Claim CB704:
Human embryos do not have gill slits; they have pharyngeal pouches. In
fish, these develop into gills, but in reptiles, mammals, and birds, they
develop into other structures and are never even rudimentary gills.
Calling them gill slits is reading Darwinian theory into the evidence.
There is no way gill slits can serve as evidence for evolution.
Source:
Wells, Jonathan, 2000. Icons of Evolution, Washington DC: Regnery
Publishing Inc., pp. 105-107.
Response:
- The pharyngeal pouches that appear in embryos technically are not gill
slits, but that is irrelevant. The reason they are evidence for
evolution is that the same structure, whatever you call it, appears in
all vertebrate embryos. Agassiz (not a Darwinist himself) said, "The
higher Vertebrates, including man himself, breathe through gill-like
organs in the early part of their life. These gills disappear and give
place to lungs only in a later phase of their existence" (Agassiz
1874).
Darwinian evolution predicts, among other things, similar (not
identical) structures in related organisms. That pharyngeal pouches in
humans are similar to pharyngeal pouches (or whatever you call them) in
fish is one piece of evidence that humans and fish share a common
ancestor.
References:
- Agassiz, Louis, 1874. Evolution and Permanence of Type, reprinted in
Hull, David L., 1973, Darwin and His Critics, Cambridge, MA:
Harvard University Press, p. 440.
Further Reading:
Gilbert, Scott F., 1988. Developmental Biology, 2nd ed. Sunderland MA:
Sinauer Associates.
created 2001-2-17, modified 2003-5-22
