Tectonic influence on Cenozoic mammal richness and sedimentation history of the Basin and Range, western North America

Katharine M Loughney; Catherine Badgley; Alireza Bahadori; William E Holt; E Troy Rasbury

doi:10.1126/sciadv.abh4470

Tectonic influence on Cenozoic mammal richness and sedimentation history of the Basin and Range, western North America

Sci Adv. 2021 Nov 5;7(45):eabh4470. doi: 10.1126/sciadv.abh4470. Epub 2021 Nov 3.

Authors

Katharine M Loughney^{1

2}, Catherine Badgley¹, Alireza Bahadori³, William E Holt³, E Troy Rasbury³

Affiliations

¹ Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.
² Department of Geology, University of Georgia, Athens, GA 30602, USA.
³ Department of Geosciences, Stony Brook University, Stony Brook, NY 11794, USA.

Abstract

Tectonic activity can drive speciation and sedimentation, potentially causing the fossil and rock records to share common patterns through time. The Basin and Range of western North America arose through widespread extension and collapse of topographic highlands in the Miocene, creating numerous basins with rich mammalian fossil records. We analyzed patterns of mammalian species richness from 36 to 0 million years ago in relation to the history of sediment accumulation to test whether intervals of high species richness corresponded with elevated sediment accumulation and fossil burial in response to tectonic deformation. We found that the sedimentary record of the Basin and Range tracks the tectonic evolution of landscapes, whereas species-richness trends reflect actual increased richness in the Miocene rather than increased fossil burial. The sedimentary record of the region broadly determines the preservation of the fossil record but does not drive the Miocene peak in mammalian species richness.