How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears
Life-history theory predicts that females' age and size affect the level of maternal investment in current reproduction, balanced against the future reproductive effort, maintenance and survival. Using long-term (30 years) individual data on 193 female polar bears (Ursus maritimus), we assessed...
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ftpubmed:oai:pubmedcentral.nih.gov:6548740 2023-05-15T18:42:25+02:00 How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears Folio, Dorinda Marie Aars, Jon Gimenez, Olivier Derocher, Andrew E. Wiig, Øystein Cubaynes, Sarah 2019-05 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548740/ http://www.ncbi.nlm.nih.gov/pubmed/31039729 https://doi.org/10.1098/rsbl.2019.0070 en eng The Royal Society http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548740/ http://www.ncbi.nlm.nih.gov/pubmed/31039729 http://dx.doi.org/10.1098/rsbl.2019.0070 © 2019 The Author(s) http://royalsocietypublishing.org/licence Published by the Royal Society. All rights reserved. Evolutionary Biology Text 2019 ftpubmed https://doi.org/10.1098/rsbl.2019.0070 2020-05-03T00:23:32Z Life-history theory predicts that females' age and size affect the level of maternal investment in current reproduction, balanced against the future reproductive effort, maintenance and survival. Using long-term (30 years) individual data on 193 female polar bears (Ursus maritimus), we assessed age- and size-specific variation on litter size. Litter size varied with maternal age, younger females had higher chances of losing a cub during their first months of life. Results suggest an improvement in reproductive abilities early in life due to experience with subsequent reproductive senescence. Litter size increased with maternal size, indicating that size may reflect individual quality. We also found an optimum in the probability of having twins, suggesting stabilizing selection on female body size. Heterogeneity was observed among the largest females, suggesting that large size comes at a cost. Text Ursus maritimus PubMed Central (PMC) Biology Letters 15 5 20190070 |
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Open Polar |
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PubMed Central (PMC) |
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ftpubmed |
language |
English |
topic |
Evolutionary Biology |
spellingShingle |
Evolutionary Biology Folio, Dorinda Marie Aars, Jon Gimenez, Olivier Derocher, Andrew E. Wiig, Øystein Cubaynes, Sarah How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
topic_facet |
Evolutionary Biology |
description |
Life-history theory predicts that females' age and size affect the level of maternal investment in current reproduction, balanced against the future reproductive effort, maintenance and survival. Using long-term (30 years) individual data on 193 female polar bears (Ursus maritimus), we assessed age- and size-specific variation on litter size. Litter size varied with maternal age, younger females had higher chances of losing a cub during their first months of life. Results suggest an improvement in reproductive abilities early in life due to experience with subsequent reproductive senescence. Litter size increased with maternal size, indicating that size may reflect individual quality. We also found an optimum in the probability of having twins, suggesting stabilizing selection on female body size. Heterogeneity was observed among the largest females, suggesting that large size comes at a cost. |
format |
Text |
author |
Folio, Dorinda Marie Aars, Jon Gimenez, Olivier Derocher, Andrew E. Wiig, Øystein Cubaynes, Sarah |
author_facet |
Folio, Dorinda Marie Aars, Jon Gimenez, Olivier Derocher, Andrew E. Wiig, Øystein Cubaynes, Sarah |
author_sort |
Folio, Dorinda Marie |
title |
How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
title_short |
How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
title_full |
How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
title_fullStr |
How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
title_full_unstemmed |
How many cubs can a mum nurse? Maternal age and size influence litter size in polar bears |
title_sort |
how many cubs can a mum nurse? maternal age and size influence litter size in polar bears |
publisher |
The Royal Society |
publishDate |
2019 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548740/ http://www.ncbi.nlm.nih.gov/pubmed/31039729 https://doi.org/10.1098/rsbl.2019.0070 |
genre |
Ursus maritimus |
genre_facet |
Ursus maritimus |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548740/ http://www.ncbi.nlm.nih.gov/pubmed/31039729 http://dx.doi.org/10.1098/rsbl.2019.0070 |
op_rights |
© 2019 The Author(s) http://royalsocietypublishing.org/licence Published by the Royal Society. All rights reserved. |
op_doi |
https://doi.org/10.1098/rsbl.2019.0070 |
container_title |
Biology Letters |
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15 |
container_issue |
5 |
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20190070 |
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1766232075456741376 |