Committee decided not to consider the framework at its September meeting, the Beacon-Journal (2006 Sep 13) observed that "the issue could come up for a vote at next month's regularly scheduled board meeting" in October. The Dispatch reported (2006 Sep 12), "Privately, several board members say they support an immediate vote so debate can end. The proposals, they say, are unnecessary and divisive and draw attention from more important topics." Meanwhile, the Beacon-Journal (2006 Sep 17) editorially commented, "Continuing this very political debate promises to harm the quality of education for Ohio students."

At the committee's October 9, 2006, meeting, however, the template was not even on the agenda and so "critical analysis" was still alive, despite a reported promise from Craig to kill the "critical analysis" effort. Patricia Princehouse of Ohio Citizens for Science told the Canton Repository (2006 Oct 10), "He sandbagged all of us." Confiding "I really don't care for the template," Craig cited the committee's inability to arrive at a consensus as the reason for the failure to vote on the template. Steve Rissing offered a different explanation: Craig "probably feared he would lose the election if he openly moved the template forward, so he made reassuring noises to scientists while claiming ignorance of the progress the template was making."

On October 10, 2006, the second day of the board of education's monthly meeting, supporters of the integrity of evolution education turned out in force, armed with copies of the Repository's article printed on bright yellow paper to catch the attention of members of the board and those attending the meeting, and prepared to use the public comment period to criticize the board for its inaction. As it happened, however, board member Martha Wise, who led February's effort to remove the "critical analysis" language, proposed to discharge the Achievement Committee from any further responsibilities concerning possible replacements from that language. Seconded by Rob Hovis, the motion passed 14–3.

After the vote, Wise told the Columbus Dispatch (2006 Oct 11), "It was time to move on." Princehouse thanked the board, saying, "I'm deeply impressed by the leadership and courage of the board with making a clean break from creationism." Similarly, the Dispatch seemed to assume that the controversy over evolution education in Ohio was finally over, headlining its story, "State education board drops evolution debate," and describing the board as having "pulled the plug on its seemingly incessant debate over Darwin's theory of evolution." But the zombie may not be out of action yet: angered by the board's vote, Achievement Committee co-chair Michael Cochran assured the Dispatch, "I will guarantee you that as long as I am chair [sic] of the committee, it's gonna be on the agenda next month."

About the Author(s): 
Glenn Branch
NCSE
PO Box 9477
Berkeley CA 94709-0477
branch@ncseweb.org

Baraminology

Reports of the National Center for Science Education
Title: 
Baraminology
Author(s): 
Alan Gishlick
Gustavus Adolphus College
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
17–21
This version might differ slightly from the print publication.
Creation science comes as a surprise to many scientists, and thus I suspect that the fact that there is creationist systematics will come as an even bigger surprise to systematists. Yet creationists do practice a form of systematics, called "baraminology", and for creationist science it is surprisingly rigorous and internally consistent. It employs terminology and methodology not wholly unfamiliar to mainstream systematists (see sidebar, p 21).

The term "baraminology" comes from baramin, which was constructed from the Hebrew root words bara (created) and min (kind) by creationist Frank L Marsh (1941). Baraminology has also been referred to as "discontinuity systematics" (ReMine 1990; Marsh 1941, 1976). Baraminologists consider the baramin to be a taxonomic rank corresponding to the "created kinds" of Genesis. "Intelligent design" creationists are interested in baraminology as a way of quantifying discontinuities in the tree of life (Scherer 1993, 1998; Hartwig-Scherer 1998) and as a boundary between "macroevolution" and "microevolution" (Scherer 1993, 1998), although they tend to shun the term baramin and prefer the term "basic type" (Scherer 1993; Hartwig-Scherer 1998), perhaps because it avoids religious implications. It is also used as a proof of the actions of a designer or special creator (ReMine 1993; Scherer 1998).

The basic idea behind discontinuity systematics is that there are boundaries in the history of life that cannot be crossed. The aim is to find the "discontinuities" in the history of life, or the limits of common ancestry (ReMine 1993). While Marsh may have originated discontinuity systematics in the 1940s, it has been updated and refined to a form that is rapidly becoming one of the most active areas of creationist "scientific" research, and some of its methodology has been applied in near-mainstream research (for example, Scherer 1993). This area of research is also one of the places where "intelligent design" creationist and young-earth creationist "research" overlap.

What is most amazing is the number of traditional systematic methods and terminology that are employed by baraminologists. While they use many of the same methods as most systematists, from cladistics to the Analysis of Pattern (ANOPA) method, they use these tools to identify the "gaps", rather than the connections in life as most systematists do. This is why baraminologists principally employ phenetic methods of Sokal and Sneath (1963) — which are based on overall similarities in appearance or general features — computing distance matrices for a group of taxa and producing character mismatch statistics based on the matching coefficient of Sokal and Michener (1958). They see phenetics as useful in determining the biological gaps.

In addition, baraminologists employ cladistics for determining intra-holobaraminic relationships, as well as homoplasy (similarity in form not attributed to common descent) for separate groups (Robinson and Cavanaugh 1998a). Baraminologists recognize synapomorphy (shared features that are attributed to common descent) as an example both of a feature that unites a holobaramin, and also of a "discontinuity" among groups. The synapomorphy that diagnoses a group suggests a creative event by God (Wood and others 2003). Baraminologists are very much concerned with having an accurate definition of "kind" because it is vague as commonly used (Awbrey 1981) and because a consistent definition will enable the discovery of the basic created kinds — and ultimately a calculation of the number of animals present on the ark, for young-earth creationists.

Baraminology has had deep roots, but more recently there has been an attempt to codify it into a working method of research for creationist biologists. This culminated in the formation of the Baraminology Study Group (BSG) based at Bryan College in Dayton, Tennessee (http://www.bryancore.org/bsg/index.html). This group has hosted several conferences on baraminology starting in 1997, and has published a book on baraminological methodology called Understanding the Pattern of Life (Wood and others 2003). This book offers a concise and relatively complete explanation of baraminology and its practice.

Baraminological Taxonomy

The role of discontinuity systematics is to establish the boundaries of common descent. To designate their groups and boundaries, baraminologists employ terminology and designations suspiciously similar to that of most systematists, and in particular to Mayr's evolutionary systematics. The baraminological terminology originally codified by ReMine (1993) and expanded upon by Frair (2000) is shown in the sidebar (see p 21).

For baraminologists, these taxonomic designations have different functions. The ultimate goal is to take polybaramins and break them down into their component monobaramins and their respective holobaramins. These holobaramins could then be placed in apobaramins of structurally similar animals. Baraminologists suggest that it is useful to talk about apobaramins because the holobaramins have many similarities that cross holobaraminic boundaries. Apobaramins are considered useful for studying larger groups of morphologically similar animals. Frair (2000) suggests that humans should be compared with the group most structurally and functionally similar to them: the great apes. There is a sort of cognitive dissonance going on with apobaramins, in that baraminologists are still using the power of phylogenetic inference, even though they deny phylogeny. If the groups are not phylogenetically related, why should baraminologists expect them to be comparable?

Once holobaramins have been determined, the phylogenetic relationships of the in-group members of a baramin could be worked out (Frair 2000). However, baraminologists do not think that displaying these relationships in the forms of trees would be useful. After producing trees, baraminologists have suggested that something other than trees may be more informative for depicting relationships; they suggest that other schemes, such as networks, lattices, or pattern recognition projection plots may do a better job (Frair 2000). Apparently, showing trees is a bit to descent-oriented for comfort. This is probably because representing relationships as descent, even within a holobaramin might leave people with the "wrong" impression. If people were to think too much about descent within a holobaramin, they may start to think that it can be extrapolated to apobaramins. However, baraminologists propose a slightly different notion of descent within groups:
[D]ifferent members of a holobaramin could have resulted from a sorting out to the offspring of different genes (DNA) from parental organisms. This is a common occurrence today. Or, since the time of creation there could have been some hereditary modifications of the DNA (mutations), and these were passed on to the diverging offspring. Selection in nature could have influenced the potential for survival of the diverse siblings. (Frair 2000)
Finally, it is interesting to note that baraminologists, like phylogenetic taxonomists, claim to eschew "essentialist" thinking, which seems odd given their notions of limited created "kinds"; however, this is because they recognize that diagnostic baraminological features can be lost through variation within a kind. The result is that combinations of other features in the "kind" are used to unite them in a monobaramin (Wood and others 2003).

Finding the "Discontinuities" of life

Practitioners of discontinuity systematics claim that it carries no model-based assumptions and therefore can be used independently of creation theories. Their claim is that they do not presuppose discontinuities, but rather follow the data to discover discontinuities where they exist (ReMine 1990). In practice, however, this is not the case. Frequently and explicitly, biblical criteria are used when discontinuities fail to be found among groups that "should be" discontinuous, as in the case of humans and chimps in Robinson and Cavanaugh (1998a). Wood and others (2003) explicitly state that the biblical criteria are paramount and that discontinuities are presupposed because of the separate creation events mentioned in the Bible. Thus, baramins may be defined on a number of criteria, but the "scriptural" criterion takes precedence and is the only one necessary. However, because there are no scriptural definitions for much of life, in those cases the other criteria are used.

In these cases, baraminologists use a number of membership criteria to determine the boundaries of the holobaramins. These criteria were first proposed as generalizations by ReMine (1990) and have been fleshed out by subsequent works; however, few have been extensively tested or employed as of yet (Wood and Cavanaugh 2003). Save for the biblical criteria, all measures are considered fallible, and thus proponents argue that multiple criteria should be employed when attempting to diagnose a holobaramin (Wood and Cavanaugh 2003; Wood and others 2003).

Morphological criteria

Baraminologists have spent perhaps the most research time on the morphological criteria.Within these criteria, baraminologists construct measures of baraminological distance corresponding to character mismatches among the features of the groups they are analyzing. To measure baraminological distance, baraminologists employ a wide range of methods for discovering morphological gaps, borrowing traditional methods such as cladistics and phenetics and developing their own methods. In the computation of such units, traditional cladistic consistency measures and phenetic distance measures are used, along with other multivariate statistical methods. Baraminologists are especially enamored of phenetics (as in Sokal and Sneath 1963) because this approach is particularly amenable to a typological view of life (ReMine 1990). Included in morphological criteria are the identification of morphologies, organs, metabolic pathways, cellular processes, or functions that are unique to a group (sometimes considered synapomorphies) and thus supposedly suggestive of separate origins.

In selecting organisms for morphological analysis to divide monobaramins from apobaramins, baraminologists use typical taxonomic procedures. Baraminologists start with a classification, or according to Robinson and Cavanaugh (1998a), a hypothesized phylogeny (which is ironic given their denial of large-scale phylogenetic relationships), because they assume this group would contain truly holobaraminic groups. Animals of closely allied taxonomic groups are selected as in-groups and nearest neighbor groups are selected as out-groups for biological comparability (Robinson and Cavanaugh 1997).

