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Phanerozoic diversity and neutral theory

Steven M. Holland and Judith A. Sclafani
Phanerozoic diversity and neutral theory
Paleobiology (June 2015) 41 (3): 369-376


Although Phanerozoic increases in the global richness, local richness, and evenness of marine invertebrates are well documented, a common explanation for these patterns has been difficult to identify. Evidence is presented here from marine invertebrate communities that there is a Phanerozoic increase in the fundamental biodiversity number (theta ), which describes diversity and relative abundance distributions in neutral ecological theory. If marine ecosystems behave according to the rules of Hubbell's Neutral Theory of Biodiversity and Biogeography, the Phanerozoic increase in theta suggests three possible mechanisms for the parallel increases in global richness, local richness, and evenness: (1) an increase in the per-individual probability of speciation, (2) an increase in the area occupied by marine metacommunities, and (3) an increase in the density (per-area abundance) of marine organisms. Because speciation rates have declined over time and because there is no clear evidence for an increase in metacommunity area through the Phanerozoic, the most likely of these is an increase in the spatial density of marine invertebrates over the Phanerozoic, an interpretation supported by previous studies of fossil abundance. This, coupled with a Phanerozoic rise in body size, suggests that an increase in primary productivity through time is the primary cause of Phanerozoic increases in theta , global richness, local richness, local evenness, abundance, and body size.

ISSN: 0094-8373
EISSN: 1938-5331
Serial Title: Paleobiology
Serial Volume: 41
Serial Issue: 3
Title: Phanerozoic diversity and neutral theory
Affiliation: University of Georgia, Department of Geology, Athens, GA, United States
Pages: 369-376
Published: 201506
Text Language: English
Publisher: Paleontological Society, Lawrence, KS, United States
References: 47
Accession Number: 2016-003467
Categories: Invertebrate paleontology
Document Type: Serial
Bibliographic Level: Analytic
Annotation: NSF Grant EAR-0948895
Illustration Description: illus. incl. 1 table
Source Note: Online First
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, The Paleontological Society. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201602
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