>>Aves 187 cell types 150 myr
>>Hominidae 210 cell types 5 myr
>
>This makes no sense at all. All of the data are derived from the study of
>extant groups. The assumption is made that these groups have not changed
>over the entire span of their history. Is this what evolution is about?
It's worse than that. The implication is that arranging extant groups in
order of complexity illustrates how evolution occurred, that each evolved
in turn from the one 'below'. A very old and unsupported idea, but one that
is apparently irresistible. There's no denying that evolution must have
begun with something simple, but there's no evidence for stretching the
concept this far.
--Cliff Lundberg ~ San Francisco ~ cliff@noe.com