Intraspecific allometry of neonatal size in the Antarctic fur sea (Arctocephalus galapagoensis)
Intraspecific allometry of pup mass as a function of maternal mass was analysed in Antarctic fur seals (Arctocephalus gazella), a highly dimorphic species. The allometric exponent was 0.6, much lower than in interspecific comparisons. Slopes were the same for mother-son pairs as for mother-daughter...
Published in: | Behavioral Ecology and Sociobiology |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Springer
1988
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Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/521544/ https://link.springer.com/article/10.1007%2FBF00295105 |
Summary: | Intraspecific allometry of pup mass as a function of maternal mass was analysed in Antarctic fur seals (Arctocephalus gazella), a highly dimorphic species. The allometric exponent was 0.6, much lower than in interspecific comparisons. Slopes were the same for mother-son pairs as for mother-daughter pairs, but adjusted means were significantly higher for the former, indicating higher reproductive effort of mothers of sons. The correlation of maternal mass with pup mass explained 59% of the variance in female pup mas but only 18% of that in male pup mass. Females appeared to produce sons which were as big as possible. Relative pup mass decreased with increasing maternal mass indicating a lower reproductive effort of bigger and presumably older mothers, contrary to expectations from life history theory. Sex ratio of pups showed no relation to maternal mass. |
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