[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
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)
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.