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Re: Dinosaur Diversity Analyzed



Interesting little paper from Mike Taylor (who gave a link for downloading a pdf in his last posting), with nice graphics.
Repeatedly emphasizes that the statistics he gives should be approached with caution for a whole lot of reasons.


Sampling bias an obvious one: the very large number of dinosaur taxa known from the United Kingdom (about (guesing and doing mental arithmetic) 1/700 of the Earth's land area), for xample, surely reflects the long history of geology as a science there!

Are there any good ways to estimate sampling bias? Paticularly: any ways, using available infformation, to estimate which parts of the Mesozoic have been better-sampled than others? For instance... Somewhere in the literature there must be a reasonably complete and compact list of all the dinosaur fossil sites that have been worked in the last century or so: are some ages much better represented than others? This would give a very crude indication-- site briefly surveyed by a government geologist when the country it is in was a colony would be counted as equivalent (for sampling) to one of the extraordinarily rich sites that have been extensively excavated over decades, but I suspect getting a more refined measure of sampling out of the published literature would be very difficult.

(I know attempts at estimating sampling bias have been made in connection with the question of whether dinosaur diversity was declining in the late Cretaceous...)

--

Allen Hazen
Philosophy Department
University of Melbourne