Monday, April 26, 2010

Did Dinosaurs and Plants Evolve Together?

Testing coevolutionary hypotheses over geological timescales: interactions between Cretaceous dinosaurs and plants. 2010. R. J. Butler, et al. Biol. J. Linn Soc. 100: 1-15.


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Dinos made from 50,000 flowers during Lalbagh flower show
Abstract [edit]: Distributional data for Cretaceous dinosaur and plant groups were mapped onto palaeogeographical reconstructions in a series of time-slices. Within each time-slice, palaeocontinental surfaces were divided into a series of grids, each of which was scored as present, absent or inapplicable (unsampled) for each group. Distributions were compared statistically to determine whether the putative coevolving groups co-occurred within grid squares more or less frequently than expected by chance.

Pairwise comparisons were made between herbivorous dinosaur clades and major plant groups (e.g. cycads, angiosperms) on a global scale. Only three nonrepeated associations of marginal significance were recovered, demonstrating that, in general, current knowledge of the spatiotemporal distributions of these groups provides little support for coevolutionary hypotheses.