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How Did We Get Here?

Letter 2
Phillip E. Johnson, November 19, 1996



Dear Kenneth

The Lennart Nilsson photographs that provide the occasion for this discussion illustrate the development of the embryo in the womb—NOT the historical process of how we get humans or animals in the first place. These very distinct subjects are often confused. For example, Darwinists long maintained that "ontogeny recapitulates phylogeny," meaning that the human embryo evolves through a fish stage and then through amphibian and reptilian stages before it takes on its human form.

This recapitulation doctrine was discarded by science long ago, but it survives in popularizations. For example, the Life magazine article accompanying the Nilsson photographs admitted that science has repudiated recapitulationism—but nonetheless argued that features like supposed "gill slits" provide a "hazy" version of evolutionary history. But human embryos never possess gills, either in embryonic or developed form, and the embryonic parts that suggest gills to the Darwinian imagination develop into something entirely different.

The recapitulation thesis is false, and viewers of the Nilsson photographs should be warned against any insinuations that the photos illustrate a replay of evolutionary history. Agreed?

A related misunderstanding says that animals are much alike as early embryos, and become dissimilar later in embryonic development. Darwinian theory reasons that early embryonic similarities reflect common ancestry, with evolutionary differences emerging later in development. The Nilsson series appears to support this theory with photos of vertebrate embryos in mid-development that look similar in shape—but this overlooks the crucial fact that the embryos develop to that stage by very different means.

The early stages of vertebrate development are actually radically dissimilar. If early developmental similarity is the test of common ancestry, then vertebrates do not share a common ancestor.

So the Nilsson photos do not provide evidence of common ancestry, and they certainly do not illustrate the Darwinian process of mutation and selection. What these misunderstandings actually illustrate is how overly enthusiastic Darwinists have sometimes misled themselves. I note that you do not rely either on echoes of recapitulationism or on early embryonic similarities to prove common ancestry, and so perhaps you agree with me so far.

Now to the evidence you do cite. The mutation/selection mechanism has never produced anything more impressive than variations in pre-existing populations (microevolution). The claim that natural selection can create new complex organs has been challenged by the evidence of irreducible complexity at the molecular level. (Should we discuss Darwin's Black Box, by Michael Behe?) The fossil record also remains on the whole pervasively anti-Darwinian, even though the paleontologists have tried as hard as the embryologists to impose a Darwinian interpretation. Where are the common ancestors of the animal phyla? Where is the testable mechanism for macroevolution?

Did we evolve? Maybe, but very little is known about the mechanism and much misinformation has been spread in an effort to prove, in the words of your textbook, that "evolution is random and undirected." How do you know that?



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