Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota
Many explanations for Eocene climate change focus on the Southern Ocean—where tectonics influenced oceanic gateways, ocean circulation reduced heat transport, and greenhouse gas declines prompted glaciation. To date, few studies focus on marine vertebrates at high latitudes to discern paleoecologica...
Published in: | Paleoceanography and Paleoclimatology |
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Language: | English |
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Enheten för paleobiologi
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Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-3975 https://doi.org/10.1029/2020PA003997 |
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ftnrm:oai:DiVA.org:nrm-3975 2023-05-15T16:02:30+02:00 Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota Kim, Sora Zeichner, Sarah Colman, Albert Scher, Howie KRIWET, JÜRGEN Mörs, Thomas Huber, Matthew 2020 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-3975 https://doi.org/10.1029/2020PA003997 eng eng Enheten för paleobiologi Department of Life and Environmental Sciences, University of California, Merced, CA, USA Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA Department of Earth, Environment, and Planetary Sciences, Rice University, Houston, TX, USA Department of Earth, Ocean, and Environment, University of South Carolina, Columbia, SC, USA Department of Paleontology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria. Department of Earth, Atmosphere, and Planetary Sciences, Purdue University, West Lafayette, IN, USA Paleoceanography and Paleoclimatology, 2572-4517, 2020, 35:12, http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-3975 doi:10.1029/2020PA003997 info:eu-repo/semantics/openAccess Neodymium isotope analysis oxygen isotope analysis paleobiology paleoclimate Seymour Island Temperature Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap Article in journal info:eu-repo/semantics/article text 2020 ftnrm https://doi.org/10.1029/2020PA003997 2021-10-08T07:21:22Z Many explanations for Eocene climate change focus on the Southern Ocean—where tectonics influenced oceanic gateways, ocean circulation reduced heat transport, and greenhouse gas declines prompted glaciation. To date, few studies focus on marine vertebrates at high latitudes to discern paleoecological and paleoenvironmental impacts of this climate transition. The Tertiary Eocene La Meseta (TELM) Formation has a rich fossil assemblage to characterize these impacts; Striatolamia macrota, an extinct (†) sand tiger shark, is abundant throughout the La Meseta Formation. Body size is often tracked to characterize and integrate across multiple ecological dimensions. †S. macrota body size distributions indicate limited changes during TELMs 2–5 based on anterior tooth crown height (n = 450, mean = 19.6 ± 6.4 mm). Similarly, environmental conditions remained stable through this period based on δ18OPO4 values from tooth enameloid (n = 42; 21.5 ± 1.6‰), which corresponds to a mean temperature of 22.0 ± 4.0°C. Our preliminary εNd (n = 4) results indicate an early Drake Passage opening with Pacific inputs during TELM 2–3 (45–43 Ma) based on single unit variation with an overall radiogenic trend. Two possible hypotheses to explain these observations are (1) †S. macrota modified its migration behavior to ameliorate environmental changes related to the Drake Passage opening, or (2) the local climate change was small and gateway opening had little impact. While we cannot rule out an ecological explanation, a comparison with climate model results suggests that increased CO2 produces warm conditions that also parsimoniously explain the observations. Article in Journal/Newspaper Drake Passage Seymour Island Southern Ocean Swedish Museum of Natural History: Publications (DiVA) Drake Passage Pacific Seymour ENVELOPE(-56.767,-56.767,-64.283,-64.283) Seymour Island ENVELOPE(-56.750,-56.750,-64.283,-64.283) Southern Ocean Paleoceanography and Paleoclimatology 35 12 |
institution |
Open Polar |
collection |
Swedish Museum of Natural History: Publications (DiVA) |
op_collection_id |
ftnrm |
language |
English |
topic |
Neodymium isotope analysis oxygen isotope analysis paleobiology paleoclimate Seymour Island Temperature Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap |
spellingShingle |
Neodymium isotope analysis oxygen isotope analysis paleobiology paleoclimate Seymour Island Temperature Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap Kim, Sora Zeichner, Sarah Colman, Albert Scher, Howie KRIWET, JÜRGEN Mörs, Thomas Huber, Matthew Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
topic_facet |
Neodymium isotope analysis oxygen isotope analysis paleobiology paleoclimate Seymour Island Temperature Other Earth and Related Environmental Sciences Annan geovetenskap och miljövetenskap |
description |
Many explanations for Eocene climate change focus on the Southern Ocean—where tectonics influenced oceanic gateways, ocean circulation reduced heat transport, and greenhouse gas declines prompted glaciation. To date, few studies focus on marine vertebrates at high latitudes to discern paleoecological and paleoenvironmental impacts of this climate transition. The Tertiary Eocene La Meseta (TELM) Formation has a rich fossil assemblage to characterize these impacts; Striatolamia macrota, an extinct (†) sand tiger shark, is abundant throughout the La Meseta Formation. Body size is often tracked to characterize and integrate across multiple ecological dimensions. †S. macrota body size distributions indicate limited changes during TELMs 2–5 based on anterior tooth crown height (n = 450, mean = 19.6 ± 6.4 mm). Similarly, environmental conditions remained stable through this period based on δ18OPO4 values from tooth enameloid (n = 42; 21.5 ± 1.6‰), which corresponds to a mean temperature of 22.0 ± 4.0°C. Our preliminary εNd (n = 4) results indicate an early Drake Passage opening with Pacific inputs during TELM 2–3 (45–43 Ma) based on single unit variation with an overall radiogenic trend. Two possible hypotheses to explain these observations are (1) †S. macrota modified its migration behavior to ameliorate environmental changes related to the Drake Passage opening, or (2) the local climate change was small and gateway opening had little impact. While we cannot rule out an ecological explanation, a comparison with climate model results suggests that increased CO2 produces warm conditions that also parsimoniously explain the observations. |
format |
Article in Journal/Newspaper |
author |
Kim, Sora Zeichner, Sarah Colman, Albert Scher, Howie KRIWET, JÜRGEN Mörs, Thomas Huber, Matthew |
author_facet |
Kim, Sora Zeichner, Sarah Colman, Albert Scher, Howie KRIWET, JÜRGEN Mörs, Thomas Huber, Matthew |
author_sort |
Kim, Sora |
title |
Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
title_short |
Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
title_full |
Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
title_fullStr |
Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
title_full_unstemmed |
Probing the ecology and climate of the Eocene Southern Ocean with sand tiger sharks Striatolamia macrota |
title_sort |
probing the ecology and climate of the eocene southern ocean with sand tiger sharks striatolamia macrota |
publisher |
Enheten för paleobiologi |
publishDate |
2020 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-3975 https://doi.org/10.1029/2020PA003997 |
long_lat |
ENVELOPE(-56.767,-56.767,-64.283,-64.283) ENVELOPE(-56.750,-56.750,-64.283,-64.283) |
geographic |
Drake Passage Pacific Seymour Seymour Island Southern Ocean |
geographic_facet |
Drake Passage Pacific Seymour Seymour Island Southern Ocean |
genre |
Drake Passage Seymour Island Southern Ocean |
genre_facet |
Drake Passage Seymour Island Southern Ocean |
op_relation |
Paleoceanography and Paleoclimatology, 2572-4517, 2020, 35:12, http://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-3975 doi:10.1029/2020PA003997 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2020PA003997 |
container_title |
Paleoceanography and Paleoclimatology |
container_volume |
35 |
container_issue |
12 |
_version_ |
1766398160846979072 |