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Re: Re: "No Bolides!"
> What do people think about the Pleistocene extinctions in North
>America? They seem comparable to the Late Cretaceous. We've lost wooly
>mammoths, sabertooths, dire wolves, teratorns, lions, giant lions,
>horses, ground sloths, phorusrhacids, cheetahs, rhinos, those dog-bear
>things, and plenty of other animals. As for niches not refilled, we've lost
>large grazers like mammoths, rearing browsers like sloths, big-game
>predators like sabertooths, etc. etc. The Late Cretaceous saw groups like
>Centrosaurines on the way out, but we did lose elephants, rhinos, etc.,
>so it was not merely at the generic level.
[The mid-Maastrichtian extinction of the centrosaurines was global as well
as regional, since this taxon was restricted to western North America.
Proboscideans and rhinoceratids, however, experienced a regional extirpation
in the New World, but presist to this day.]
More importantly, the Pleistocene-Holocene extinctions are very different
from most (all) previous mass extinctions because we have not lost major
clades of marine invertebrates.
Thomas R. Holtz, Jr.
Vertebrate Paleontologist Webpage: http://www.geol.umd.edu
Dept. of Geology Email:firstname.lastname@example.org
University of Maryland Phone:301-405-4084
College Park, MD 20742 Fax: 301-314-9661