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[On Friday, October 14, 2005, a previous witness, plaintiff Steve Stough, had to finish testifying before Kevin Padian took the stand.]
THE COURT: All right. Sir, that concludes your testimony. You may step down. Thank you. Exhibits --
MR. HARVEY: Your Honor, may I make a suggestion before you begin that?
THE COURT: Yes.
MR. HARVEY: That is that we have an expert witness, Dr. Padian --
THE COURT: And you're going to tell me you want to get moving?
MR. HARVEY: That's a dangerous thing to say to the Court.
THE COURT: No, that's fine. I know you have an expert and you want to get moving on the expert. So you want to reserve the argument on the exhibits until later?
MR. HARVEY: Exactly, Your Honor.
THE COURT: I'll rely on you then to remind me so that we get those in, and let's take your witness.
MR. WALCZAK: Your Honor, plaintiffs call Dr. Kevin Padian.KEVIN PADIAN, Ph.D., called as a witness, having been duly sworn or affirmed, testified as follows:
THE CLERK: If you could state and spell your name for the record.
THE WITNESS: My name is Kevin Padian, P-a-d-i-a-n.
THE COURT: You may proceed.
Q. Good morning, Dr. Padian.
A. Good morning, Mr. Walczak.
Q. Where do you live?
A. I live in Berkeley, California.
Q. What do you do there?
A. I am Professor of Integrative Biology at the University of California and a curator in the Museum of Paleontology.
Q. I'd like to direct your attention to what's been marked as Plaintiffs' Exhibit 292. Matt, could you put that up. Do you recognize this document?
A. It looks like my CV.
Q. Is this a reasonably accurate representation of your professional experience?
A. I believe that's a recent one, yes.
Q. I'd first like to focus on your educational background. And you have a bachelor's of arts degree from Colgate University?
A. Yes, sir.
Q. And you have a master's of arts in teaching. Is that correct?
A. That is right.
Q. What does that mean?
A. It means that I have permanent certification in the State of New York and several other states to teach life science in grades 7 - 12. And for this training, you take postgraduate courses in education and your subject major, whatever it happens to be, and you do intern teaching and you're certified to teach.
Q. And what was your subject major?
A. I majored in natural sciences at Colgate, and so I'm certified with life sciences.
Q. And have you ever used that degree to teach elementary or secondary school biology?
A. Yes. I've taught seventh-grade life science and biology, and I've taught two years of sixth-grade process science.
Q. And when was that?
A. That would be in the years '72 to '75.
Q. And after that, did you go back to school to get your Ph.D.?
A. I went to Yale for my Ph.D. after that, which I got in biology in 1980.
Q. And did you write a dissertation for your Ph.D.?
A. I did. That's required.
Q. And what was the topic of your dissertation?
A. The topic of my dissertation was on the evolution of flight and locomotion in the flying reptiles called pterosaurs, which lived during the age of dinosaurs.
Q. And where was your first professional appointment after graduating?
A. I went to Berkeley right after that as an assistant professor, and I've been there ever since.
Q. And what's your position there now?
A. I am a professor and curator, so a professor in the Department of Integrative Biology and curator in the Museum of Paleontology there.
Q. And what do you teach, Professor Padian?
A. I teach a variety of courses over 25 years. Some I don't teach anymore because the curriculum changes, but currently I teach and coordinate half of our upper division junior/senior courses in evolution. I teach an upper division course in the evolution of vertebrates. I teach a number of freshman seminars usually on dinosaurs. I teach a number of graduate seminars on topics that range from macroevolution to the history of evolutionary thought. Currently we're doing Darwin's Origin of Species.
Q. And you said a moment ago that your background and expertise is in evolutionary biology and paleontology. Could you tell us what those specialties involve?
A. Sure. Evolutionary biology is a broad field that ranges from the study of the changes through time of molecules to the changes in time of the whole history of life as it relates to the changes of the planet Earth through time, the whole solar system. And my specialty in this is what we call macroevolution. Within that, I focus principally on how major new adaptations begin in evolution.
Q. When you say "major new adaptations," what do you mean?
A. Well, about things like flight or how, for example, dinosaurs took over the earth. That's a great big change in evolution that happened about 225 million years ago. I work on problems like that.
