Haeckel's practices, etc.

pnelson2@ix.netcom.com
Wed, 28 Oct 1998 11:57:41 -0600 (CST)

Kevin L. O'Brien wrote:

>Haeckel committed no fraud.

On the contrary, Haeckel's practices were highly questionable,
even by the standards of the time. The distinguished historian
of embryology Jane Oppenheimer (1987, p. 134) notes, for instance:

It was a failing of Haeckel as a would-be scientist that his
hand as an artist altered what he saw with what should have
been the eye of a more accurate beholder. He was more than
once, often justifiably, accused of scientific falsification,
by Wilhelm His and many others. For only two examples, in
_Anthropogenie_ he drew the developing brain of a fish as
curved, because that of reptiles, birds, and mammals is bent.
But the vesicles of a fish brain always form in a straight
line. He drew the embryonic membranes of man as including
a small sac-like allantois, an embryonic organ characteristic
of and larger in reptiles, birds, and some nonhuman mammals.
The human embryo has no sac-like allantois at all. Only its
narrow solid stalk remains to conduct the umbilical blood
vessels between embryo and placenta. Examples could be
significantly multiplied.

Even more dubious was Haeckel's use of the same printing blocks to
illustrate embryonic stages in different species. As the Polish
physician and historian of science Ludwik Fleck (1979, p. 36)
observes,

When Haeckel, the romantic, high-spirited champion of truth,
wanted to demonstrate his ideas about descent, he did not
shrink from occasionally using the same blocks for the
illustration of different objects such as animal and
human embryos which should look alike according to his
theory. His _History of Natural Creation_ abounds with
biased illustrations appropriate for his theory.

The Swiss embryologist Gunter Rager has reproduced some of these
illustrations in his 1986 article, "Human embryology and the law of
biogenesis" (Rager 1986). He writes:

On page 248 of the _Naturliche Schopfungsgeschichte_ (1868)
Haeckel published 3 figures which were supposed to show the
embryos of a dog, a chick and a turtle, respectively. These
3 figures are completely identical. Even the asymmetry of
the 10th pair of somites and the number and length of lines
in...each of the figures are the same. (1986, p. 451)

Rager gives other examples from Haeckel's publications of the
same practice, calling the illustrations "faked material" and
"cheating tricks" (1986, pgs. 449 and 452). Whatever label one
wants to attach to Haeckel's practices, there is no reasonable
defense for using exactly the same diagram to illustrate three
different species.

Kevin L. O'Brien also wrote:

>On the contrary, Haeckel's law (which would be better called
>von Beer's law) is very much alive and well. In a basic fashion,
>ontogeny really does recapitulate phylogeny.

Von Baer's laws -- not "von Beer's" -- differ profoundly from Haeckel's.
Indeed, von Baer formulated his generalizations precisely in opposition
to the sort of recapitulation Haeckel favored. In any case, neither
von Baer's laws, nor Haeckel's, are reliable generalizations today
about the patterns of metazoan ontogeny. Looking simply within the
vertebrates, for instance, the earliest stages of development are
strikingly different (e.g., between an amphibian, a chick, and a mammal).
For further discussion, see Raff (1996) or the latest edition of Scott
Gilbert's developmental biology text, and the literature cited therein.

Paul Nelson

Fleck, L. 1979. _Genesis and Development of a Scientific Fact_.
Chicago: University of Chicago Press.

Oppenheimer, J. 1987. Haeckel's variations on Darwin. In _Biological
Metaphor and Cladistic Classification_, eds. H.M. Hoenigswald
and L.F. Weiner. Philadelphia: University of Penn. Press.

Raff, R. 1996. _The Shape of Life_. Chicago: University of Chicago Press.

Rager, G. 1986. Human embryology and the law of biogenesis. _Rivista
di Biologia - Biology Forum_ 79:449-465.