Baraminologists also use cladistic methods. They compute trees using traditional cladistic software. Groups with high correlations within a bootstrapped dataset are considered potentially holobaraminic and then must be tested for phylogenetic discontinuity of their subgroups. High levels of homoplasy are also considered indicative of separate baramins, which baraminologists propose are a result of separate creations.

Baraminologists consider homologies to exist within holobaramins; homoplasies are features shared among holobaramins (Wise 1990). Baraminologists assume that a certain level of homoplasy delineates a phylogenetic discontinuity (Wise 1990), but no discrete criterion has yet been provided. For scriptural reasons, baraminologists think that organisms are too well designed to have true independence of characters (Wood and others 2003), which they argue calls into question the utility of independent character data.

In order to determine the degree of homoplasy, baraminologists compute a "Homoplasy Index" (HI) — the equivalent of 1–CI of traditional cladistic analysis (Kluge and Farris 1969). If the HI is high, then separate baramins are preferred. If the HI is high within a holobaramin, it is proposed to be the result of "gene scattering" from a complex ancestor through hybridization (Robinson and Cavanaugh 1998a; Scherer 1993). As with other baraminological measures, there is no specific measure of what degree of HI represents separate baramins and no explanation of why finding high HIs within a diagnosed holobaramin is not evidence that it is really an apobaramin. Robinson and Cavanaugh (1998a) note that there is a 0 homoplasy index between humans and apes in their dataset, which they suggests speaks to an imperfect measure by that criteria in some circumstances — namely those in which the analysis does not produce the answer they want. Therefore they caution researchers about using the HI as a criterion.

Molecular criteria

Baraminologists have recently become interested in molecular criteria to define a baramin because they offer the chance to search for discontinuities at the "fundamental" level of life (Robinson 1997; but see also Marsh 1971). The reasoning is similar to that of traditional systematists, and baraminology uses some of the same data and analytical techniques. Baraminologists believe that all holobaramins went through a severe bottleneck at the time of the Noachian Flood, so mitochondrial DNA should be an ideal systematic tool (Robinson 1997). Like other systematists, baraminologists download sequences from on-line databases such as GenBank and use typical phylogenetic alignment methods. Baraminologists use taxa that they believe are "phylogenetically distinct" for out-groups in molecular analysis. They then compare sequences by percent sequence difference compared to taxonomic rank, use parsimony distance estimates to construct groupings, and finally evaluate these groupings by bootstrap methods. Molecular methods were pioneered by Robinson (1997) for turtle baraminology. Baraminologists also utilize DNA/DNA hybridization and blood serum reactivity measurements to determine baraminological divisions.

Ecological criteria

The ecological criteria were first proposed by Wise (1992), who argued that ecological and trophic differences reflected separate originations or groups. Wise based this on the idea that the taxonomic rank of family reflected created kinds and his observations that the families tend to contain animals with similar ecologies and trophic levels. Thus, different ecological or trophic features should delineate separate baramins. Wood and others (2003) suggest that this criterion would be most useful for single-celled organisms, citing the radically different ecologies and cellular metabolisms found in bacteria and archaea, which, they argue, suggest separate origins.

Fossil or stratigraphic criteria

This criterion is a bit hard to understand and employ. For young-earth creationist baraminologists, the stratigraphic record is not reflective of the ancestral history of living things, but rather of deposition during the Noachian Flood. Thus the stratigraphic position of organisms should be irrelevant under this model.

Hybridization criteria

Based on the early work of Marsh (1941, 1976), the idea is that the limits of a baramin or basic type can be established for a group of organisms by their ability to hybridize. This is proposed as a testable, definable rank above that of species. It does not matter whether the hybridization is natural, or the offspring is fertile, only that hybridization is possible through some means, including artificial insemination (Scherer 1993). In order to establish these criteria, baraminologists collect and catalog hybrid data, supplemented by some hybridization studies of their own (Scherer and Hilsberg 1982; Scherer 1993). Hybridization potential is correlated with other measures of baraminological distance to test whether groups believed to be monobaraminic are capable of hybridization; if they are, then it provides support for an actual phylogenetic relationship between the organisms (Robinson and Cavanaugh 1998b). One wonders if they are willing to investigate the hybridization criteria for humans and chimps, which was not discussed in Robinson and Cavanaugh (1998a). A hybridization database is available on-line through the website of the BSG (http://www.bryancore.org/hdb/). Hybridization work is one area where practitioners of "intelligent design" and young-earth creationists overlap.

Biblical criteria

The biblical criteria are paramount and trump all other criteria (Wood and others 2003). There are two grades of biblical criteria; the first whether the Bible specifically references the baramin as specially created, and the second whether the Bible implies that it was specially created (Wood and others 2003). There are a number of studies that show how the biblical criteria are employed in baraminological estimates. Robinson (1997) provides a good example for turtles.

First, baraminologists search for any identification of a baramin in biblical texts. In the case of Robinson (1997), it is suggested that turtles are identified in Leviticus. Second, baraminologists determine whether the animal is "clean" or "unclean", thus determining how many pairs were brought onto the Ark. In Robinson (1997), turtles are determined to be unclean; thus only one pair of each turtle baramin would have been required. Robinson also suggests the marine turtles would not have been on the Ark. In the case of humans and primates, Robinson and Cavanaugh (1998a) conclude that even though other criteria cannot separate humans and primates, the biblical criteria specifically states that humans are a separate baramin, so the other data are in effect immaterial.

To aid their quest for discontinuity, baraminologists have developed two semi-original and supposedly objective methodologies, ANOPA and BDIST, which they use along with more traditional systematic methods.

ANOPA

One of the membership criteria proposed by ReMine (1990), the "true lineage" can be considered part of the morphological criterion and the stratigraphic criterion. The idea behind this is that organisms could be represented as discrete points in a three-dimensional morphospace. If organisms could be connected by a continuous lineage in morphospace, then they could be considered part of the same baramin. Analysis of Pattern (ANOPA) is a statistical tool developed by Cavanaugh to determine whether such lineages exist (Cavanaugh and Sternberg 2004). Cavanaugh claims that this method is useful for investigating three-dimensional morphological data quantitatively; however, it appears to differ little from principal components analysis with a fancy graphical display, and its measures are suspect (see Dan Bolnick's analysis of ANOPA, p 22).

BDIST

Baraminologists have developed their own analysis software, which performs a distance analysis similar to that of Sokal and Sneath (1963). This is called BDIST (Wood 2001) and is available for free download at http://www.bryancore.org/bsg/bdist.html. This program is designed to utilize cladistic datasets in NEXUS format as used by PAUP* (Phylogenetic Analysis Using Parsimony; available on-line at http://paup.csit.fsu.edu).

BDIST computes the "coefficient of baraminic distance" as originally described by Robinson and Cavanaugh (1998a). This coefficient is a form of the simple matching coefficient of Sokal and Michener (1958). This baraminic distance represents the percentage of characters two taxa share in common. If there is a "chain of positive and significant baraminic distance correlations" connecting all the taxa, then they are monobaraminic (Robinson and Cavanaugh 1998a). Basically, BDIST computes a phenetic distance matrix.

Overall, however, the BDIST methodology has not been extensively applied, and there is no evidence that the algorithmic effects of large datasets, or the role of missing data, have ever been studied by baraminologists. Baraminologists appear to apply an old phenetic method, without really studying how it works. More interestingly the method might not really work at all. In the published applications of the method so far, in no case did it actually distinguish between two baramins. In cases where it returned results baraminologists could live with, they determined a holobaraminic status for the group. This was the case for felids (Robinson and Cavanaugh 1998b), flaveriinae (Wood and Cavanaugh 2001), and fossil and recent equids (Cavanaugh and others 2003). In conditions where it did not return results favorable to baraminologists, other criteria are applied to achieve the desired result. This was the case for humans and primates (Robinson and Cavanaugh 1998a) where BDIST did not show a separation. Instead, the authors employed ad hoc "ecological criteria" to achieve separate baramins, while not discussing the "biblical criteria".

Baraminology Glossary
The baraminological groups were originally codified by ReMine (1993) and expanded by Frair (2000).

Holobaramin: All known living and extinct forms understood to share genetic relationships. It is the entire group of organisms related by common ancestry. This would correspond to Mayr's (1963) holophyly or Hennig's (1950) monophyly.

Monobaramin: A group containing only organisms related by common descent, but not necessarily all of them. This could be a group containing one entire holobaramin or a portion of it. This would correspond roughly to Mayr's (1963) monophyly or Hennig's (1950) paraphyly.

Apobaramin: A group consisting of one or more holobaramins. The group of holobaramins may share similar morphology, ecology, and function, but, by definition, not common descent. This may be somewhat like polyphyletic groups.

Polybaramin: A grouping of two or more individuals who are part of at least two holobaramins. It may be a combination of holobaramins, monobaramins, apobaramins, and individuals that by definition do not share a common ancestor. This is consistent with traditional notions of polyphyly.

Baraminologists also recognize a number of taxonomic groupings — archaebaramin (the original created individuals of a holobaramin), neobaramin (the extant individuals in a holobaramin), and paleobaramin (the extinct members of a baramin, or a wholly extinct baramin) — that do not have counterparts in traditional systematics.
Only the study on equids (Cavanaugh 2003) included both fossil and living taxa, and none of the other studies contained datasets with missing data. Therefore, this study served as a template to see how they would investigate fossil and recent morphological datasets. In their treatment of the Evander (1989) data for fossil horses, Cavanaugh and others (2003) removed the missing data by recoding it so that "unknown" data were coded as 0, absence as 1, partial derivation as 2, and presence as 3 and 4 (some characters have more than 2 states). The recoding of unknown data to a specific value that can be used in the analysis makes the dataset use all characters; however, it falsely increases the amount of morphological variation by assigning a numerical value to an unknown. In a sense, the authors artificially create a morphological character state where there is none. This only has minor effects on the overall analysis since it only applies to five characters in a single taxon, so recoding the dataset correctly to include the missing data did not significantly alter the results. However, the effects would be more profound in larger datasets with more widely scattered missing data.

The BDIST software, as configured by Wood, screens out any character with less than "95% relevancy". Why this threshold was chosen is not explained, nor how it is determined. Based on investigation of datasets, relevancy appears to be determined by percentage of missing data for a character relative to total number of taxa. This makes the application of this method to fossil datasets difficult. Surprisingly, characters with no variation (either all 0s or 1s) are not considered "irrelevant" (as they would be in cladistic analyses because they would be "uninformative"). The importance of including characters and taxa with missing data has been shown (Donoghue and others 1989). Recoding missing data as valued, as Cavanaugh and others (2003) have done, however, would have a measurable distorting effect on the results, particularly if the amount of missing data was a larger proportion of the dataset.

