A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids
The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8-2...
Published in: | PLOS ONE |
---|---|
Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Public Library of Science
|
Subjects: | |
Online Access: | http://hdl.handle.net/2115/60359 https://doi.org/10.1371/journal.pone.0131856 |
id |
fthokunivhus:oai:eprints.lib.hokudai.ac.jp:2115/60359 |
---|---|
record_format |
openpolar |
spelling |
fthokunivhus:oai:eprints.lib.hokudai.ac.jp:2115/60359 2023-05-15T17:52:25+02:00 A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids Tanaka, Yoshihiro Kohno, Naoki http://hdl.handle.net/2115/60359 https://doi.org/10.1371/journal.pone.0131856 eng eng Public Library of Science http://hdl.handle.net/2115/60360 http://hdl.handle.net/2115/60359 PLOS ONE, 10(8): e0131856 http://dx.doi.org/10.1371/journal.pone.0131856 http://creativecommons.org/licenses/by/4.0/ CC-BY 457 article fthokunivhus https://doi.org/10.1371/journal.pone.0131856 2022-11-18T01:03:36Z The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8-2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen.etsp.nov. from the late Miocene (ca. 10.0-9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses. Archaeodobenus akamatsui is the contemporaneous Pseudotaria muramotoi from the same formation, but they are distinguishable from each other in size and shape of the occipital condyle, foramen magnum and mastoid process of the cranium, and other postcranial features. Based on our phylogenetic analysis, A. akamatsui might have split from P. muramotoi at the late Miocene in the western North Pacific. This rapid diversification of the archaic odobenids occurred with a combination of marine regression and transgression, which provided geological isolation among the common ancestors of extinct odobenids. Article in Journal/Newspaper Odobenus rosmarus walrus* Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) Pacific PLOS ONE 10 8 e0131856 |
institution |
Open Polar |
collection |
Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) |
op_collection_id |
fthokunivhus |
language |
English |
topic |
457 |
spellingShingle |
457 Tanaka, Yoshihiro Kohno, Naoki A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
topic_facet |
457 |
description |
The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8-2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen.etsp.nov. from the late Miocene (ca. 10.0-9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses. Archaeodobenus akamatsui is the contemporaneous Pseudotaria muramotoi from the same formation, but they are distinguishable from each other in size and shape of the occipital condyle, foramen magnum and mastoid process of the cranium, and other postcranial features. Based on our phylogenetic analysis, A. akamatsui might have split from P. muramotoi at the late Miocene in the western North Pacific. This rapid diversification of the archaic odobenids occurred with a combination of marine regression and transgression, which provided geological isolation among the common ancestors of extinct odobenids. |
format |
Article in Journal/Newspaper |
author |
Tanaka, Yoshihiro Kohno, Naoki |
author_facet |
Tanaka, Yoshihiro Kohno, Naoki |
author_sort |
Tanaka, Yoshihiro |
title |
A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
title_short |
A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
title_full |
A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
title_fullStr |
A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
title_full_unstemmed |
A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
title_sort |
new late miocene odobenid (mammalia: carnivora) from hokkaido, japan suggests rapid diversification of basal miocene odobenids |
publisher |
Public Library of Science |
url |
http://hdl.handle.net/2115/60359 https://doi.org/10.1371/journal.pone.0131856 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Odobenus rosmarus walrus* |
genre_facet |
Odobenus rosmarus walrus* |
op_relation |
http://hdl.handle.net/2115/60360 http://hdl.handle.net/2115/60359 PLOS ONE, 10(8): e0131856 http://dx.doi.org/10.1371/journal.pone.0131856 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1371/journal.pone.0131856 |
container_title |
PLOS ONE |
container_volume |
10 |
container_issue |
8 |
container_start_page |
e0131856 |
_version_ |
1766159825329192960 |