And I also work on problems involving dinosaurs and general things about reading their footprints, their locomotion, again, how the age of dinosaurs got started. And I'm interested in the history of evolutionary thought, how people have conceived of the idea of evolution and how it's developed over time in the past 200 years.
Q. And is some aspect of what you just talked about paleontology?
A. Paleontology is the study of life of the past, generally put. And so when I say that I work on macroevolution, these are large changes that happened at a scale above the population level. So we usually have to look at them through time.
Q. And do you look at something called the fossil record?
A. The fossil record is where I spend a lot of my time.
Q. And what is the fossil record?
A. The fossil record is the record in the rocks of the remains of organic beings through time. It can take the form of bone, shells, footprints, trace fossils, all sorts of things.
And what we do is, we don't -- I mean, when you look at television documentaries, it normally focuses on people going out in the field and parking the truck and walking out in the Badlands and, you know, stumbling over bones someplace and finding that it's interesting in digging up and getting a skeleton and putting it in plaster and taking it back to the lab.
Q. It sounds like you have to have knowledge in many different fields.
A. Well, my department is called integrative biology for a reason, that we actually look at problems in a rather integrative way. That is, my work involves physiology, bone histology, which is the tissue form of bones and mechanics of growth, as well as fossils and geologic change through time.
Q. And are you still involved in research?
A. Oh, yes. Berkeley is a premiere research institution like Harvard or Yale or Penn State, and basically most of what we do is research and teaching. So as part of my job, I'm expected to produce a lot of peer-reviewed articles and books and things on a regular basis.
Q. And you've been doing research for 30 years now?
A. Yeah, roughly.
Q. And this is all on evolution and paleontology and the fossil record?
A. Oh, yes.
Q. And you mentioned that you've --
MR. WALCZAK: Is that a hint, Your Honor?
THE COURT: No. Inadvertent button push.
Q. You mentioned that you've published peer-reviewed research. Let me direct your attention to the top of Page 2 of your curriculum vitae, or I guess about a third of the way down. Now, it says there, Publications. What do you mean by that?
A. These are -- the list that I enclose with my CV here includes what we call peer-reviewed publications. And so these would be publications that have been sent out to our professional journals and, in some cases, to books that are edited by professionals again.
I don't know if you've gone through the concept of peer review much in the court, but by "peer review" we mean that if you publish -- if you have some research that you've produced and you want to get it published, you send it to a journal in the field, and the editor, who is an expert in the field, takes your manuscript and sends it to several experts that you can't choose and you don't know who they are. And --
Q. So you, as the author, don't know who is reviewing your articles?
A. That's correct. This is the anonymity of peer review. Ordinarily you don't know who these commentators are.
Q. What's the purpose of that?
A. Well, it's basically so that they can give a frank appraisal of what you're writing without worrying about whether they're going to offend you and, if you're a senior scientist, whether you're going to get mad at them or something. I don't know. But it's been a habit that's always been the case in the scientific field, certainly.
And the reviewers who look at your papers then decide whether you've followed the right procedures for going about the science, whether the methods you use are up to date, whether you've cited all the literature that's relevant, whether you've inferred or speculated on more than you should, or whether it's basically within the grounds of what is acceptable science.
Q. And so is everything that is submitted to a peer-review journal published?
A. Oh, no. A lot submitted to peer-review journals isn't published. It depends on the journal. On the journals on which I've been an editor, you have an acceptance rate of anywhere from 50 percent upwards or downwards to 30 percent, for example, in the ones I'm familiar with.
Q. And is there a -- what you might consider a hierarchy of journals for publication?
A. Yes, there are certain journals that pretty much every scientist in the world reads every week. Two of them in particular are Nature, which is published in London by Macmillan Journals, and Science, which is published in Washington every week by the American Association for the Advancement of Science, which is our sort of central public science organization in America.
Everybody reads those journals because they contain good review articles, but mainly the hottest sort of new research in all fields. They will also include news about new scientific developments not just in science but in education, industry, technology, even this court case, for example.
Q. And do they have a high rejection rate?
A. Oh, yes, they have a very high rejection rate. No more than about 10 percent of what's submitted to them even gets considered for publication.