When the relative baraminic distances are compared with the phylogenies produced by the datasets, the overall result is a steady, gradual trend in decreasing baraminic distance relative to the phylogeny. These results are comparable to those generated from the Evander (1989) data for fossil horses. Thus, with no significant baraminic distance shifts within the datasets, it could be concluded that dinosaurs and birds belong to the same holobaramin. This makes sense in an evolutionary context: the more transitional features one finds in a set of related organisms, the lower the relative distance between any two taxa will be. In general, including more fossil taxa with transitional morphologies will decrease phylogenic discontinuity, which may explain the datasets that baraminologists have analyzed so far.

Conclusion

Despite its use of computer software and flashy statistical graphics, the practice of baraminology amounts to little more than a parroting of scientific investigations into phylogenetics. A critical analysis of the results from the one "objective" software program employed by baraminologists suggests that the method does not actually work. The supremacy of the biblical criteria is explicitly admitted to by Wood and others (2003) in their guidebook to baraminology, so all their claims of "objectivity" notwithstanding, the results will never stray very far from a literal reading of biblical texts. I will give the baraminologists credit in one area: they are up-front about their motives and predispositions and true to their biblical criteria and methodology, which is more than can be said about "intelligent design" proponents.

References



Awbrey FT. 1981. Defining "kinds" — Do creationists apply a double standard? Creation/Evolution 2 (3): 1–6.

Cavanaugh DP, Sternberg RV. 2004. Analysis of morphological groupings using ANOPA, a pattern recognition and multivariate statistical method: A case study involving centrarchid fishes. Journal of Biological Systems 12 (2): 137–67.

Cavanaugh DP, Wood TC, Wise KP. 2003. Fossil Equidae: A monobaraminic, stratomorphic series. In Ivey RL, editor. Proceedings of the Fifth International Conference on Creationism. Pittsburgh: Creation Science Fellowship. p 143–53.

Donoghue MJ, Doyle LA, Gauthier J, Kluge AG, Rowe T. 1989. The importance of fossils in phylogeny reconstruction. Annual Review of Ecology and Systematics 20: 431–60.

Evander R. 1989. Phylogeny of the family Equidae. In: Prothero DR, Schoch RM, editors. The Evolution of Perissodactyls. New York: Oxford University Press. p 109–27.

Frair W. 2000. Baraminology — Classification of created organisms. Creation Research Society Quarterly 37: 82–91.

Hartwig-Scherer S. 1998. Apes or ancestors? Interpretations of the hominid fossil record within evolutionary and basic type biology. In Dembski WA, editor. Mere Creation. Downers Grove (IL): InterVarsity Press. p 212–35.

Kluge AG, Farris S. 1969. Quantitative phyletics and the evolution of anurans. Systematic Zoology 18 (1): 1–32.

Marsh FL. 1941. Fundamental Biology. Lincoln (NE): [self-published].

Marsh FL. 1971. The Genesis kinds in the modern world. In: Lammerts WE, editor. Scientific Studies in Special Creation. Nutley (NJ): Presbyterian and Reformed Publishing. p 136–55.

Marsh FL. 1976. Variation and Fixity in Nature. Mountain View (CA): Pacific Press Publishing Association.

ReMine WJ. 1990. Discontinuity systematics: A methodology of biosystematics relevant to the creation model. In Walsh RE, Brooks CL, editors. Proceedings of the Second International Conference on Creationism. Pittsburgh: Creation Science Fellowship. p 207–13.

ReMine WJ. 1993. The Biotic Message. St Paul (MN): St Paul Science.

Robinson DA. 1997. A mitochondrial DNA analysis of the testudine apobaramin. Creation Research Society Quarterly 33:262–72.

Robinson DA, Cavanaugh DP. 1998a. A quantitative approach to baraminology with examples from the primates. Creation Research Society Quarterly 34: 196–208.

Robinson DA, Cavanaugh DP. 1998b. Evidence for a holobaraminic origin of the cats. Creation Research Society Quarterly 35: 2–14.

Scherer S. 1993. Typen des Lebens. Berlin: Pascal.

Scherer S. 1998. Basic types of life: Evidence of design from taxonomy? In Dembski WA, editor. Mere Creation. Downers Grove (IL): InterVarsity Press. p 195–211.

Scherer VS, Hilsberg T. Hybridisierung und verwandtschaftsgrade innerhalb der Anatidae — eine systematische und evolutionstheoretische Betrachtung. Journal für Ornithologie 123: 357–80.

Sokal RR, Michener CD. 1958. A statistical method for evaluating systematic relationships. University of Kansas Science Bulletin 38: 1409–38.

Sokal RR, Sneath PHA. 1963. Principles of Numerical Taxonomy. San Francisco: WH Freeman.

Wise KP. 1990. Baraminology: A young-earth creation biosystematic method. In: Walsh RE, Brooks CL, editors. Proceedings of the Second International Conference on Creationism. Pittsburgh: Creation Science Fellowship.

Wise KP. 1992. Practical baraminology. Creation ex Nihilo Technical Journal 6 (2): 122–37.

Wood TC. 2001. BDIST software, v. 1.0. Center for Origins Research and Education, Bryan College. Distributed by the author.

Wood TC, Williams PJ, Wise KP, and Robinson DA. 1999. Baraminology of the Camelidae. Baraminology '99, pp. 9–18

Wood TC, Cavanaugh DP. 2001. A baraminological analysis of subtribe Flaveriinae (Asteraceae: Helenieae) and the origin of biological complexity. Origins 52: 7–27.

Wood TC, Cavanaugh DP. 2003. An evaluation of lineages and trajectories as baraminological membership criteria. Occasional Papers of the Baraminological Study Group 1 (1): 1–6.

Wood TC, Wise KP, Murray MJ. 2003. Understanding the Pattern of Life: Origins and Organization of the Species. Nashville (TN): Broadman & Holman Publishing Group.

About the Author(s): 
Alan Gishlick
c/o NCSE
PO Box 9477
Berkeley CA 94709-0477
gish@ncseweb.org

Problems with the Intersession Course

Reports of the National Center for Science Education
Title: 
Problems with the Intersession Course
Author(s): 
Eugenie C Scott
Executive Director, NCSE
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
6–9
This version might differ slightly from the print publication.
NCSE's executive director Eugenie C Scott was asked to write a declaration in support of the plaintiffs' motion for a temporary restraining order, and if necessary a preliminary injunction, in Hurst et al v Newman et al. The following discussion of specific problems with the "Philosophy of Intelligent Design" course that was at issue in the case is taken from her declaration.

Introduction

In my expert opinion, the purpose and effect of the course at issue in this lawsuit are not to present a comparative treatment of the various philosophical issues surrounding evolution and creationism.

Rather, the purpose and effect of the class are to disparage the scientific status of evolution and to present as superior to evolution the religious ideas of creation science and "intelligent design". In other words, the course advocates on behalf of a particular religious view, and a sectarian one at that; special creationism is a minority view in American Christianity.

The evidence on which I base that conclusion pervades the course description, the original syllabus, and the revised syllabus — and turns on four general observations.

Lack of diversity

First, although the revised syllabus for the class asserts that the course will present the "world views on origins," the course does not even begin to provide students with the diversity of viewpoints on this matter. (It is worth noting that among the other intersession classes are a class specifically on "Comparative Religion" and another on "Mythology." The first is truly comparative, covering five major religions, and the second is on ancient myths and their influence on books [and] movies, such as Star Wars. This shows that there is at least an awareness at the school of how to treat religious views in a comparative fashion.) Instead, the course presents a single religious viewpoint, namely creationism (whether as creation science or "intelligent design").

Despite the original course title "Philosophy of Intelligent Design," the original version of the syllabus was dominated by creation science — the same view that the Supreme Court in Edwards held could not be taught in public schools.

The course description, which I understand has remained unchanged, emphasizes creation science by, for example, advocating the belief that there is scientific evidence that "the earth is thousands of years old, not billions." It also states that the course will "take a close look at evolution as a theory and will discuss the scientific, biological, and Biblical aspects that suggest why Darwin's philosophy is not rock solid" (my emphasis).

The revised version of the syllabus emphasizes "intelligent design", but traces of creation science still appear, especially in such course materials as the video Chemicals to Living Cells: Fantasy or Science, which is sold by the creation-science ministry Answers in Genesis.

The syllabi, course description, and course materials make no mention of any non-Western religious viewpoints on the origins of life and its history. In any class purporting to provide a comparative treatment of cultural phenomena, that omission is remarkable. Anthropologists regard origin myths — stories about the ways in which the world and its inhabitants were formed (usually as the work of supernatural beings or forces) — as a cultural universal. There is certainly no shortage of origin myths available for discussion. Yet the course description and the original syllabus here reflect a narrow focus on a particular sectarian account of origins.

Similarly, there is no mention in the course materials of any religious viewpoints, Western or non-Western, that accept evolution. An example of these would be any of the many varieties of Christian theology known as theistic evolution: A number of mainline Christian denominations in the United States regard evolution as no threat to their theological views. For example, a number of prominent religious figures, including the late Pope John Paul II, have expressed the view that evolution is compatible with, or even enriches, their faith. A number of prominent scientists, including Francis Collins (the leader of the Human Genome Project), have made similar claims. But students in this course will not learn about any of these views. Instead, they will be told that evolution and religion are involved in (in the words of one of the videos on the original syllabus) a "War of the Worldviews".

The absence of the viewpoints of other religious traditions from the course materials belies any claim that the course's aim is to present a balanced, comparative, or objective treatment. Moreover, since the only religious viewpoint presented is in opposition to evolution, the effect is to present evolution as intrinsically antireligious. The course thus employs the "two-model" approach (beloved of proponents of creation science and "intelligent design") that Judge Overton aptly described in the McLean case as a "contrived dualism."

Bias in the course materials

Second, the course materials make clear that the class is being taught from an anti-evolution, pro-creationist and pro-"intelligent design" perspective.

The course description promises that the course will present evidence that "Darwin's philosophy is not rock solid" and present evidence "suggesting the earth is thousands of years old, not billions," thereby plainly reflecting a manifestly pro-creationist perspective. Furthermore, the course description's reference to treatment of "the age of the earth, a world wide flood, dinosaurs, pre-human fossils, dating methods, DNA, radioisotopes, and geological evidence" bespeaks a plainly religious agenda, as these are topics repeatedly singled out by proponents of creationism and "intelligent design" as reflecting areas on which evolutionary theory is flawed.

Twenty-three of the 24 videos listed on the original syllabus are one-sided presentations, produced by creation-science ministries and advocating a pro-creationism perspective, without any critical treatment of the arguments or other rebuttal. These videos are not ordinarily regarded as suitable material for the public schools because of their poor scientific quality as well as their religious advocacy. The twenty-fourth video, The Fire Below Us, pertains to volcanic activity rather than evolution and can scarcely bear the weight of holding up the "pro-evolution perspective".

