[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Exaptation

On the subject of exaptation and other relevant things.....

This is all very interesting, but I am missing something here, perhaps I
overlooked it.  How long does it take for these characters you all discuss,
for any of the dinos you discuss, to evolve?  What is the time, in years,
that it took for two closely related species, you pick em, I don't know that
much about paleontology, to diverge from their common ancestor.  I think
pattern formation can occur in the blink of an eye, like less than 100,000
years.  The Cambrian explosion shows that most phyla of bilaterally
symmetrical metazoans evolved in an 8 to 9 million year period.  After that
radiation, all extant phyla are recognizable.  So the characteristics
separating major groups of tetrapods could have occured over a very short
period of time, right?  Like synapsids and diapsids? Dinosaurs and birds?
Birds and mammals?  The accumulation of pattern differences could actually
lead one to believe that birds and mammals, for instance, are farther apart
than they truly are.

-Chip Pretzman