Q. Now, is there something called -- is it an impact factor?
A. Yeah, there's a -- the Institute for Scientific Information produces a measure of how important journals are basically to the fields. Journals like Nature and Science have a very high impact factor. But they're general journals that everybody reads, and they're highly selective.
Some fields are smaller fields, they don't have much of an impact because they're not cited very much simply because the fields are small, but within the fields they might be very important. So you could have an impact factor that is relatively low, but in the field it's high because it's cited a lot for that field.
Q. And the way they measure this impact factor is to see how many times an article from that publication is cited thereafter?
A. That's basically it.
Q. And what journals have you published in?
A. Well, I've published in a lot of journals. My colleagues and I try to -- you know, you always try to go for the best journal in the field that you're writing for the people who would be the most interested in the research.
Sometimes I'm writing about dinosaur footprints, and I might try to publish in a journal that publishes a lot of footprint work. Other times, for example, when we've done our work on how fast dinosaurs grow, learning about this from the fine structure of their bone tissues, we've gone to Nature, we've gone to Paleobiology, we've gone to Journal of Vertebrate Paleontology, again, sort of the best journals in the field that we can target, depending on the scope and interest of what we're trying to do.
Q. Now, I note that by my count, you've got eight pages of peer-reviewed publications listed here in your curriculum vitae. Do you know how many peer-reviewed publications you are either an author or coauthor on?
A. It's 80 to 100. I don't keep a correct count.
Q. And have you included in this curriculum vitae non-peer reviewed publications?
A. I believe the copy that I gave the Court may have only the peer-reviewed ones. I have about another eight or ten pages of things like book reviews and popular articles, things in Scientific American and stuff like that. But I didn't include all those here. I may have included some of the books that I've authored or edited.
Q. Let's turn to -- I believe it's Page 9. And you've got a heading on books. And you are either the author or the editor or a contributor to these nine books?
Q. And just pick one. Tell us about your contribution to, for instance, the Encyclopedia of Dinosaurs, and what is that book?
A. The Encyclopedia of Dinosaurs was published by Academic Press, I guess in 1997. It's a standard reference work for the field. And my job, along with Phil Currie, my coeditor, was to organize and solicit the contributions to make sure all the relevant entries were covered, to read the manuscripts when they came in from the authors, if they needed changes, to suggest them or to make them.
And, in fact, as it turns out, I wound up writing about a sixth or a seventh of the book before publication just because of filling in the parts that were needed, as inevitably happens with reference works.
Q. And this is a book that would be found in your public library or your school library as a reference text on dinosaurs?
A. Yes. This book is cited by other scientists in their publications. It is in libraries for ordinary people to read. We tried to write it at a level that somebody that would have a general understanding of dinosaurs would do it. And then for the dino fans and freaks, they're going to pick it up, too, and enjoy it as much as the rest of us.
Q. Now, does something become science or accepted in science because it's published in a book?
A. Well, it depends on the book. When books are published, they may have a seminal influence, but simply because something is published in a book doesn't mean that it's science. I think that that's a question of its reception by the scientific community.
If somebody writes a book and nobody reads it, is it influential? And the answer would be no. And if somebody writes a book but claims it's science and it's not cited by scientists, it doesn't stimulate scientific research and the ideas in it are never brought to peer review, then the answer is probably not much, because we depend on peer-review discussion of ideas and research results in order to further the progress of science.
Q. So anybody can write a book and proclaim that they have a new scientific theory, but the test really is whether it's ultimately accepted by a large part of the scientific community?
A. Yes. And here I think the term "theory," again, has to be looked at the way scientists consider it. A theory is not just something that we think of in the middle of the night after too much coffee and not enough sleep. That's an idea. And if you have a hypothesis, it's something that's a testable proposition, you can actually find some evidence that will help you to weigh it one way or the other.
A. A theory, in science, as maybe it's been pointed out in court, I don't know, in science means a very large body of information that's withstood a lot of testing. It probably consists of a number of different hypotheses, many different lines of evidence. And it's something that is very difficult to slay with an ugly fact, as Huxley once put it, because it's just a complex body of work that's been worked on through time.