The video selections — including Unlocking the Mystery of Life — also advocate the view that scientific practice should be changed and methodological naturalism should be abandoned in order to accommodate reference to the supernatural.

Similarly, the original syllabus devoted two days each to the "Laws of Thermodynamics" and "Fossil Records and Dating Methods". These are areas of scientific inquiry that proponents of creation science have traditionally attacked, with the scientific community regarding the attacks as lacking any scientific merit.

On the original syllabus, two of the five prospective speakers ([Ross] Anderson and [Joe] Francis) are identifiable proponents of creation science; a third, "David Kopich," is probably meant to refer to a local proponent of creation science named David Coppedge. Of the two prospective speakers on the original syllabus who were supposed to present the case for evolution, one is a local parent [Kenneth Hurst, the lead plaintiff] who opposed the class. The other is the Nobel laureate Francis Crick (misspelled "Krich"), who died in 2004.

The revised syllabus appears to have been revised to de-emphasize creation science in favor of "intelligent design", presumably in the hope that the course would better be able to survive constitutional scrutiny. The revision is thus a microcosm of the national debate, in which "intelligent design" emerged in the wake of Edwards v Aguillard as a form of creationism intended to avoid the Supreme Court's decision declaring the teaching of creation science in schools to be unconstitutional.

"Intelligent design" was recently recognized in Kitzmiller v Dover as unconstitutional for the same reasons as creation science was in Edwards. Although the erroneous scientific claims distinctive of creation science, such as those involving the age of the earth and thermodynamics, are no longer explicitly mentioned in the revised syllabus, "intelligent design", as the progeny of creation science, retains many of the same erroneous scientific flaws. All but one of the videos listed on the revised syllabus are the products of the "intelligent design" movement. Those videos, like the creation-science ones, are not ordinarily regarded as suitable material for the public schools.

Both the original and revised syllabi include numerous videos purporting to address the "evidence against evolution," but not a single video on either list addresses the gaps/problems with creationism or "intelligent design". Because creation science and "intelligent design" are religious rather than scientific viewpoints, advocating the tenets of these viewpoints — as opposed to addressing them in an appropriate context and in an objective manner — amounts to religious advocacy that cannot have a valid secular purpose.

Misrepresentation of the standing of evolution

Third, the course materials present a distorted view of the scientific standing of evolution. Throughout those materials, evolution is presented as a "worldview" or "philosophy". In the anti-evolution movement, these terms are often used synonymously with "religion", in order to suggest that evolution is accepted only on faith, thus converting evolution from a scientific theory (which has a particular meaning and special status in the scientific community) to a belief system (which does not).

In that regard, the very first sentence of the course description reads, "This class ... will discuss the scientific, biological, and Biblical aspects that suggest why Darwin's philosophy is not rock solid" (emphasis added).

Topics in the original syllabus include "Is Evolution a science or a philosophy?," "Is Evolution based on a religion?," and "Is evolution based on philosophy?" Although those questions are not explicitly answered in the syllabus, the fact that these questions are raised repeatedly in a course entitled "Philosophy of Intelligent Design" strongly implies that the instructor intends to teach or suggest that evolution is based on a "philosophy". The videos on the syllabi, such as "War of the Worldviews," further support that conclusion.

In the revised syllabus, although one topic is "How does the Philosophy of Intelligent Design differ from the Theory of Evolution?" (a formulation that might suggest evolution is no longer going to be presented as based on "philosophy"), the very next topic on that syllabus demonstrates otherwise by referring to "this debate concerning philosophies" — that is, evolution and "intelligent design".

Similarly, the revised syllabus states that "Equal and balanced instructions will be given on all philosophies". Because the only concepts taught are a religious view and evolution, this statement has the effect of labeling both concepts as "philosophies." Neither the original nor the revised syllabus calls for informing the students that the scientific community overwhelmingly accepts evolution.

Inaccurate and irresponsible treatment of evolution

Fourth, and related to the third consideration, is the fact that the course materials do not treat evolution in ways that are either scientifically accurate or pedagogically responsible. A genuine comparative treatment of cultural ideas concerning the origin and history of life would not necessarily have to discuss scientific ideas at all. It would be sufficient, for example, to describe the origin myths of a number of different cultures, to compare and contrast them, and to discuss the role that the origin myths play with respect to the rest of their cultures. But if scientific ideas like evolution are to be discussed in such a course, they should be discussed in a scientifically accurate and pedagogically responsible way. That is not the case with the course at issue here.

As noted, the original syllabus devoted two days to "Laws of Thermodynamics", which is a topic from physics. It is primarily proponents of creation science, and not physicists or other scientists, who regard that topic as relevant to the scientific study of evolution, for creationists incorrectly maintain that the Second Law of Thermodynamics renders evolution impossible.

The revised syllabus describes evolution as a view "on the origin of life". In the sense most common in modern biology, "evolution" denotes descent with modification — the scientific theory that living things have descended, with modification, from common ancestors. The origin of life is a separate question and a separate area of research.

Additionally, there is reason to doubt that the course presents evolution in a way appropriate to the students' ages and level of preparation. In the original syllabus, no scientifically credible and pedagogically appropriate instructional materials about evolution are listed. Apparently Mrs Lemburg was content to have the students learn about evolution almost entirely from creationist sources. Since evolution is typically presented in California only in high-school biology, it is likely that the students in this course would have had, at most, one course in which they were formally exposed to evolution; and some of the students may not have had even that. They therefore would not have the prerequisite knowledge to enable them to evaluate critically the scientific claims contained in the creationist sources.

In the revised syllabus, non-creationist instructional material about evolution was added: the PBS series Evolution, the "Understanding Evolution" website, and Evolution vs Creationism. As a consultant to the first two and the author of the third, I can certainly vouch for their scientific credibility. However, none of these materials was intended to provide a first exposure to evolution. The Evolution series was intended for a general adult audience, and (like any science documentary) was not intended to provide a complete education to its viewers. The parts of the Understanding Evolution website to which the revised syllabus refers are aimed at teachers who are striving to improve their ability to teach evolution effectively. They are not directed, aimed at, or geared to students. While there is a section of the website that provides a basic introduction to evolution, it is not mentioned in the syllabus, and it would not in any case be appropriate as the students' primary source of information about evolution. Evolution vs Creationism is suitable for advanced high-school students and for college students, but certainly not for students who have not yet even taken a biology course at the high-school level. And like the Understanding Evolution website, the book provides only the most rudimentary introduction to the science of evolution; it is no substitute for a real biology class with a competent teacher using a mainstream textbook.

If there were genuine scientific evidence against evolution — that is, if scientists had scientific debates over whether evolution actually occurred — there might be a secular pedagogical reason for teaching students "the controversy." The scientific community, however, overwhelmingly views evolution (the inference of common descent of living things) as a solidly supported scientific view. (The National Association of Biology Teachers writes, "Modern biologists constantly study, ponder and deliberate the patterns, mechanisms and pace of evolution, but they do not debate evolution's occurrence." Similarly, the National Science Teachers Association has stated, "There is no longer a debate among scientists over whether evolution has taken place," and specifically recommends that "[p]olicy-makers and administrators should not mandate policies requiring the teaching of creation science or related concepts such as 'intelligent design', 'abrupt appearance', and 'arguments against evolution'."). Indeed, the consensus of the scientific community is that "[t]he contemporary theory of biological evolution is one of the most robust products of scientific inquiry" (American Association for the Advancement of Science, AAAS Board Resolution on Intelligent Design Theory, 2002; the AAAS is the largest general scientific society in the world).

Conclusion

Because there is no scientific "evidence against evolution" and there is no pedagogical value in teaching "evidence against evolution," yet there are conspicuous religious motivations for promoting this practice, it is difficult to avoid the conclusion that the underlying purpose and the intended effect of efforts to require the teaching of "the evidence against evolution," such as those in the course at issue here, are to protect or advance a particular set of religious beliefs.

Presenting evolution in a philosophy class as a philosophy or belief system on a par with the religious view of creationism misrepresents the nature of evolution. It confuses students about what evolutionary theory is, interfering with their education when they are presented with the concept of evolution in their science classes. There can be no valid secular purpose for misleading students about the nature of evolutionary theory in a public-school philosophy class any more than there can be in a public-school science class.

Any citizen, of course, has the right to advocate a religious position, including advocating theism over materialism. But that does not translate into the right to engage in such religious advocacy in the public-school classroom. Mrs Lemburg's "Philosophy of Design" class is just such advocacy. It therefore suffers from the same defect as the teaching of creation science in Edwards and McLean, and the inclusion of intelligent design in the curriculum in Kitzmiller.

[For the sake of readability, headings were added, paragraph numbers and internal references were removed, and footnotes were incorporated into the text; a few corrections and amplifications were inserted in square brackets. For the entire declaration as submitted, visit http://www2.ncseweb.org/hurst/Scott_expert_witness_declaration-20060110.pdf.]

About the Author(s): 
Eugenie C Scott
NCSE
PO Box 9477
Berkeley CA 94709-0477
scott@ncseweb.org

Species, Kinds, and Evolution

Reports of the National Center for Science Education
Title: 
Species, Kinds, and Evolution
Author(s): 
John Wilkins
University of Queensland
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
36–45
This version might differ slightly from the print publication.
Introduction

Creationists oppose the idea that species can evolve indefinitely and charge evolutionary biologists with failing to define their terms properly. In this article I want to trace briefly the history of the idea of species and show that it is in fact a virtue of biology that it tries to make its terms follow the evidence rather than to define them all up front. The idea that species were universally thought to be fixed prior to Darwin is simply wrong — many creationist thinkers of the classical period through to the 19th century thought that species could change. The issue of evolution was, in fact, impossible to suggest until the claim was made that species were fixed, and as soon as it was suggested, so too was evolution. There has been a longstanding vagueness about living "kinds" that goes back to the classical era and that follows from good observation. What is more, nothing in the biblical or theological traditions requires that species are fixed, only that kinds exist, which neither evolutionists nor traditional creationists ever denied.

Because the number of species "concepts" in the literature is high, I have also tried to put them into context and list them for easy reference (see this page). That way, when a "concept" is referred to in a text, it can be compared to other candidate conceptions. It is clear to me, at any rate, that there are many conceptions of species, and that biologists use the one that best suits the organisms they study. I think of this as a "conceptual delicatessen" — when scientists need a species concept to suit the organisms being studied, they will typically assemble a custom "club sandwich" from previous ideas. This is not bad practice — if science is about learning and using words to express that learning, then we should expect that they would do this, and in fact they should.

To understand the concept of species, we must understand how the notion developed in the history of biological research. One point that must always be borne in mind: people did not suddenly become smart upon the publication of On the Origin of Species, nor were they bad observers before that date. And keep in mind a related point: religious commitment had little to do with the sorts of conclusions natural historians and biologists reached before Darwin, and it seems that in science, it still does not now.

