Evenness of Cambrian-Ordovician benthic marine communities in North America

From: Paleobiology | Date: July 1, 2004| Author: | Copyright information

Abstract.-Biodiversity has two principal components: richness (the number of taxa) and evenness (the distribution of individuals among taxa). Both of these attributes are critical in defining community composition and structure, but evenness may be particularly important for ecological reasons, e specially in the context of a possible evolutionary increase in richness. Here I examine abundance data in well-preserved Cambrian and Ordovician benthic marine assemblages from mixed carbonate-shale and shale lithofacies deposited below normal wave base in North America. Evenness increases ...

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