Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size
In mammals, males generally are larger than females, though such sexual-size differences have been documented primarily in adults and are relatively poorly known in early life. We studied sexual-size differences in pups of the northern elephant seal (Mirounga angustirostris (Gill, 1866)), which in a...
Published in: | Canadian Journal of Zoology |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
2019
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/pdf/10.1139/cjz-2018-0220 |
id |
crcansciencepubl:10.1139/cjz-2018-0220 |
---|---|
record_format |
openpolar |
spelling |
crcansciencepubl:10.1139/cjz-2018-0220 2023-12-17T10:29:38+01:00 Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size Salogni, E. Galimberti, F. Sanvito, S. Miller, E.H. 2019 http://dx.doi.org/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/pdf/10.1139/cjz-2018-0220 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Zoology volume 97, issue 3, page 241-250 ISSN 0008-4301 1480-3283 Animal Science and Zoology Ecology, Evolution, Behavior and Systematics journal-article 2019 crcansciencepubl https://doi.org/10.1139/cjz-2018-0220 2023-11-19T13:39:35Z In mammals, males generally are larger than females, though such sexual-size differences have been documented primarily in adults and are relatively poorly known in early life. We studied sexual-size differences in pups of the northern elephant seal (Mirounga angustirostris (Gill, 1866)), which in adulthood is one of the most sexually dimorphic mammals. We studied body size at birth and weaning, at Islas San Benito, Mexico, at the southernmost limit of the species’ breeding range. Males were 10% heavier and 2% longer than females at birth. Sexes did not differ significantly in either measure of body size at weaning, although males were slightly heavier (4%) and longer (1%) than females. Neither growth rate nor suckling duration differed between the sexes. In previous studies in California, USA, pups at weaning were heavier than in our study, and males were heavier than females. These differences may reflect ecological, temporal, or life-history differences across populations. The modest difference in sexual-size dimorphism early in life in this species compared with the great difference in adulthood likely reflects multiple selective forces, including constraints on neonatal size set by body size of females, and the weakness of sexual selection at that stage of life. Article in Journal/Newspaper Elephant Seal Canadian Science Publishing (via Crossref) Canadian Journal of Zoology 97 3 241 250 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics |
spellingShingle |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics Salogni, E. Galimberti, F. Sanvito, S. Miller, E.H. Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
topic_facet |
Animal Science and Zoology Ecology, Evolution, Behavior and Systematics |
description |
In mammals, males generally are larger than females, though such sexual-size differences have been documented primarily in adults and are relatively poorly known in early life. We studied sexual-size differences in pups of the northern elephant seal (Mirounga angustirostris (Gill, 1866)), which in adulthood is one of the most sexually dimorphic mammals. We studied body size at birth and weaning, at Islas San Benito, Mexico, at the southernmost limit of the species’ breeding range. Males were 10% heavier and 2% longer than females at birth. Sexes did not differ significantly in either measure of body size at weaning, although males were slightly heavier (4%) and longer (1%) than females. Neither growth rate nor suckling duration differed between the sexes. In previous studies in California, USA, pups at weaning were heavier than in our study, and males were heavier than females. These differences may reflect ecological, temporal, or life-history differences across populations. The modest difference in sexual-size dimorphism early in life in this species compared with the great difference in adulthood likely reflects multiple selective forces, including constraints on neonatal size set by body size of females, and the weakness of sexual selection at that stage of life. |
format |
Article in Journal/Newspaper |
author |
Salogni, E. Galimberti, F. Sanvito, S. Miller, E.H. |
author_facet |
Salogni, E. Galimberti, F. Sanvito, S. Miller, E.H. |
author_sort |
Salogni, E. |
title |
Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
title_short |
Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
title_full |
Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
title_fullStr |
Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
title_full_unstemmed |
Male and female pups of the highly sexually dimorphic northern elephant seal ( Mirounga angustirostris ) differ slightly in body size |
title_sort |
male and female pups of the highly sexually dimorphic northern elephant seal ( mirounga angustirostris ) differ slightly in body size |
publisher |
Canadian Science Publishing |
publishDate |
2019 |
url |
http://dx.doi.org/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjz-2018-0220 http://www.nrcresearchpress.com/doi/pdf/10.1139/cjz-2018-0220 |
genre |
Elephant Seal |
genre_facet |
Elephant Seal |
op_source |
Canadian Journal of Zoology volume 97, issue 3, page 241-250 ISSN 0008-4301 1480-3283 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/cjz-2018-0220 |
container_title |
Canadian Journal of Zoology |
container_volume |
97 |
container_issue |
3 |
container_start_page |
241 |
op_container_end_page |
250 |
_version_ |
1785582062439235584 |