Gravitation is a theory that's unlikely to be falsified even if we saw something fall up. It would make us wonder, but we'd try to figure out what was going on there rather than just immediately dismiss gravitation.
Q. Is the same true for evolution?
A. Oh, yes. Evolution has a great number of different kinds of lines of evidence that support it from, of course, the fossil record, the geologic record, comparative anatomy, comparative embryology, systematic, that is, classification work, molecular phylogenies, all of these independent lines of evidence.
Q. We're going to talk a little bit more in detail about some of those concepts in just a couple of minutes. Your expertise has been recognized by professional societies and scientific journals in a sense that you have been an officer or a committee chair on a number of prominent scientific associations?
A. Yes, if that's a measure. My work is published in the organs of scientific societies, their professional journals. I've served as an officer in a couple of societies and committee member, and I've been on the editorial board of a number of peer-reviewed journals in our field.
Q. Matt, if you could turn back to the first page of Dr. Padian's CV under Professional Service. Now, it appears that you've been an editor on the editorial board of more than a half a dozen journals. Can you tell us what it means to be an editor of a journal?
A. It generally means that when manuscripts come in, the chief editor will send them to you either for review yourself or for deciding whether they should be reviewed by people. Or if you send them out to review, you might gather the reviews from the referees and determine the merits of the manuscript in question.
Q. And I note that you've had a couple of stints as editor of the Journal of Vertebrate Paleontology. Is that a prestigious journal in your field?
A. That is, in our field of just those paleontologists that run around the rocks and look for the remains of old animals with backbones, yes, that's our primary international scientific organization. Paleobiology is probably the premiere journal in the field of paleontology that works on macroevolution, which is one of the things that interests me.
Q. And you were the editor of Paleobiology for six years?
A. I was one of the editors on the editorial committee, yes.
Q. And you were also on the editorial board of Geology and the Proceedings of the Royal Society of London?
Q. Dr. Padian, have you had any experience with high school or elementary school curriculum development and teacher training?
A. Yes. Since I've been in California, since the mid 1980s, I've worked in several capacities for the State Department of Education in California on various panels and committees.
Notably, I guess, I was one of the people who wrote and edited the state science framework for K-12 schools in 1990. And this is the central document that embodies science education for the state. It's the document against which districts and other organizations will develop their curricula locally.
And my role there was to write about guidelines for the -- explaining what science is, the nature of science, explaining the goals for K12 in the life sciences and for some of the earth sciences and several other parts of that.
In addition, I guess I've served three times on what we call the instructional materials evaluation panel as a scientific member. California is an adoption state, which means that it's one of 23 states for which the state actually selects which textbooks can be used by local districts and for which state funds can be spent.
And so it's kind of a quality control that educators and content area specialists like scientists or historians or mathematicians will get together and evaluate textbooks and things submitted. And then the question is whether these are -- which ones pass muster and which ones don't, and that's what you can use state funds to buy.
Q. And you've been involved in that for several years?
A. Three times.
Q. And do you have familiarity with creationism and intelligent design?
Q. And just tell us a little bit about that. What's your history of involvement?
A. Well, California has an interesting history with respect to the creationist movement, I guess we might call it creation science and related fields.
The Institute for Creation Research in Southern California has been very active since the early 1980s and various kinds of legal and social processes that have come out of objections to the teaching of evolution in California have mirrored what's happened in other states, as well.
And so early on in the 1980s I was one of a number of scientists who were involved in trying to clarify evolution and related science to the public and to advise the Department of Education and other bodies about it and to talk generally to the public about what evolution was.
And these organizations and sort of committees of correspondence, as they were called then, eventually morphed into what became the National Center for Science Education which I've been president of for some years.
Q. I'm sorry, you said you're president of the National Center for Science --
A. National Center for Science Education.
Q. Dr. Padian, can you tell us a little bit about the history of paleontology and its importance to evolution?
A. Sure. Paleontology, the idea that you're finding rocks that have the remains of ancient life in it, has been around actually in some form or another since the 1500s and 1600s when people first started to understand that these were actually the remains of organisms that were dead and not simply sports of nature or some kind of sculptural-looking accident.