The evolution of the species concept
Then God said, Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds. And it was so. The land produced vegetation: plants bearing seed according to their kinds and trees bearing fruit with seed in it according to their kinds. And God saw that it was good. …

And God said, Let the water teem with living creatures, and let birds fly above the earth across the expanse of the sky. So God created the great creatures of the sea and every living and moving thing with which the water teems, according to their kinds, and every winged bird according to its kind. And God saw that it was good. …

And God said, Let the land produce living creatures according to their kinds: livestock, creatures that move along the ground, and wild animals, each according to its kind. And it was so. God made the wild animals according to their kinds, the livestock according to their kinds, and all the creatures that move along the ground according to their kinds. And God saw that it was good.

Genesis 1, verses 11–2, 20–1, 24–5, New International Version
So long as people have been farming plants and raising livestock, they have been aware that one organism gives birth to another very like it. That is, they have known that living things come in kinds. This is not confined to the Bible, of course. Aristotle knew it. So did Theophrastus, his student, sometimes called the father of botany. It is not, as they say, rocket surgery.

So given the relatively short time scale of human observation, it followed that people would tend to think that species, living kinds, were stable; and they did. But they did not think species were unable to change for a very long time, not until John Ray, a brilliant English 17th-century botanist who compiled the first complete flora (of Cambridgeshire, and then of England), wrote in an influential work:
After long and considerable investigation, no surer criterion for determining species has occurred to me than the distinguishing features that perpetuate themselves in propagation from seed. Thus, no matter what variations occur in the individuals or the species, if they spring from the seed of one and the same plant, they are accidental variations and not such as to distinguish a species … Animals likewise that differ specifically preserve their distinct species permanently; one species never springs from the seed of another nor vice versa.
This was the first recorded biological definition of "species", although the logical term had been used in biological contexts for a long time prior to that. But his was not the traditional view. Following a suggestion of Aristotle that new species were formed by hybridization at water holes in Africa, St Augustine, among others (including one of the translators of the King James Bible), happily accepted that new species could be formed out of old ones. Linnaeus himself, who is sometimes regarded as the originator of species fixism, observed hybridization between two plant species in his own garden, and late in life revised his view that species were as the "Infinite Being" had first created them. Certainly there was no tradition in Christian theological circles that species had to be unchanging before then.

During the Middle Ages, little natural history — or biology as we would now call it — was being done. But there was an exception: the Holy Roman Emperor Frederick II of Hohenstaufen (1194–1250) was a keen falconer, and wrote, literally, the book on it, finding that Aristotle was sometimes a bit too credulous, and worse that he failed to discuss hawks, falcons, and hunting birds. Frederick had the resources and the time to do a proper study, and he found that bird species were not simple things at all. He settled on interbreeding as a standard. Albert the Great, who had access both to Frederick's falconers and writings, followed this idea. But both still took seriously enough the old idea of spontaneous generation of species from other species to investigate it. Frederick sent envoys to Sweden looking for evidence for or against the idea that the barnacle goose arose out of worms (which is how it got its name). He found no evidence and concluded that the idea was based on ignorance. Albert did breeding experiments and managed to show that the geese laid eggs in the usual manner.

So we should first of all abandon the idea that people before Darwin thought that species were fixed, necessarily. Some did; many did not. Moreover, almost as soon as the idea of species-fixism caught on, it was challenged. Linnaeus made the idea popular in his Systema Naturae, the first edition of which was in 1735. In 1745, physicist Pierre Maupertuis argued in his Physical Venus that species did evolve, that they did so through a crude version of natural selection, and that inherited characteristics were passed on in a 3:1 ratio through both mother and father. While this did not influence many people at the time, it indicates that fixism was not universal among scientists even when it was still a new idea.

Why is it that we tend to think pre-Darwinians were all fixists? In part this is because Darwin has been used as a turning point in modern biology, which of course he was, and so some, the leading evolutionist Ernst Mayr among them, have tried to make him the ultimate source of all that is correct in modern biology. Furthermore, we think that religious belief before Darwin must have forced people to be fixists. But many quite orthodox Christians held to transmutation of species, and in some cases where this was denied, such as by the great anatomist Baron Cuvier, it was not for religious reasons but from a lack of evidence (although Cuvier managed to present the evidence that florae and fauna were not constant through time, even in Europe).

It is also not true that belief in creation as such forced a species-fixist position. Apart from deism, which perceived God as a creator who effectively left the world to run by the laws he created, many Christians held that the work of creation was still under way. And Christians who were natural historians, whether botanists or zoologists, often described species fairly well.

There is another myth — that before Darwin naturalists thought that species were defined by their morphology or their "essence". But morphology was used by taxonomists simply as a way to identify species, not as the cause of them, and even Linnaeus knew that his "Natural System", as it came to be called, was a useful convention, not a natural system at all. Taxonomists argued about how to define species, but in nearly all cases this was about how many and what kinds of characters were reliable. In the early 19th century, there was no "species problem", but only a "species question", which a minor geologist by the name of Charles Lyell called "that mystery of mysteries" — why were there species? It was not a question he, an orthodox Christian, thought could be answered from Scripture. Neither did his eventual disciple Darwin think that.

Darwin's view of species has likewise been misunderstood, in part because he did not really consider the definition of a species to be the primary question. Like many professional taxonomists (Darwin wrote the first and still one of the best descriptions of barnacles), he found the constant squabbling about whether this variety or that was a separate species or the same to be a nuisance to doing the work. He cited with wry amusement one taxonomist, Phillips, who declared "at last I have found out the only true definition — ‘any form which has ever had a specific name'!" And there was, in 1842, a set of standards from which all modern taxonomic rules derive — Darwin was a committee member — which formally instituted the rule of Linnaeus that species had to have a binomial (a genus and species name), and that only professionals could name species (to stop bird-watching enthusiasts naming every different plumage as a species). In the Origin, he wrote:
… it will be seen that I look at the term species as one arbitrarily given, for the sake of convenience, to a set of individuals closely resembling each other, and that it does not essentially differ from the term variety, which is given to less distinct and more fluctuating forms. The term variety, again, in comparison with mere individual differences, is also applied arbitrarily, for convenience's sake.
On the basis of this and other comments, he seemed to be saying that a species was not a real thing, but that it was just what we called something for convenience. But in his works overall, he treats species as real things, mostly (but not always) isolated by infertility, with different ecological adaptations. His point was, and it remains a sticking point today, that the difference between a species and a variety within a species was vague. This, of course, is due to the fact that species, like sand dunes, rivers and clouds, have no hard and sharp boundaries between them because of evolution.

About the time evolution had been universally accepted by naturalists (now called biologists), but before the new Darwinism of the synthesis of genetics and evolution had been settled, one EB Poulton wrote a paper in 1903 entitled "What is a species?" in which he addressed what now became the species "problem". This set the agenda for the next century. From being the useful identification of kinds that might vary, in the late Middle Ages and after, through to being a problem of who got to name species and how they were to be differentiated, now species were the "units" of evolution, and of biology in general. And a veritable explosion of attempts to define species followed. By the end of the 20th century, there had been some 22 distinct concepts identified by RL Mayden, and depending on how one divides them, some few others have been added. By my count, there are around 26 concepts (see sidebar, p 42–3).

Well, not exactly concepts. There is only one concept, which we label by the word "species". There are 26 or so conceptions, or definitions, which we define in other ways. This slightly picky philosophical point matters. We are arguing over the best way to define a concept. This depends on scientific data, theory, and other factors (some of them political, within the scientific community). We might deny that the concept even has a useful definition, or we might think that we have been misled by the use of a single word and seek a number of different concepts that serve the purposes of science and knowledge. I mention this because one of the oft-repeated claims made by anti-evolutionists is that if we cannot define our terms, we cannot show that species evolve. This canard goes back to Louis Agassiz, the famous geologist and paleontologist, who single-handedly introduced America to biology. Agassiz wrote:
[I]f species do not exist at all, as the supporters of the transmutation theory maintain, how can they vary? And if individuals alone exist, how can differences which may be observed among them prove the variability of species?
Darwin rightly snorted to Agassiz's one-time student Asa Gray:
I am surprised that Agassiz did not succeed in writing something better. How absurd that logical quibble — "if species do not exist how can they vary?" As if anyone doubted their temporary existence.
Creationists will often claim that they are not interested in the species level, though. Initially, creationism did require fixity of species. In the 1920s, when George McCready Price equated "species" to the biblical "kinds", he was forced, to allow for the Ark to carry "every kind", to raise the bar higher. Even this was not original. In the late 18th century, Buffon, Cuvier's predecessor, had suggested that there was a "first stock" from which all members of a kind had evolved, so that all cats evolved from an original animal, modified by geography and climate, for instance. So creationists themselves have a "vagueness problem" no less than evolutionary biology does. Life is vague. Certainly the creationist "kind", or "baramin", as they mangle the Hebrew for "created kind", is extremely elastic. Given that elasticity, the motivation for the inference that was made naturally during the 17th and 18th centuries that species do not evolve is undercut. If kinds are not exact in reproduction, why think that the Genesis account is enough to prohibit evolution? The answer is, of course, that biblical literalism is not the primary motivation here for opposition to evolution.

The species problem

Reproductive isolation conceptions
It begins in 1935, when a young fruit fly geneticist named Theodosius Dobzhansky published a paper "A critique of the species concept in biology" in a philosophy journal. Not that there had not been developments after Darwin. Various people had suggested that species were "pure gene lines" or "wild-types" that did not vary much. Mendelian genetics caused a lot of debate about species. Dobzhansky claimed that a species was:
… a group of individuals fully fertile inter se, but barred from interbreeding with other similar groups by its physiological properties (producing either incompatibility of parents, or sterility of the hybrid, or both).
This was the original genetic version of reproductive isolation concepts (Buffon had proposed interbreeding as a test a century and a half earlier, which Darwin rejected). Unfortunately, a version framed by Ernst Mayr got called the "biological" species concept, in contrast to what were seen as "nonbiological" concepts that relied largely on form and based in museum taxonomy, which were called "morphological" concepts by Mayr. But I think it is better to call these Reproductive Isolation Species Concepts (RISC) than "biological" ones, for any decent species conception is biological. Mayr's version changed over the years, but the one taught to most undergraduate biology students is the original:
A species consists of a group of populations which replace each other geographically or ecologically and of which the neighboring ones intergrade or interbreed wherever they are in contact or which are potentially capable of doing so (with one or more of the populations) in those cases where contact is prevented by geographical or ecological barriers.
Or shorter:
Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.
Much of the focus on species after this centered on Reproductive Isolating Mechanisms, or RIMs for short. Mayr's view was that species are formed when part of the species is geographically isolated from the main range and evolves in its own way such that when it gets back in contact, RIMs have evolved, as it were, by accident, and the two no longer interbreed successfully. Selection against hybrids, which are, so to speak, neither fish nor fowl in ecological adaptations, then strengthens the isolation (a process called "re-inforcing selection"). Mayr's version of the origin of species, published in 1942 and reiterated for the next 60 years (Mayr survived to 100, outliving many of his adversaries, and thus getting the last word), is called the allopatric theory of speciation. Allopatry means that two populations, or species, or groups, of organisms live in different areas (allo- = other, patria = homeland). The alternative kind of speciation, which is in effect Darwin's view, is called sympatric (sym- = together) speciation, and it is highly contentious among specialists, with some thinking that it occurs, particularly among fruitflies and lake-bound fishes, where it has been studied, and others thinking that it does not, and the debate goes on. It requires that RIMs evolve in place, so to speak, and the naysayers think this is unlikely to occur. If sympatric speciation does occur, then there can only be one reason — natural selection. Recent theoretical work shows that it is possible if the conditions are right. What we do not yet know for sure is how often the conditions are right.

