The Case of the Vanishing Embryos

Wyoming state welcome sign, along Interstate 80, entering from Utah. Photograph by ErgoSum88 via Wikimedia Commons.Unless you are middle school embryology? Currently under public review in Wyoming is a new proposed draft of state science standards. Wyoming, of course, achieved a degree of ignominy with regard to state science standards in early 2014, when a footnote in the state’s budget for 2014–2016 precluded the use of state funds “for any review or adoption” of the Next Generation Science Standards. Why? The author of the footnote, Matt Teeters, complained that the NGSS “handle global warming as settled science,” adding, “There’s all kind of social implications involved in that that I don’t think would be good for Wyoming.” There was a swift outcry, with educators, scientists, clergy, and the general public all over the Equality State protesting the decision, and the legislature—sans Teeters—reversed its decision in early 2015. The Wyoming state board of education, however, decided not to adopt the NGSS outright, instead asking a committee of Wyoming science educators to devise a new set of science standards for the state.

Previously, the committee recommended the adoption of the NGSS, so it’s not particularly surprising to discover that the new draft of science standards bears a close resemblance to the NGSS. There is, however, a conspicuous omission. Where the NGSS (in MS-LS-4-3) expect students to:

Analyze displays of pictorial data to compare patterns of similarities in the embryological development across multiple species to identify relationships not evident in the fully formed anatomy. [Clarification Statement: Emphasis is on inferring general patterns of relatedness among embryos of different organisms by comparing the macroscopic appearance of diagrams or pictures.]

the Wyoming draft omits the standard altogether, offering by way of rationale the following four points:

  • The Recapitulation Theory (Biogenetic Principle) is no longer scientifically valid.
  • The standard was written in a way that overlapped with curricular decisions.
  • Developmental appropriateness for younger middle-school students is questionable.
  • Removal does not affect the learning progressions.

I am not sure what the second point means; no evidence is offered for the third point; and the fourth point is a little mysterious, given that the “order of appearance of structures in embryological development” appears later in the draft (in HS-LS4-1).

It is the first point that interests me, however. The authors of the Wyoming draft are correct in saying that Ernst Haeckel’s so-called biogenetic law—encapsulated in the gnomic slogan “ontogeny recapitulates phylogeny”—is not scientifically accepted. But they are wrong in inferring that embryology is no longer regarded as a source of evidence about evolutionary relationships, which the omission of MS-LS-4-3 in effect suggests. There is a long-standing creationist tradition of impugning Haeckel for his controversial illustrations of embryos—which Nick Hopwood, in his Haeckel’s Embryos (2015), describes as “the most fought-over images in the history of science”—and extending the attack to embryology as a source of evidence about evolution altogether. It seems that the authors of the Wyoming draft are, if not endorsing the tradition, at least succumbing to it by censoring the standard in anticipation of creationist objections. It is, as it were, the Haeckler’s veto.

The first point in the rationale for omitting MS-LS-4-3 contains a link to a page in Understanding Evolution, the invaluable website run by the University of California Museum of Paleontology, about Haeckel’s views on evolution and development. The discussion there, as you can see for yourself, is purely historical, not aimed at discussing anything that would be presented as current science in today’s classroom. Elsewhere, Understanding Evolution is quite clear about the importance of embryology in contemporary evolutionary biology, especially in the burgeoning field of evolutionary developmental biology. But don’t take my word for it. I asked Lisa D. White, the director of education and outreach for the museum, to comment. She replied:

The UC Museum of Paleontology is in full agreement that:

(1) Neither the specific information included on the UCMP Understanding Evolution website about Haeckel’s Biogenetic Law ( nor any other material posted on Understanding Evolution should be understood as implying that embryology is not a distinctive and important source of information about evolutionary relationships.

(2) Because embryology is a distinctive and important source of information about evolutionary relationships, it is absolutely scientifically appropriate for state science standards to contain NGSS’s MS-LS4-3 or the equivalent.

So the expert source cited in the service of omitting the standard about embryology wholeheartedly disagrees. As would any expert source. For example, Michael Richardson, who famously compared Haeckel’s drawings with modern photographs in 1997, wrote in 1998, “Data from embryology are fully consistent with Darwinian evolution. … Early versions show young embryos looking virtually identical in different vertebrate species. On a fundamental level, Haeckel was correct: All vertebrates develop a similar body plan (consisting of notochord, body segments, pharyngeal pouches, and so forth). This shared developmental program reflects shared evolutionary history. It also fits with overwhelming recent evidence that development in different animals is controlled by common genetic mechanisms.”

If you live in Wyoming, you can still comment on the standards. It would be nice if you called for the restoration of MS-LS-4-3, of course, but you should also make a point of commending the standards that present evolutionary biology, deep time, and climate change correctly and forthrightly. And you should definitely encourage those involved in the revision of the science standards to present science as it is understood by the scientific community without any compromises to mollify ideological opponents of science. If you have a special stake in science education, be sure to mention it. If you are a parent, for example, talk about your desire for your children to learn about science properly; if you are a K–12 teacher, talk about your professional responsibilities to teach about science properly; if you are a college instructor, talk about the importance about preparing students to excel in college; and so forth. It’s a great way to support the education of Wyoming’s embryonic scientists.