The understanding of fossils really began to mature in the late 1700s when people realized that these were the remains of dead creatures that were not coming back, they were extinct. And the upshot of this meant that ideas about the philosophy of nature began to change as the enlightenment developed.
By 1800, you had people in both England and France developing systems of looking at the order of the rocks through time, moving up through a section, that could be correlated from one area to another. The same sequences of rocks were appearing. These were used in England, for example, by civil engineers to dig canals and to show them where reliably they could find the right rocks to dig canals through.
Part of these indications were by the fossils that they contained which also went up in the same sequence every time. And this resulted in the first real geologic map of England, which was produced in about 1800. So we're already talking about using fossils in a very forensic sense, that is, to help dig canals, but using them as an index for mapping geologic -- we call them strata or outcrops all over England. A similar development of the idea was taking place in France at the time and also in Germany.
So the idea that there was a progression of fossils in rocks from the oldest to the youngest going up through a section of rocks is really quite old. And it was developed, in a sense, that had nothing to do with any ideas about evolution. It was just seen as the progression of fossils through time.
Q. And so what you've just told us about is taking place before Charles Darwin published his Origin of Species?
A. Oh, yes. Darwin doesn't publish the Origin of Species until 1859. The geologic map of England is being done by 1801, and already by 1846 they have a pretty good idea of the diversity of fossils through time.
Q. So was Darwin trying to explain the history of life or the fossil record?
A. No, he really wasn't. Other people were doing that at the time, including people like Richard Owen. What Darwin was doing was proposing a mechanism for how change through time could occur in a lineage of organisms, and he called that natural selection.
He made an analogy with what he called artificial selection, which is what breeders do every day in selecting plants and animals for the characteristics that we admire or want to use for various purposes.
Q. Now, we've had, I guess, testimony in this case where people seem to be using terms in different ways. Could you distinguish for us the way science uses the term "natural selection" from "evolution of life"? I mean, is there a distinction?
A. Yes. "Evolution," of course, refers to change through time in a general sense. Darwin's own definition is descent with modification, which is probably still the best one.
Natural selection is a mechanism, a process that accounts for a lot of that change, but it needs to be distinguished from evolution, per se, because there are a number of mechanisms, as Darwin noted, including sexual selection, which is another term he invented, a concept that he invented, as he did so many things, and it's just one mechanism for life to change. It's not the whole thing. Darwin was very clear on that in his writings.
Q. And can you distinguish evolution of life, the term "evolution of life," from the term "origin of life"?
A. Sure. And that's a common conflation in popular parlance. Evolution of life is essentially the whole enchilada. It's everything from the first organisms that appeared right up until the organisms that are alive today. That whole procession of things, all the patterns and processes that are involved in it, we would call the evolution of life.
"Origins" is a trickier phrase. The origin of life we expect, as Darwin said in 1859 -- the last paragraph of The Origin of Species refers to one or a few forms being the original embodiment of life. But today we look at the genetic material, DNA, RNA, and its genetic components, and scientists reason from this that they are so complex and so similar that they must have had a common origin. And this is the origin of life question.
That's separate if you talk about, like, origin of birds or origin of mammals or origin of the middle ear. Those things are part of the progression of life that's already established. They aren't something new that happens all over again that's, in other words, abruptly or specially put in there. They're just part of something that's already happening that now is modified to become something else.
Q. So as scientists would use "origin of life," that would be sort of first life?
Q. Now, it seems that genes and molecules are getting much of the attention today when you're talking about evolution. Is it still important to study comparative anatomy, fossils, geology, paleontology? I guess another way to say it, are you still relevant?
A. I'm a fossil like everybody else. No, genes and molecules get a lot of press, and deservedly so. The research on them has been amazing over the past half century. The new discovery has just come at an incredible rate. They're just revealing all sorts of new things about the world we never could have imagined. We could have hoped we could have known, but we wouldn't have known how.
But, oddly enough, the most recent great advances in biology are coming with the integration of this new molecular evidence with what we already know from comparative anatomy, from fossils, and from geology.
