Re: Ancestors [was: Re: And while on the theory of phylogenetic reconstruction...]

["T. Michael Keesey" <mightyodinn@yahoo.com>]

--- "Jonathan R. Wagner" <jonathan.r.wagner@mail.utexas.edu> wrote:
>     The real upshot is that the term basal ("at the base") implies some form
> of unequivocal directionality in a tree. While a rooted tree does have an
> unequivocal "up" direction, i.e., time, this directionality is relative
> among branches.

And if it's time that you're talking about, you might as well use "early"
instead of "basal".

Good points. It does seem to me that there is still one area where the term
"basal" is useful, and that's in describing characters, e.g. "bipedality is
basal for _Dinosauria_", "hair is a basal trait for _Mammalia_", "ectothermy is
the basal condition for _Amniota_", "monotremes retain the reproductive system
of basal _Mammalia_", etc.



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