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: | Text |
Language: | English |
Published: |
Public Library of Science
2015
|
Subjects: | |
Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526471/ http://www.ncbi.nlm.nih.gov/pubmed/26244784 https://doi.org/10.1371/journal.pone.0131856 |
id |
ftpubmed:oai:pubmedcentral.nih.gov:4526471 |
---|---|
record_format |
openpolar |
spelling |
ftpubmed:oai:pubmedcentral.nih.gov:4526471 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 2015-08-05 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526471/ http://www.ncbi.nlm.nih.gov/pubmed/26244784 https://doi.org/10.1371/journal.pone.0131856 en eng Public Library of Science http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526471/ http://www.ncbi.nlm.nih.gov/pubmed/26244784 http://dx.doi.org/10.1371/journal.pone.0131856 http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited CC-BY Research Article Text 2015 ftpubmed https://doi.org/10.1371/journal.pone.0131856 2015-08-16T00:06:28Z 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. et sp. 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. Text Odobenus rosmarus walrus* PubMed Central (PMC) Pacific PLOS ONE 10 8 e0131856 |
institution |
Open Polar |
collection |
PubMed Central (PMC) |
op_collection_id |
ftpubmed |
language |
English |
topic |
Research Article |
spellingShingle |
Research Article Tanaka, Yoshihiro Kohno, Naoki A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids |
topic_facet |
Research Article |
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. et sp. 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 |
Text |
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 |
publishDate |
2015 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526471/ http://www.ncbi.nlm.nih.gov/pubmed/26244784 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://www.ncbi.nlm.nih.gov/pmc/articles/PMC4526471/ http://www.ncbi.nlm.nih.gov/pubmed/26244784 http://dx.doi.org/10.1371/journal.pone.0131856 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited |
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_ |
1766159828564049920 |