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 assess...
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crroyalsociety:10.1098/rsbl.2019.0070 2024-09-15T18:40:20+00:00 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 World Wildlife Fund 2019 http://dx.doi.org/10.1098/rsbl.2019.0070 https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2019.0070 https://royalsocietypublishing.org/doi/full-xml/10.1098/rsbl.2019.0070 en eng The Royal Society https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ Biology Letters volume 15, issue 5, page 20190070 ISSN 1744-9561 1744-957X journal-article 2019 crroyalsociety https://doi.org/10.1098/rsbl.2019.0070 2024-08-12T04:27:43Z 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. Article in Journal/Newspaper Ursus maritimus The Royal Society Biology Letters 15 5 20190070 |
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Open Polar |
collection |
The Royal Society |
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crroyalsociety |
language |
English |
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. |
author2 |
World Wildlife Fund |
format |
Article in Journal/Newspaper |
author |
Folio, Dorinda Marie Aars, Jon Gimenez, Olivier Derocher, Andrew E. Wiig, Øystein Cubaynes, Sarah |
spellingShingle |
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 |
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://dx.doi.org/10.1098/rsbl.2019.0070 https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2019.0070 https://royalsocietypublishing.org/doi/full-xml/10.1098/rsbl.2019.0070 |
genre |
Ursus maritimus |
genre_facet |
Ursus maritimus |
op_source |
Biology Letters volume 15, issue 5, page 20190070 ISSN 1744-9561 1744-957X |
op_rights |
https://royalsociety.org/journals/ethics-policies/data-sharing-mining/ |
op_doi |
https://doi.org/10.1098/rsbl.2019.0070 |
container_title |
Biology Letters |
container_volume |
15 |
container_issue |
5 |
container_start_page |
20190070 |
_version_ |
1810484632469110784 |