Scale-dependence of Cope's rule in body size evolution of Paleozoic brachiopods.

ABSTRACT: The average body size of brachiopods from a single habitat type increased gradually by more than two orders of magnitude during their initial Cambrian-Devonian radiation. This increase occurred nearly in parallel across all major brachiopod clades (classes and orders) and is consistent with Cope's rule: the tendency for size to increase over geological time. The increase is not observed within small, constituent clades (represented here by families), which underwent random, unbiased size changes. This scale-dependence is caused by the preferential origination of new families possessing initially larger body sizes. However, this increased family body size does not confer advantages in terms of greater geological duration or genus richness over families possessing smaller body sizes. We sugg

SUBMITTER: Novack-Gottshall PM 

PROVIDER: S-EPMC2291137 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature