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Re: GRACILITY IN TETRAPODS
email@example.com (Ronald Orenstein) writes:
>One thing to think about: what are the different selective factors leading
>to gracility as opposed to simply smaller size? If, for example, food
>becomes limiting so there is an advantage to reducing body weight, eithr
>gracility or dwarfism would do the trick - yet on islands, for example,
>dwarfism seems the commoner result.
Actually, it's just the opposite...
Gracility arises in "boom times", a response to a sudden increase in the
availability of resourcess, NOT a reduction of resources. Gracility
is also accompanied by such changes as early sexual maturity, and in
some cases, larger litters/more eggs. A good discussion of
gracile vs. robust species variants can be found in the excellent
Calvin, William, "The Ascent of Mind", 1990 Bantam Books.
Although in the book Calvin is talking about early hominids, most
of the concepts are transferrable to dinosaur species.
Achut Reddy So many fossils... so little time!