Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Were bivalves ecologically dominant over brachiopods in the late Paleozoic? A test using exceptionally preserved fossil assemblages

Shannon Hsieh, Andrew M. Bush and J. Bret Bennington
Were bivalves ecologically dominant over brachiopods in the late Paleozoic? A test using exceptionally preserved fossil assemblages
Paleobiology (May 2019) 45 (2): 265-279

Abstract

Interpreting changes in ecosystem structure from the fossil record can be challenging. In a prominent example, the traditional view that brachiopods were ecologically dominant over bivalves in the Paleozoic has been disputed on both taphonomic and metabolic grounds. Aragonitic bivalves may be underrepresented in many fossil assemblages due to preferential dissolution. Abundance counts may further understate the ecological importance of bivalves, which tend to have more biomass and higher metabolic rates than brachiopods. We evaluate the relative importance of the two clades in exceptionally preserved, bulk-sampled fossil assemblages from the Pennsylvanian Breathitt Formation of Kentucky, where aragonitic bivalves are preserved as shells, not molds. At the regional scale, brachiopods were twice as abundant as bivalves and were collectively equivalent in biomass and energy use. Analyses of samples from the Paleobiology Database that contain abundance counts are consistent with these results and show no clear trend in the relative ecological importance of bivalves during the middle and late Paleozoic. Bivalves were probably more important in Paleozoic ecosystems than is apparent in many fossil assemblages, but they were not clearly dominant over brachiopods until after the Permian-Triassic extinction, which caused the shelly benthos to shift from bivalve and brachiopod dominated to merely bivalve dominated.


ISSN: 0094-8373
EISSN: 1938-5331
Coden: PALBBM
Serial Title: Paleobiology
Serial Volume: 45
Serial Issue: 2
Title: Were bivalves ecologically dominant over brachiopods in the late Paleozoic? A test using exceptionally preserved fossil assemblages
Affiliation: University of Connecticut, Department of Ecology and Evolutionary Biology, Storrs, CT, United States
Pages: 265-279
Published: 201905
Text Language: English
Publisher: Paleontological Society, Lawrence, KS, United States
References: 76
Accession Number: 2019-062059
Categories: Invertebrate paleontology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sketch map
N36°45'00" - N38°00'00", W83°30'00" - W81°30'00"
Secondary Affiliation: Hofstra University, USA, United States
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2019, American Geosciences Institute. Abstract, Copyright, The Paleontological Society. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201932
Close Modal

or Create an Account

Close Modal
Close Modal