There is another uncontested class of speciation processes — usually involving hybridization, that old idea of Aristotle. In plants particularly, but also in animals, fungi, bacteria, and so on, sometimes entire genetic complements can double, triple or more, resulting in a condition known as polyploidy. When this happens, sometimes the chromosomes and genes do not line up due to differing genetic structures of the parents, but an extra doubling of the genome, followed by a cell division, can give the cell a paired set of chromosomes, allowing it effectively to found a new species in one or a few generations. When two species interbreed, this allows the resulting organism to have a matched set of chromosomes. It has been estimated that nearly all ferns, for example, have a case of polyploidy in their ancestry, and as many as 7% of actual fern species are formed this way. It has also been seen in flowering plants, corals, grasshoppers, other insects, and reptiles. It is even hypothesized that the entire mammalian branch of the evolutionary tree was started with this kind of event. So in a sense, Linnaeus and Aristotle were right … sort of. Even Mendel thought this might be the reason why new species evolve, which informed his research into hybrid forms, although he studied hybridization within, not between, species.

Evolutionary conceptions
So the RISC conceptions have a lot of leeway for interpretation. But they are not the only conceptions on the board. One kind of conception goes by the name evolutionary species concepts, which is also a misnomer (because all species have evolved). On this view, it does not much matter if two possible species under consideration are reproductively isolated. Even if there is gene flow between them on a regular basis, what counts is whether or not they remain evolutionarily distinct. Dobzhansky's definition has a hint of this, but the original formulation is due to a paleontologist, George Gaylord Simpson. Simpson defined it this way in 1961, although there is an earlier and more technical definition from ten years before:
An evolutionary species is a lineage (an ancestral–descendant sequence of populations) evolving separately from others and with its own unitary evolutionary role and tendencies.
What counts here is that no matter what happens in terms of gene exchange, the populations remain distinct, and have their own forms, adaptations, and fate. The term "lineage" used here is particularly important, as it focused biologists' thinking more in evolutionary terms, and gave rise to yet another class of conceptions — phylogenetic species concepts.

Evolutionary conceptions have been expanded since Simpson to include asexual organisms (which do not, strictly speaking, form populations, since that term involves interbreeding). The important point is that there is a single lineage over time. In contrast, the RISC conceptions involve a single time "horizon", which means that a species is something that at a particular time and place is not interbreeding with other populations, and they also, necessarily, exclude asexual organisms.

Phylogenetic conceptions
There is a group of species conceptions that go under the shared name of phylogenetic species concepts. A phylogeny is, of course, an evolutionary history, and the initial proposal for a phylogenetic conception came from Willi Hennig, an East German entomologist who nevertheless managed to influence a great many biologists during the height of the Cold War. Hennig's methodology and philosophy of classification is known today as "cladistics".

Hennig did not set out to come up with a new species concept. He pretty much assumed something like an amalgam of Mayr's and Simpson's definitions. The difference was that he focused on the lineage element, and combined it with a clear and formal account of making groups logically. In his book Phylogenetic Systematics, translated into English in 1966, he included a diagram about speciation (redrawn above as Figure 1), and when to name a new species.

There are several lineages in this diagram. Ignoring the technical terminology (Hennig was a great one for coining classical names), you can see that each individual organism is part of a genealogical lineage. These, when grouped together, form a species lineage. Clearly what makes a species lineage is the fact that the overall tangled net of genealogical lineages has not yet divided (as in the right-hand diagram marked "phylogenetic relationships"). When it has, says Hennig, the old species is extinguished and two new ones come into being (as in the separate circles at the top).

This provision caused a lot of anxiety. It seemed to be saying that a species has to go extinct when new ones come into being, but of course a new species can evolve without modifying the old one much, if at all. Hennig's convention, as it is known, was more a point about naming species than a definition of their biological nature. When a new species arises, the old name refers to only a part of its descendants and for Hennig that meant it was no longer a "natural" group being named. It is rather like calling rock music "blues" because it is a descendant of blues. What Hennig said would mean that what is still "blues" has to get a new name so that musicologists can talk without ambiguity (so it might get called "traditional blues").

Phylogenetic species conceptions come in three broad flavors. One is the "pure" Hennigian conception described above. But Hennig's methodology also relied on dividing organisms by shared features, which is a diagnostic question. So another phylogenetic conception, which I call the autapomorphic conception (after one of Hennig's technical terms that means "derived forms"), defines a species as the final node on a phylogenetic tree, which is based on comparison of many features. If the analysis does not produce any smaller group, then the organisms in this group constitute a species. This has a side effect of increasing the number of species over the older RISC conception — by as many as five times — and for this reason it is not accepted by many taxonomists. On the other hand, if a species really is just the as-yet-undivided tangled net of genealogical relations, this is what we have to deal with. The autapomorphic conception tends to leave historical issues about whether or not the phylogenetic tree is a good historical representation to one side. The "species" here is diagnostic.

The other conception I call the phylogenetic taxon conception. On this view, a species is just another kind of taxon in a phylogenetic tree — one that happens to be monophyletic and undivided. Monophyly in this case simply means that no descendent of the original species is excluded, so that if a single species did divide into two, it would have been a species before, but is now two species, which is pretty obvious. However, this view allows the old name to be "kept" by one of the descendants.

Phylogenetic conceptions are in a way parasitic on biological conceptions like RISC. In order to know that two organisms are in the same species, one has to eliminate subspecific features such as, for example, different plumages or immune system molecules or genes. Otherwise one can divide the organisms up right down to individuals with novel mutations or slight variations. There are those who do this, too, who intend to eliminate "species" from the working vocabulary of biologists and replace it with "evolutionary group" or "least inclusive taxon"; we may refer to them collectively as "species eliminativists".

Ecological conceptions
In the 1920s, a Swedish botanist named Göte Turesson proposed that there were different kinds of "species", one of which was a response to the local ecology. Though not Mendelian, as Turesson appeared to think the environment changed genes directly, his ecospecies concept has been revived from time to time. Various authors, including Mayr, have suggested that what makes a species is occupation of an ecological "niche", and in 1976 American botanist Leigh Van Valen suggested that a species was a lineage "which occupied an adaptive zone" differently to other species. Van Valen's "proposal" (he did not call it a definition) combined both Mayr's RICS account and Simpson's evolutionary account, for the "adaptive zone" idea is Simpson's as well.

Van Valen's example case was the American white oak complex, Quercus, which will interbreed fairly freely, and yet remains stable phenotypically. This is due, he said, to adaptation for particular ecological needs. Similar cases have been found elsewhere; for example, Australian eucalypts interbreed with more distant relatives, but are often infertile with closer ones.

The idea that underpins this conception is the famous "adaptive landscape". A species, no matter what the gene flow between populations of other species, occupies a "peak" in that landscape (see, for example, the view espoused by Richard Dawkins in his Climbing Mount Improbable [New York: WW Norton, 1996]) where the metaphor of an adaptive landscape implicitly assumes this. Ecospecies are formed when the adaptive landscape "fractures", to use a term from philosopher Kim Sterelny. Recent work on speciation suggests that this is a factor in most cases, although it has a different role in allopatric speciation than in sympatric or polyploid speciation.

A grab bag of conceptions
As with any taxonomy, there are a few things that do not fit neatly into this scheme. Many of the current conceptions mix and match aspects of these conceptions, so a particular description might be characterized as, say, an isolationist, evolutionary, genetic account. But there are also species conceptions that make positive proposals, for example, for asexual species. At one time it was open to doubt that such things existed, or were rare, but apart from bacterial species (which sometimes do not have "sexes" but can exchange genes in various conditions), there are an increasingly known number of "parthenogenetic" species (in animals — in plants they are called "apomictics") that do not need to fertilize their ova or seed. Organisms that are descended from sexual organisms are sometimes asexual, such as the famous whiptail lizards of the southern USA and northern Mexico (genus Cnemidophora). In many cases these are formed by hybridization between closely related species, in animals and plants. Viruses also form "species" called "quasispecies", usually without crossing over their genetic material.

Another species conception is sometimes called "conventionalism", or less accurately but more commonly "species nominalism". This view is very popular among those whose ideas about evolution derive from the work of geneticist JBS Haldane early in the 20th century. It is basically the claim that species are just names, chosen for convenience, so that specialists can talk to each other. However, if species are just convenient fictions, how do specialists know that their terms refer to the same things?

And finally let us consider the problems of identifying species in fossils. Not all information about an organism is recorded in a fossil. We have data about hard parts, and, more rarely, skin or feather impressions, but we are not given their genetics, behaviors, colors, ranges, or mating preferences. And these are often the markers of being a RISC species, or are used to diagnose phylogenetic species. "Paleospecies", as they are sometimes called, may be less arbitrary than conventionalist species, but they do not necessarily map onto "biological" species.

Consider the debate in human evolution over whether Homo sapiens left Africa entire, as it were, or whether a prior paleospecies, Homo erectus, interbred with H sapiens afterwards. Recent work by Alan Templeton suggests there have been three major migrations out of Africa, each of which has left a genetic mark on the modern population. So, are H erectus and H sapiens one species, or two? We may be able to work that out through the sort of work Templeton is doing, but we equally may not.

Knowing species
Now the "biological", the evolutionary and the phylogenetic conceptions have an operational problem for biologists — except in very rare circumstances, it is almost impossible to give the criteria of the definitions for identifying and demarking species. There have been cases where two forms have been identified as the same species because they were observed mating, but there just are not the resources or the time to do experiments of assortative mating to tell in every case. In fact, many "biological" and evolutionary species, such as tigers and lions, which have been isolated for millions of years, can interbreed in artificial conditions, and their progeny are fertile, so mating tests might not help anyway. Back in the 18th century, Buffon established that some species could occasionally interbreed (which is why he thought that there was a first stock for groups of animals). So the definitions, or conceptions as I prefer, are not much help. And so far as evolutionary conceptions go, we simply have no direct access to the evidence we need in the case of extinct and even extant species. It might be true that species have distinct fates, but often we do not know.

