apes and humans

Helen, many invertebrates have larger genomes than vertebrates. Not that it matters. The evolution of vertebrates (and all organisms) is not about de novo appearance of new things, but the recruitment of old things to new uses.

It is perfectly consistent, and not surprising to scientists, that this be true on the genetic level as well as in anatomical details.

Why would you expect brand-new genes for legs, when it is so obvious that sarcopterygian fish already had genes for femur, tibia, fibula, tarsals and phalanges?

If this was not true, evolutionary theory would have some explaining to do.

 

And recruitment and regulation (especially in developmental expression) are two of the reasons why the oft-dissed principle of recapitulation has a core of truth.

It is true that the role of non-genetic developmental influences (e.g. egg cell membrane) was somewhat neglected until recently. But embryologists are active in this area.

-Neil

 

No, we didn't. Your error was to assume that there could be no evolution in regulatory genes.

We know that isn't the case.

 

[snip Helen's post showing new information on one way things evolve]

Cool, more evidence for evolution. Thanks. It's good to know we have learned an additional way that new traits can evolve, through changes in the ways particular genes are expressed.

Now, why again do humans and apes share very specific mutations in exactly the same way?

 

It appears to me just reading the material as filtered through Helen that what might be happening is (a) only the genes are being compared, the non-functional part of the DNA is being ignored and (b) whenever a gene differs - say gene 1 is AABAABAABAAB and gene 2 is AACAABAABAAB - then its counted as a 100 per cent difference for that gene.

But the whole thing is preliminary; further analysis will no doubt shed more light.