Mosasaur evolution drivers

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com

A new online paper:

Michael J. Polcyn, Louis L. Jacobs, Ricardo Araújo, Anne S. Schulp &
Octávio Mateus (2013)
Physical Drivers of Mosasaur Evolution.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)
doi: http://dx.doi.org/10.1016/j.palaeo.2013.05.018
http://www.sciencedirect.com/science/article/pii/S0031018213002514


Mosasaurs are marine squamates with a 32.5 million-year history from
their appearance at 98 Ma to their extinction at the K-Pg boundary
(65.5 Ma). Using a database of 43 generic and 94 species-level taxa,
we compare the taxonomic diversity and patterns of morphological
disparity in mosasaurs with sea level, sea surface temperature, and
stable carbon isotope curves for the Upper Cretaceous to explore
factors that may have influenced their evolution. No single factor
unambiguously accounts for all radiations, diversification, and
extinctions; however, the broader patterns of taxonomic
diversification and morphological disparity point to niche
differentiation in a “fishing up” scenario under the influence of
“bottom-up” selective pressures. The most likely driving force in
mosasaur evolution was high productivity in the Late Cretaceous,
driven by tectonically controlled sea levels and climatically
controlled ocean stratification and nutrient delivery. When
productivity collapsed at the end of the Cretaceous, coincident with
bolide impact, mosasaurs became extinct.