It is important to separate the issues of what species are from the issues of how species are known or identified, because while evolutionary biology and genetics indicate some of the processes by which species evolve, the tests we use to find out whether two organisms are the same species or not may in fact be quite incidental to the causes of their being species. Many tests are used, mostly genetic and molecular tests these days. A recent proposal called DNA barcoding uses a particular gene on the cellular organelles known as mitochondria quickly to identify species for conservation and other purposes, but nobody thinks that the gene, COX1, causes speciation. In fact in cases where the "speciation genes" have been studied, they are nuclear genes, not mitochondrial genes (and anyway it is unlikely that the same genes cause speciation in all groups). When creationists attack evolutionary biology for not being able to define the term "species", they are confusing the identification and diagnosis of species and the meaning of the term "species". Occasionally, some scientists do the same thing.

Suppose we take a nonbiological example — "mountain". If we cannot give a universal definition of that term, it does not mean there are no mountains, or even that we cannot tell whether we are looking at one. And the geological theory of plate tectonics explains why there are mountains even when the term is not definable. Definitions are for philosophy, but science can do without them if it needs to. Species are the phenomena of biology that the theory explains, not a priori concepts that have to be clarified exactly. It may be that, as some propose, we ought to replace the term with a range of other terms, such as "evolutionary group", "least inclusive taxonomic unit", and so on. Some "species" will be both evolutionary groups and least inclusive taxa. Some may not. The jury is still out as to the worth of these ideas.

Evolutionary biologist Massimo Pigliucci and philosopher Jonathan Kaplan have proposed that the term "species" is in fact what philosophers call a "family resemblance predicate". This is when being an instance of a general kind referred to by a word (the classic philosophical example is "game") has many criteria, and as long as most of them are met by a particular instance, it is a part of the kind. If evolution proceeds as we should expect from modern theory, then this plethora and confusion of species concepts is easily explained — evolution is a gradual process at genetic and behavioral scales (but it can be abrupt at geological and ecological scales), and so we will see species in all kinds of stages of speciation, extinction, interbreeding compatibility, and so on. On a creationist account, of course, no such explanation is forthcoming. If "kinds" are fixed, we should see only the expression of created variety (and of course that variety could not have possibly passed through the Ark, but let us assume that creationism is separate from Flood literalism), and that should be definite and limited. Instead we see species in groups of varying and ill-defined variety. It is a lot of weight for a simple word — "kind" — to bear. Science does not need it — so long as the ways words are used by each speciality will serve to describe what is observed.

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About the Author(s): 
John Wilkins
Biohumanities Program
School of History, Philosophy, Religion and Classics
University of Queensland
Brisbane, Australia 4072
john.s.wilkins@gmail.com

John Wilkins is a postdoctoral fellow in the Biohumanities Project at the University of Queensland, Australia. His PhD topic was on species concepts, and he is working in the field of philosophy of taxonomy.

Species Concepts in Modern Literature

Please note: This text is part of Species, Kinds, and Evolution, by John Wilkins, Reports of NCSE 26 (4), 2006.

Summary of 26 species concepts

There are numerous species "concepts" at the research and practical level in the scientific literature. Mayden's (1997) list of 22 distinct species concepts along with synonyms is a useful starting point for a review. I have added authors where I can locate them in addition to Mayden's references, and I have tried to give the concepts names, such as biospecies for "biological species", and so on (following George 1956), except where nothing natural suggests itself. There have also been several additional concepts since Mayden's review, so I have added the views of Pleijel (1999) and Wu (2001a, 2001b), and several newer revisions presented in Wheeler and Meier (2000). I also add some "partial" species concepts — the compilospecies concept and the nothospecies concept. In addition to Hennig's conception (1950, 1966), I distinguish between two phylospecies concepts that go by various names, mostly the names of the authors presenting at the time (as in Wheeler and Meier 2000). To remedy this terminological inflation, I have christened them the autapomorphic species conception and the phylogenetic taxon species concept. Asterisks identify the "basic" conceptions, from which the others are formed.

1. Agamospecies*
Asexual lineages, uniparental organisms (parthenogens and apomicts), that cluster together in terms of their genome. May be secondarily uniparental from biparental ancestors. Quasispecies are asexual viruses or organisms that cluster about a "wild-type" due to selection. See Cain (1954), Eigen (1993, for quasispecies). Synonyms: Microspecies, paraspecies, pseudospecies, semispecies, quasispecies, genomospecies (Euzéby 2006, for prokaryotes).

2. Autapomorphic species
A phylospecies conception. A geographically constrained group of individuals with some unique apomorphous characters, the unit of evolutionary significance (Rosen 1979); simply the smallest detected samples of self-perpetuating organisms that have unique sets of characters (Nelson and Platnick 1981); the smallest aggregation of (sexual) populations or (asexual) lineages diagnosable by a unique combination of character traits (Wheeler and Platnick 2000). Nelson and Platnick (1981); Rosen (1979).

3. Biospecies*
Defined by John Ray, Buffon, Dobzhansky (1935); Mayr (1942). Inclusive Mendelian population of sexually reproducing organisms (Dobzhansky 1935, 1937, 1970); interbreeding natural population isolated from other such groups (Mayr 1942, 1963, 1970; Mayr and Ashlock 1991). Depends upon endogenous reproductive isolating mechanisms (RIMs). Synonyms: Syngen, speciationist species concept.

4. Cladospecies
Set of organisms between speciation events or between speciation event and extinction (Ridley 1989), a segment of a phylogenetic lineage between nodes. Upon speciation the ancestral species is extinguished and two new species are named. See Hennig (1950; 1966); Kornet (1993). Synonyms: Internodal species concept, Hennigian species concept, Hennigian convention.

5. Cohesion species
Evolutionary lineages bounded by cohesion mechanisms that cause reproductive communities. See Templeton (1989).

6. Compilospecies
A species pair where one species "plunders" the genetic resources of another via introgressive interbreeding. See Harlan (1963); Aguilar and others (1999).

7. Composite Species
All organisms belonging to an internodon and its descendents until any subsequent internodon. An internodon is defined as a set of organisms whose parent–child relations are not split (have the INT relation). See Kornet and McAllister (1993).

8. Ecospecies*
A lineage (or closely related set of lineages) which occupies an adaptive zone minimally different from that of any other lineage in its range and which evolves separately from all lineages outside its range. See Simpson (1961); Sterelny (1999); Turesson (1922); Van Valen (1976). Synonyms: Ecotypes.

9. Evolutionary species*
A lineage (an ancestral–descendent sequence of populations) evolving separately from others and with its own unitary evolutionary role and tendencies. See Simpson (1961); Wiley (1978, 1981). Synonyms: Unit of evolution, evolutionary group. Related concepts: Evolutionary significant unit.

10. Evolutionary significant unit
A population (or group of populations) that (1) is substantially reproductively isolated from other conspecific population units, and (2) represents an important component in the evolutionary legacy of the species. See Waples (1991).

11. Genealogical concordance species
Population subdivisions concordantly identified by multiple independent genetic traits constitute the population units worthy of recognition as phylogenetic taxa. See Avise and Ball (1990).

12. Genic species
A species formed by the fixation of all isolating genetic traits in the common genome of the entire population. See Wu (2001a; 2001b).

13. Genetic species*
A group of organisms that may inherit characters from each other, a common gene pool, a reproductive community that forms a genetic unit. See Dobzhansky (1950); Mayr (1969); Simpson (1943). Synonyms: Gentes (singular: gens).

14. Genotypic cluster
Clusters of monotypic or polytypic biological entities, identified using morphology or genetics, forming groups that have few or no intermediates when in contact. See Mallet (1995). Synonyms: Polythetic species.

15. Hennigian species
A phylospecies conception. A tokogenetic community that arises when a stem species is dissolved into two new species and ends when it goes extinct or speciates. See Hennig (1950, 1966); Meier and Willman (1997). Synonyms: Biospecies (in part), cladospecies (in part), phylospecies (in part), internodal species.

16. Internodal species
Organisms are conspecific in virtue of their common membership of a part of a genealogical network between two permanent splitting events or a splitting event and extinction. See Kornet (1993). Synonyms: Cladospecies and Hennigian species (in part), phylospecies.

17. Least Inclusive Taxonomic Unit (LITUs)
A taxonomic group that is diagnosable in terms of its autapomorphies, but has no fixed rank or binomial. See Pleijel (1999); Pleijel and Rouse (2000).

18. Morphospecies*
Defined by Aristotle and Linnaeus, and too many others to name, but including Owen, Agassiz, and recently, Cronquist. Species are the smallest groups that are consistently and persistently distinct, and distinguishable by ordinary means. Contrary to the received view, this was never anything more than a diagnostic account of species. See Cronquist (1978). Synonyms: Classical species, Linnaean species.

19. Non-dimensional species
Species delimitation in a non-dimensional system (a system without the dimensions of space and time). See Mayr (1942, 1963). Synonyms: Folk taxonomic kinds (Atran 1990).

20. Nothospecies
Species formed from the hybridization of two distinct parental species, often by polyploidy. See Wagner (1983). Synonyms: hybrid species, reticulate species.

21. Phenospecies
A cluster of characters that statistically covary; a family resemblance concept in which possession of most characters is required for inclusion in a species, but not all. A class of organisms that share most of a set of characters. See Beckner (1959); Sokal and Sneath (1963). Synonyms: Phena (singular: phenon) (Smith 1994), operational taxonomic unit.

Phylospecies
The smallest unit appropriate for phylogenetic analysis, the smallest biological entities that are diagnosable and monophyletic, unit product of natural selection and descent. A geographically constrained group with one or more unique apomorphies (autapomorphies). There are two versions of this and they are not identical. One derives from Rosen and is what I call the autapomorphic species conception. It is primarily a concept of diagnosis and tends to be favored by the tradition known as pattern cladism. The other is what I call the phylogenetic taxon species conception, and tends to be favored by process cladists. See Cracraft (1983); Eldredge and Cracraft (1980); Nelson and Platnick (1981); Rosen (1979). Synonyms: Autapomorphic phylospecies, monophyletic phylospecies, minimal monophyletic units, monophyletic species, lineages.

22. Phylogenetic Taxon species
A phylospecies conception. A species is the smallest diagnosable cluster of individual organisms within which there is a parental pattern of ancestry and descent Cracraft (1983); Eldredge and Cracraft (1980); the least inclusive taxon recognized in a classification, into which organism are grouped because of evidence of monophyly (usually, but not restricted to, the presence of synapomorphies), that is ranked as a species because it is the smallest important lineage deemed worthy of formal recognition, where "important" refers to the action of those processes that are dominant in producing and maintaining lineages in a particular case Nixon and Wheeler (1990); Mishler and Brandon (1987).

