Adaptive value (was Help required - Selaginellaceae)

[MAGarland at AOL.COM]

 jcclark at CSUPOMONA.EDU writes:

> 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. :-)

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?

Mark A. Garland
Florida Department of Environmental Protection