Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California
The Pliocene fossil porpoise SDSNH 65276 has extremely elongate mandibular morphology, unlike that of any marine amniote, and is superficially most similar to the living bird species known as skimmers ( Rynchops sp .). Endocasts of the pterygoid sinuses and endocranial cavity were digitally segmente...
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Online Access: | http://dx.doi.org/10.1666/13-109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000002511 |
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crcambridgeupr:10.1666/13-109 2023-06-11T04:16:01+02:00 Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California Racicot, Rachel A. Rowe, Timothy 2014 http://dx.doi.org/10.1666/13-109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000002511 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Journal of Paleontology volume 88, issue 4, page 652-663 ISSN 0022-3360 1937-2337 Paleontology journal-article 2014 crcambridgeupr https://doi.org/10.1666/13-109 2023-05-01T18:22:33Z The Pliocene fossil porpoise SDSNH 65276 has extremely elongate mandibular morphology, unlike that of any marine amniote, and is superficially most similar to the living bird species known as skimmers ( Rynchops sp .). Endocasts of the pterygoid sinuses and endocranial cavity were digitally segmented from high-resolution X-ray CT scans of the specimen to explore internal anatomy of functionally and phylogenetically important anatomical features of this specimen and odontocetes in general. The sinuses are similar in volume and shape to extant porpoise species, but the dorsal extension of the preorbital lobes are particularly elongate as in the harbor porpoise ( Phocoena phocoena ). The cranial endocast also shows similarities with extant porpoises, but has much deeper interhemispheric fissures, which are filled by ossified meninges, particularly a deep falx cerebri and shallower tentorium cerebelli. Ossifications of these parts of the meninges may reflect faster angular accelerations of the head, deeper diving ability, or both. Penetrations of the endocranial cavity for cranial nerves and blood vessels are like those of extant porpoises. The internal skull morphology of this unique delphinoid sheds additional light both on its phylogenetic affinities and novel odontocete adaptations. Article in Journal/Newspaper Phocoena phocoena Cambridge University Press (via Crossref) Journal of Paleontology 88 4 652 663 |
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Cambridge University Press (via Crossref) |
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English |
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Paleontology |
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Paleontology Racicot, Rachel A. Rowe, Timothy Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
topic_facet |
Paleontology |
description |
The Pliocene fossil porpoise SDSNH 65276 has extremely elongate mandibular morphology, unlike that of any marine amniote, and is superficially most similar to the living bird species known as skimmers ( Rynchops sp .). Endocasts of the pterygoid sinuses and endocranial cavity were digitally segmented from high-resolution X-ray CT scans of the specimen to explore internal anatomy of functionally and phylogenetically important anatomical features of this specimen and odontocetes in general. The sinuses are similar in volume and shape to extant porpoise species, but the dorsal extension of the preorbital lobes are particularly elongate as in the harbor porpoise ( Phocoena phocoena ). The cranial endocast also shows similarities with extant porpoises, but has much deeper interhemispheric fissures, which are filled by ossified meninges, particularly a deep falx cerebri and shallower tentorium cerebelli. Ossifications of these parts of the meninges may reflect faster angular accelerations of the head, deeper diving ability, or both. Penetrations of the endocranial cavity for cranial nerves and blood vessels are like those of extant porpoises. The internal skull morphology of this unique delphinoid sheds additional light both on its phylogenetic affinities and novel odontocete adaptations. |
format |
Article in Journal/Newspaper |
author |
Racicot, Rachel A. Rowe, Timothy |
author_facet |
Racicot, Rachel A. Rowe, Timothy |
author_sort |
Racicot, Rachel A. |
title |
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
title_short |
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
title_full |
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
title_fullStr |
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
title_full_unstemmed |
Endocranial anatomy of a new fossil porpoise (Odontoceti, Phocoenidae) from the Pliocene San Diego Formation of California |
title_sort |
endocranial anatomy of a new fossil porpoise (odontoceti, phocoenidae) from the pliocene san diego formation of california |
publisher |
Cambridge University Press (CUP) |
publishDate |
2014 |
url |
http://dx.doi.org/10.1666/13-109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000002511 |
genre |
Phocoena phocoena |
genre_facet |
Phocoena phocoena |
op_source |
Journal of Paleontology volume 88, issue 4, page 652-663 ISSN 0022-3360 1937-2337 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1666/13-109 |
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Journal of Paleontology |
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88 |
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4 |
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652 |
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663 |
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1768373352105246720 |