23. Recognition species
A species is that most inclusive population of individual, biparental organisms which share a common fertilization system. See Paterson (1985). Synonyms: Specific mate recognition system (SMRS).

24. Reproductive competition species
The most extensive units in the natural economy such that reproductive competition occurs among their parts. See Ghiselin (1974). Synonyms: Hypermodern species concept.

25. Successional species
Arbitrary anagenetic stages in morphological forms, mainly in the paleontological record. See George (1956); Simpson (1961). Synonyms: Paleospecies, evolutionary species (in part), chronospecies.

26. Taxonomic species*
Specimens considered by a taxonomist to be members of a kind on the evidence or on the assumption they are as alike as their offspring of hereditary relatives within a few generations. Whatever a competent taxonomist chooses to call a species. See Blackwelder (1967), but see also Regan (1926); Strickland and others (1843). Synonyms: Cynical species concept (Kitcher 1984).

Ten (Eleven) Things Evolutionists Can Do to Improve Communication

Reports of the National Center for Science Education
Title: 
Ten (Eleven) Things Evolutionists Can Do to Improve Communication
Author(s): 
Randy Olson
Volume: 
26
Issue: 
4
Year: 
2006
Date: 
July–August
Page(s): 
23
This version might differ slightly from the print publication.
A PDF version of this article is available here.

1) Quality Control: So much of the mass communication of evolution is dull and uninspiring. For example, the AIBS-sponsored video Evolution: Why Bother? is tragically bad — nothing but talking heads and still images. Any introductory film student could have explained to them that in film and video the primary communication takes place through the images presented. When all we show are faces talking, we communicate virtually nothing. We need the simple, honest feedback gained by showing these productions to our neighbors and watching them fall asleep. Just send the sponsors a note that this is not good enough. Raise the bar. It's that simple. When evolution media looks bad, evolutionists look bad. Cost to you of this suggestion: $0.

2) Attitude: Never "rise above" one of the simple principles we learned in acting class. Whenever we condescend, we lose the sympathy of our audience. When evolutionists call ID proponents "idiots", it just makes the audience side with the people being ridiculed. It is a simple principle of mass communication. Even though Stephen Jay Gould was my hero in graduate school nearly 30 years ago, my students at USC find his style and voice to be arrogant, elitist, condescending, verbose ... the list goes on. Cost to you of this suggestion: $0.

3) Concision: It is a by-product of the information era. Get used to it. In fact, practice it. The most effective means of communication is through storytelling. The shorter, more concise, and punchier the story, the more engaged and interested the audience. Scientists need to maintain accuracy and precision, but shorter, punchier stories will not hurt anything. Observe Hollywood and advertising pitchmen: they are able to tell entire stories in very few words. Cost to you of this suggestion: $0.

4) Modernization: A recent CNN poll showed that 44% of Americans get their information on science and technology through television — more than through any other medium. So why isn't the world of science communication geared towards this, even just a little bit? There are now dozens of science writing programs around the country; why no science electronic media programs? Cost to you of this suggestion: $0.

5) Setting Priorities: Effective communication costs money — real, cold, hard dollars. Scientists sit through technical talks with bad visuals and poor sound, and seem to accept it as standard practice. On a wider scale, this is mirrored in the tiny allocation for science communication in research grants (occasionally a few dollars are allocated for outreach). Compare this with businesses making products and spending perhaps half of their budgets on marketing and advertising. Everyone needs to accept that we live in an information-glutted world, and if we do not pay sufficient attention to communicating effectively what we have to say, then we will be unheard. It is a matter of priorities. Cost to you of allocating more funds to communication: as much as you can afford, but it is time to make it hurt a little, to make up for the lack of priority on communication in the past.

6) Understanding: Intellectuals are handicapped as mass communicators. I had this line in my film, and took it out because it sounded too insulting, but it's true. Mass audiences do not follow people who think, they follow people who act. Try taking an acting class and you'll get to know about this intimately. Cost to you of this suggestion: $0.

7) Risk Taking/Innovation: Every stock investor knows you allocate at least 10% of your stock portfolio to high-risk ventures. There are no signs that formal investment in high-risk innovation of science communication has been taking place. You need to ask your science agencies what percentage of their funding is going to high-risk, wild ideas for mass communication. They may sound irresponsible, but without these ideas, you end up with homogenization. Come on, folks, we're talking about basic out-breeding dynamics here. Cost to you of this suggestion: $0.

8) Humor: This is yet another by-product of the information era. It is no coincidence that news anchors, who were stoically serious 30 years ago, today tell jokes and tease each other, or that The Daily Show on Comedy Central is the most popular form of news for kids (as well as a lot of adults); or that Michael Moore, Al Franken, and Bill Maher have become such popular news critics. Humor has become a major channel of communication. So lighten up, evolutionists. Cost to you of this suggestion: $0.

9) Unscripted Media and the Mass Audience: This goes with modernization. The mass audience has changed drastically in just the past decade. About half of the acting jobs available a decade ago in Hollywood have been lost to reality television — which is unscripted entertainment. The mass audience is bored and desperate for anything unpredictable. This is why, at our Yale University screening of Flock of Dodos, when evolutionist Richard Prum, in a moment of brilliance, yanked the microphone away from me as I droned on about the need for spontaneity, the audience erupted more than at any other moment in the entire evening. Cost to you of this suggestion: $0.

10) Sincerity: Even though Prum was a bit ungainly after grabbing the microphone, the audience didn't care. The gesture was so sincere, came from such a visceral level, showed such passion, such risk-taking, so much desire to act (rather than just pontificate as I was doing), that he stole their hearts. There is a great deal to be learned from that. Cost to you of this suggestion: $0.

11) Casting: All advocates are not created equal when it comes to communicating with the public. Suffice it to say: even if you have a Nobel prize and even if you give really great lectures, you still might not be the best person on camera. One bad twitch will set back your cause despite all your knowledge and advanced degrees. But ... pick the right person even if this is only the chair of a state curriculum writing committee— in my movie this was Steve Case, who is the most popular and instantly likable scientist I've ever seen on film — and the impact can be far greater than what you get using any Nobel laureate. And by the way, there's only one group of people who can decide for certain if your spokesperson is effective: your audience. Theirs is the only opinion that matters. Cost to you of this suggestion: potentially bruised egos and $0.

Value of better public understanding of science: priceless.

Review: Cladistics

Reports of the National Center for Science Education
Volume: 
26
Year: 
2006
Issue: 
4
Date: 
July–August
Page(s): 
45
Reviewer: 
Alan Gishlick
Gustavus Adolphus College
This version might differ slightly from the print publication.
Work under Review
Title: 
Cladistics: A Practical Primer on CD-Rom
Author(s): 
Peter Skelton and Andrew Smith
accompanying booklet by Neale Monks, 80 pages
Cambridge: Cambridge University Press, 2002.
Teaching cladistic methodology has always been a challenge, especially if you want to present an in-depth introduction to the topic as opposed to a brief overview. One of the standard sources for teaching cladistics in upper-level systematics classes was The Compleat Cladist (Wiley and others 1991). That book, however, has long been out of print, and unless you wanted to send your students to a used book dealer to find a textbook, there were few decent choices other than photocopies and primary literature.

With the publication of the Cladistics CD-ROM and booklet, there is now a good introductory resource on cladistics available for teachers. The CD-ROM is meant to be the main teaching source and can be used on its own; the booklet, by itself, can also serve as a good stand-alone text. The descriptions are clear and easily understandable in both media, with the booklet helping to elaborate the concepts presented in the CD-ROM. Used together, they constitute perhaps the best widely available resource for teaching introductory cladistics.

The booklet is meant as a companion for students using the CD-ROM to learn the basics of cladistics as well as the way phylogenies are computed. Its five chapters are well-organized, progressing logically from the very basic concepts behind cladistics to defining characters and character homology, generating cladograms, and testing the robustness of those cladograms, and finally to a practical hands-on exercise that allows the student to generate both molecular and morphological trees of several species of echinoids and to compare the results of the analyses.

The booklet has an excellent introduction to parsimony, and it goes through a series of complex topics with clarity and simplicity. It has a very clear introduction and explanation of molecular-based cladistics absent from previous texts. I do wish that there were more of a focus on morphological characters at the beginning. It contains an excellent discussion of homology and homoplasy in respect to pleisiomorphy and synapomorphy. It also offers perhaps the clearest discussion I have read for determination of homology in molecular data.

The CD-ROM is both informative and interactive. It is especially useful for teaching about molecular characters. The final section gives the student the opportunity to code characters from raw morphological and molecular data and then perform the analysis with the aid of the CD-ROM.

The chapters in the CD-ROM are interspersed with interactive exercises that test the student’s understanding of the various concepts as they are presented. I found them to be, on the whole, rather good. There were a few places where the exercises were not quite clear. Although the CD-ROM gives the student a chance to create matrices from raw morphological and molecular data, I think that there still is a lot of value in working out the transformation series the old-fashioned way, by hand. That is how to acquire a real understanding of what modern computer programs for cladistics are doing inside the “black box”. So there is room for improvement in the exercises, but otherwise I have no problem with them. Indeed, I think that more exercises, especially in the booklet, would be useful.

Perhaps the biggest problem with the CD-ROM is the narration. The text of the CD-ROM is spoken in a rather stuffy and pedantic British accent, which cannot be turned off. This conjures visions of American students sitting in their computer labs imitating the voice in horrible American British accents, saying things like “These parsimony criteria are jolly good.” I mean no offense to speakers of the Queen’s English, whose accents I generally find to be quite pleasant; however, in this case, I could have done without. I have no idea how British students may perceive the narration, but for Americans, the ability to replace the narration with a more familiar accent or at least on-screen text would be a welcome addition to the CD-ROM. Of course, such a minor point should by no means deter both students and teachers alike from acquiring this excellent introduction to a very important topic in the modern life sciences.

Overall, Cladistics is an excellent resource for learning the methods that are universal in systematics today. The booklet is an excellent learning resource useful for students in systematics classes or for people who wish to learn the methods of cladistics for themselves. The interactive CD-ROM exercises provide good hands-on activities, and the focus on molecular methods is invaluable, given their significance to current phylogenetics. Now if only there was a way to turn off the stuffy British narration ...

Reference



Wiley EO, Siegel-Causey D, Brooks DR, Funk VA. 1991. The Compleat Cladist: A Primer of Phylogenetic Procedures. The University of Kansas Museum of Natural History Special Publication Nr 19. Lawrence (KS): Museum of Natural History, University of Kansas.

About the Author(s): 
Alan Gishlick
c/o NCSE
PO Box 9477
Berkeley CA 94709-0477
gish@ncseweb.org