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End-Cretaceous squamate extinction worse than thought

From: Ben Creisler

A new online paper:

Nicholas R. Longrich, Bhart-Anjan S. Bhullar, and Jacques A. Gauthier (2012)
Mass extinction of lizards and snakes at the Cretaceous–Paleogene boundary.
Proceedings of the National Academy of Sciences (advance online publication)
doi: 10.1073/pnas.1211526110

The Cretaceous–Paleogene (K-Pg) boundary is marked by a major mass
extinction, yet this event is thought to have had little effect on the
diversity of lizards and snakes (Squamata). A revision of fossil
squamates from the Maastrichtian and Paleocene of North America shows
that lizards and snakes suffered a devastating mass extinction
coinciding with the Chicxulub asteroid impact. Species-level
extinction was 83%, and the K-Pg event resulted in the elimination of
many lizard groups and a dramatic decrease in morphological disparity.
Survival was associated with small body size and perhaps large
geographic range. The recovery was prolonged; diversity did not
approach Cretaceous levels until 10 My after the extinction, and
resulted in a dramatic change in faunal composition. The squamate
fossil record shows that the end-Cretaceous mass extinction was far
more severe than previously believed, and underscores the role played
by mass extinctions in driving diversification.

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