Selaginaceae are now beyond evolutionary examination

[Daniel Janzen]

Animals have had legs for several hundred million years.  Does this put any
consideration of their original adaptive value effectively out of reach?

Dan Janzen





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>Date:         Tue, 27 Jul 1999 17:56:32 -0700
>Reply-To: Curtis Clark <jcclark at CSUPOMONA.EDU>
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>From: Curtis Clark <jcclark at CSUPOMONA.EDU>
>Subject:      Re: Help required - Selaginellaceae
>To: TAXACOM at USOBI.ORG
>
>At 05:46 PM 7/27/99 +1200, john steel wrote:
>>        Any function for the "ligule" which occurs at the base of
>>        the microsporophyll below the sporangia in Selaginella?
>
>The ligule is shared by the major clade that contains the Selaginellopsida
>and Isoetopsida (including the Lepidodendrales), and so goes back maybe 400
>million years. That puts any consideration of its original adaptive value
>effectively out of reach. :-)
>
>
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