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The Paleozoic Era was host to many significant biotic events such as the Great Ordovician Biodiversification Event, the Late Ordovician Mass Extinction, and the Late Devonian extinctions. These events were likely catalyzed by abiotic (e.g. climate) versus biotic drivers. Echinoderms are globally distributed, temporally expansive, and easily identifiable; these qualities make them an excellent model system to test hypotheses relating biodiversity with abiotic factors. Biodiversity patterns of echinoderms are currently not well understood because of a lack of focus on the dynamics of the entire clade. To remedy this, we have worked to expand current understandings of Paleozoic echinoderm diversity patterns by investigating the global distribution and temporal occurrences of taxa spanning the entire clade. Results suggest patterns of diversity unique to previously established trends that predominantly centered on a limited number of echinoderm groups. To examine the connection between climate change and Paleozoic echinoderm biodiversity (i.e., diversification, extinction, and origination rates), we collated stable oxygen isotope data from the primary literature spanning the Ordovician to the Devonian. We compiled these data to create a continuous curve of δO values during the described period to better evaluate in tandem with echinoderm diversity metrics. When the δO curve is compared to the echinoderm biodiversity patterns, we found that cooling periods coincide with increased extinction rates, corroborating prior hypotheses that major end-Ordovician cooling triggered changes in echinoderm biodiversity at a global level and further identifying a potential pattern in abiotic drivers in echinoderm biodiversity. The connection between Paleozoic echinoderm biodiversity and other abiotic factors will be further studied by comparing these recovered patterns with paleolatitudinal distributions.
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Perfect storms shape biodiversity in time and space
Abstract Many of the most dramatic patterns in biological diversity are created by “Perfect Storms” —rare combinations of mutually reinforcing factors that push origination, extinction, or diversity accommodation to extremes. These patterns include the strongest diversification events (e.g. the Cambrian Explosion of animal body plans), the proliferation of hyperdiverse clades (e.g. insects, angiosperms), the richest biodiversity hotspots (e.g. the New World Tropical Montane regions and the ocean's greatest diversity pump, the tropical West Pacific), and the most severe extinction events (e.g. the Big Five mass extinctions of the Phanerozoic). Human impacts on the modern biota are also a Perfect Storm, and both mitigation and restoration strategies should be framed accordingly, drawing on biodiversity's responses to multi-driver processes in the geologic past. This approach necessarily weighs contributing factors, identifying their often non-linear and time-dependent interactions, instead of searching for unitary causes.
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- Award ID(s):
- 2049627
- PAR ID:
- 10467973
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Evolutionary Journal of the Linnean Society
- Volume:
- 2
- Issue:
- 1
- ISSN:
- 2752-938X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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