clues to ligule origins

[John Grehan]

 All of this is in the literature and
>suggestive of the original 1800s hypothesis of a moisture providing system.
> Maybe protecting the apex or sporangia from drying.  It is interesting
>that Curtis Clark and John Grehan, without having a clue regarding the
>specific anatomical or cytological literature, can "discuss'' the evolution
>of a particular structure.
>
>Fred Rickson

Glad to know that its interesting, but as for not having a "clue" I would
respond that the issue I have written on is less about the evolution
of a particular structure than it is about the conceptual framework that
determines the homology of the ligule and which in turn may
influence the development of evolutionary models that identify an
ancestral state for the structure in question (ligule).

The functional hypothesis referred to by Fred also
involves no necessary insight into the origin of the ligule, or
what may be understood about its origin unless one has
decided that this functional attribute was present when the
ligule first appeared, and that this function was necessarily
the factor leading to the spread of this novelty (ligule) through the
ancestral population.

John Grehan