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Re: What the fossil record tells us about trends in pterosaur diversity
David Peters wrote:
I disagree. Phylograms are particularly instructive.
We can produce a topology, certainly, but if the results of Butler et
al. are accurate, then attempts to estimate ghost lineage lengths and
overall time calibrationsare more or less completely muddied, meaning
that you still can't produce an accurate estimate of diversity through
BTW: various pterosaur genera of all shapes, sizes and niches were
going extinct left and right long before the advent of birds.
It seems that way, but again, if the apparent diversity of pterosaurs
in each interval is entirely taphonomic, how do we know that's actually
true? It might be that only a very few of those apparent extinctions
are real, and we're truncating the last occurance dates for many
Michael Habib, M.S.
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205
(443) 280 0181