An example I could give you is like the hottest area in biology today is called evo-devo or evolutionary developmental biology. Evo-devo is not a rock group. And the thing about it is that the whole premise of evo-devo is that we are now understanding a lot more about the genes that actually code for the development of organisms. That is, we know the genes that make you line up in a front-to-back axis and make your limbs sprout and make you have wings instead of hoofs or whatever it happens to be.
These are under the command of a relatively well-organized system of genes that are universal among a great many organisms. And you can even transplant parts of these into other organisms, and they'll work properly, which is really amazing.
And why paleontology and evolutionary biology is relevant to this is because, for one thing, in the fossil record we see a lot of forms that are not present in any kind of shape today. Configurations of hands and wings and skulls that we can see by examination of the genetic structure and functions of development actually are produced in certain ways and they mimic what we see in the past.
Q. So is it fair to say that molecular biology today reinforces what you find in paleontology or integrative biology?
A. Oh, yes. The molecular biology of the 1960s and '70s was very strongly what we would call reductionist. That is, they were looking for the little, tiny workings, because they were able to do so, of genes and structures in the cells and chromosomes, and that was really amazing.
But, you know, in a sense, all that work is figuring out how the carburetor goes, you know, what are all the parts here. But they don't lose sight of and it doesn't change the importance of, you know, how you drive the car, what the purpose of the car is in terms of running down the road and operating on the internal combustion engine. And that's where the evolution comes in.
Q. I want to ask you one other question coming back to natural selection, and you said that is a mechanism for driving evolution.
Q. And is that a mechanism that is widely supported by the scientific community?
A. Oh, yes. Darwin proposed it at the same time that Alfred Russel Wallace came up with it in 1858. And since then natural selection has been tested in the wild and in laboratory populations by a great number of scientists. And there are many books written that summarize this research, and the understanding of natural selection is primary to understanding population biology and evolution.
Q. Now, next week an expert for the school district, Dr. Behe, are you familiar with him?
Q. He's going to testify. And Dr. Behe has claimed that it is not possible to observe natural selection in the fossil record. And is that true, and, if so, is the fossil record relevant to evolution?
A. Dr. Behe and some of the ID proponents characterize evolution, Darwinism evolution, as they call it, as random mutation and natural selection alone. And natural selection is important, but it's not the only process. Random mutation is a whole other problem in language. But natural selection can be observed in the fossil record in a different way than we'd see it in populations.
When Darwin developed his idea of natural selection, he's looking at individuals running around out there. He's saying that an individual horse is going to be able better to escape a lion than another horse. That horse is going to live longer, produce more offspring with the same characteristics, and those will be passed on to the next generation. So this is an idea about individuals.
Now, the problem is, when we go out to the fossil record, if we have a nice fossil deposit here of snails or clams or whatever it happens to be and you've got, you know, many local fossils, fossil deposits which you can find things like this, you know, we can't tell whether a particular fossil clam was better adapted than the guy who is dead next to him. We can't measure how many successful offspring he had. We just simply don't know. We don't know anything about the reproduction of fossils, individual organisms. And so in that sense, we're not looking at that level of natural selection.
But as everybody knows, we have a concept in evolution called "adaptation," which is sort of the main thing that drives the origination of new sort of types of organisms, the way that they get around in the world. And this notion of adaptation, by definition, is shaped by natural selection.
And my job is to look at macroevolution, and I focus on how new adaptations get going. So I study natural selection all the time in its ramifications for the development and improvement of all these complex adaptations that click in piece by piece in fossil animals and are shaped and preserved by natural selection.
Q. So the fossil record, in fact, helps to support the whole concept of natural selection?
A. In fact, it's indispensable to it, because we could look at natural selection in populations today, but our compass for looking at populations today is on the order of years, maybe decades, in some cases centuries.
A. A trend that we see today might reverse itself. It might be just sort of a drift or a random fluctuation, a temporary change, but in the fossil record, you see change through the big time. This is deep time, we call it. This is like mega history.
MR. WALCZAK: Your Honor, I was thinking about taking a break now. It might be an opportune time.
THE COURT: Why don't we do that. Let's take a shorter break than we've been taking so that we can keep moving with this witness. We'll take a 15-minute break at this point, and we'll return with Mr. Walczak's continued direct examination of this witness. We'll be in recess.