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Re: 2002 (bio)ontology papers AND Jim Carey's ongoing project on extinctions



>     I would like to take this opportunity to interrupt the rooster struttings I have read on the DML <
Funny...
Anyways, the seminar certainly does sound interesting, but I'm not so sure about the intent of the host, nor his expertise (as David pointed out in an early post)...whether those mistakes are genuine or just "hype", I'm not too sure. Anyways, I don't think anyone doubts the importance of biology and ecology in the K/T event; that's what we're talking about. What happens of biological communities with said even X (the impact) happens...instead of posturing, why don't we discuss ecological effects (I thought we already were)...
Peace,
Rob
 
Student of Geology
P.O. Box 20840
Flagstaff, Az. 86011
http://dinodomain.com
http://www.cafepress.com/robsdinos
AIM: TarryAGoat
 
re: extinctions, and to share with the non-Marvel Comical Kiddie crowd the upcoming, eight week seminar to be directed  by Jim Carey in the winter of 2003 at the University of California, Irvine.  I have had the honour of playing a small part in sharing with Jim bibliographical citations of important past/present papers on the ecology of dinosaur extinctions, so to speak, from my 1954 to date immersion in the study of (paleo)(bio)ontology.  The following is from Jim's brochure description:

                                       DINOSAUR EXTINCTION: is the asteroid-impact theory ecologically plausible?
In 1980, the Nobel Prize winning UC Berkeley physicist Luis Alvarez, his geologist son Walter Alvarez, and two nuclear chemist colleagues published the paper titled "Extraterrestrial cause for the Cretaceous-Tertiary extinction"(1980 Science 208:1095) article in which they proposed that an asteroid that struck Earth approximately 64 million years ago was responsible for the extinction of the dinosaurs. Commonly known as the "asteroid impact theory", this idea rapidly gained support among paleontologists and has become part of the accepted widsom regarding the demise of the dinosaurs. For example, TV programs based on the expert advice of prominent paleontologists depict dinosaurs such as Tyrannosaurus rex and Brachiosaurus [note: Jim is using this taxon as a general, relatively familiar example for sauropods vs. mentioning end-Cretaceous taxa probably not known  to non-dinosaur students] either being enveloped in the fireball created by the! ! direct impact of the asteroid or slowly dying due to exposure to nuclear winter-like conditions. Although there is little question about the juxtaposition in geological time of the dinosaur extinction and the world-wide impact of an asteroid collision, no one has provided a plausible explanation of how this extinction might have occurred from an ecological and life history perspective. The theory is effectively one of eradication -- the theory purports to explain how 100% of thousands of different species of dinosaurs went extinct due to the direct and indirect effects of the asteroid -- from the T. rex-sized dinosaurs to small insect- and seed-eating species, from the desert- and forest-dwellers to the savannah- and marsh-inhabitants, from species inhabiting the tropics as well as those in polar regions. The broad purpose of this seminar is to explore whether the asteroid impact theory can stand up to ecological scrutiny. Students will be asked to bring life history t! ! heory and principles of population ecology to bear on the question of how every species of dinosaur could have become extinct worldwide due to this singular event while, at the same time, the extinction rates of other groups ranged from negligible (e.g., frogs, salamanders, placental mammals) to substantial, but far from complete (e.g., 20-70% extinction rates for turtles, marsupials, and ray-finned fishes). In other words, why were the dinosaurs the only broad group to experience complete demise? Or to reframe the question and assume (as do many contemporary paleontologists) that birds are living dinosaurs, why were the progenitors of modern birds the only dinosaurian group to survive the asteroid?
     SEMINAR GOALS
The goals of this seminar are for students to: (1) review critically the existing theories concerning the dinosaur extinction with particular emphasis on the asteroid impact theory; (2) explore the ecological plausibility of this explanation; (3) debate both the merits and the gaps in the asteroid impact theory and propose new explanations; and (4) develop critical thinking about science and hypothesis testing in general but ecology, evolution, and paleontology, in particular.

     Needless to say, the seminar should be fascinating, as Jim is a careful, methodical eco-entomologist, whose continuing research on the subject will result, I think, in a paper of far-reaching consequences. He does not deny the bollide event's effects on North American biozones, and he is not unaware of the paleoclimatic and oceanographic alterations being investigated by David Beerling et al. (rising and fluctuating sea levels > environmental stresses on flowering plants herbivores > meteorological patterns of some degree of ferocity). But, Jim does pose some scientific questions for which ecological answers are sometimes broadly attenuated without the specificity required.