Abscheulich!

Natural History, March, 2000 by Stephen Jay Gould

Agassiz proceeded in generally measured prose until he came to page 240, where he encountered Haeckel's falsified drawings of vertebrate embryology--a subject of extensive personal research and writing on Agassiz's part (see page 45). He immediately recognized what Haeckel had done, and he exploded in fully justified rage. Above the nearly identical pictures of dog and human embryos, Agassiz wrote: "Woher copiert? Gekunstelte Ahnlichkeit mit Ungenauigkeit verbunden, z.b. Coloboma, Nabel, etc." (Where were these copied from? [They include] artistically crafted similarities mixed with inaccuracies, for example, the eye slit, umbilicus, etc.)

At least these two drawings displayed some minor differences. But when Agassiz came to page 248, he noticed that Haeckel had simply copied the same exact figure three times (see page 46) in supposedly illustrating a still earlier embryonic stage of a dog (left), a chicken (middle) and a tortoise (right). He wrote above this figure: "Woher sind diese Figuren entnommen? Es gibt sowas in der ganzen Litteratur nicht. Diese Identitat ist nicht wahr." (Where were these figures taken from? Nothing like this exists in the entire literature. This identity is not true.)

Finally, on the next page, (see page 49) he writes his angriest note next to Haeckel's textual affirmation of this threefold identity. Haeckel stated: "If you take the young embryos of a dog, a chicken, and a tortoise, you cannot discover a single difference among them." And Agassiz sarcastically replied, "Naturlich--da diese Figuren nicht nach der Natur gezeichnet, sondern eine von der andern copiert ist! Abscheulich." (Naturally--because these figures were not drawn from nature, but rather copied one from the other! Atrocious.)

2. Haeckel's forgeries as irrelevant to the validity of evolution or Darwinian mechanisms (von Baer's contribution): From the very beginning of this frenzied discussion two years ago, I have been thoroughly mystified as to what, beyond simple ignorance or self-serving design, could ever have inspired the creators of the sensationalized version to claim that Haeckel's exposure challenges Darwinian theory or even evolution itself. After all, Haeckel used these drawings to support his theory of recapitulation--the claim that embryos repeat successive adult stages of their ancestry. For reasons elaborated at excruciating length in my Ontogeny and Phylogeny, Darwinian science conclusively disproved and abandoned this idea by 1910 or so, despite its persistence in popular culture. Obviously, neither evolution nor Darwinian theory needs the support of a doctrine so conclusively disconfirmed from within.

I do not deny, however, that the notion of greater embryonic similarity, followed by increasing differentiation toward the adult stages of related forms, has continued to play an important, although scarcely defining, role in evolutionary theory--but through the later evolutionary version of another interpretation first proposed by yon Baer in his 1828 treatise. In a pre-evolutionary context, von Baer argued that development, as a universal pattern, must proceed by a process of differentiation from the general to the specific. Therefore, the most general features of all vertebrates will arise first in embryology, followed by a successive appearance of ever more specific characters of particular groups.