Adaptive value (was Help required - Selaginellaceae)

[Curtis Clark]

At 11:59 PM 7/27/99 -0400, MAGarland at AOL.COM wrote:
>Does this mean that you can't ever know anything about the adaptive value
>of the cell nucleus, multicellularity, sex, animal limbs, or anything else

>older than 400 million years?

Yes and no. We can see how multicellularity, sex, and perhaps limbs are
adaptive in specific organisms today, by comparison with relatives that
lack them (I would challenge anyone to come up with a good adaptive
explanation of the nucleus in modern terms, however). But that tells us
nothing about the original adaptive reason (or lack thereof) for the
character. IMHO the ligule in Selaginella is vestigial; I imagine that one
might find a species or two in which it serves some function. But none of
that addresses why there is a ligule.


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Curtis Clark                  http://www.csupomona.edu/~jcclark/
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