Does ontogeny tend to recapitulate phylogeny?

Answer 1

We recapitulate the embryo development of other animals, not the mature development. This is a common misunderstanding of Hackle's work. Only is that sense would it be valid. Think of it; the embryological development is quite conserved and built upon in organisms. The mature recapitulation would be considered preformation; which is refuted.

Answer 2

That's the theory. The support for it is certainly not universal. There does not seem to be a reason for the foetus to look like animals we have had common ancestors with, eg fish, amphibians etc. I can understand how human foetuses can look like other mammals. But perhaps we just haven't learned enough about it yet.

Edit: Sorry, as johnmcn49 pointed out: I was referring to embryos of other animals such as fish, not to the mature forms. I should have been un-ambiguous

Answer 3

yes

Answer 4

absolutely, I just had my r pinkie stitched.