Abundance Distributions Imply Elevated Complexity of Post-Paleozoic Marine Ecosystems.
Wagner, Peter J. 1*; Kosnik, Matthew A. 2; Lidgard, Scott 1
[Report] Science. 314(5803):1289-1292, November 24, 2006.

(Format: HTML)

Likelihood analyses of 1176 fossil assemblages of marine organisms from Phanerozoic (i.e., Cambrian to Recent) assemblages indicate a shift in typical relative-abundance distributions after the Paleozoic. Ecological theory associated with these abundance distributions implies that complex ecosystems are far more common among Meso-Cenozoic assemblages than among the Paleozoic assemblages that preceded them. This transition coincides not with any major change in the way fossils are preserved or collected but with a shift from communities dominated by sessile epifaunal suspension feeders to communities with elevated diversities of mobile and infaunal taxa. This suggests that the end-Permian extinction permanently altered prevailing marine ecosystem structure and precipitated high levels of ecological complexity and alpha diversity in the Meso-Cenozoic.

Copyright (C) 2006 by the American Association for the Advancement of Science