Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism
The primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or AS...
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| Format: | Article |
| Language: | English |
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The Royal Society
2023-11-01
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| Series: | Royal Society Open Science |
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| Online Access: | https://royalsocietypublishing.org/doi/10.1098/rsos.231443 |
| _version_ | 1797360986894630912 |
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| author | Aureo Banhos Tânia Margarete Sanaiotti Renan Coser Waleska Gravena Francisca Helena Aguiar-Silva Mylena Kaizer Tomas Hrbek Izeni Pires Farias |
| author_facet | Aureo Banhos Tânia Margarete Sanaiotti Renan Coser Waleska Gravena Francisca Helena Aguiar-Silva Mylena Kaizer Tomas Hrbek Izeni Pires Farias |
| author_sort | Aureo Banhos |
| collection | DOAJ |
| description | The primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or ASR towards males. The Harpy Eagle is the world's largest eagle exhibiting RSD. This species is found in the Neotropical region and is currently threatened with extinction. We used molecular markers to determine the sex of 309 Harpy Eagles spanning different life stages—eaglets, subadults and adults—from 1904 to 2021 within the Amazon Rainforest and Atlantic Forest. Sex ratios for all life stages revealed a female-biased deviation across all periods and regions. Our results suggest that the population bias towards females is an evolutionary ecological pattern of this species, and SSR and ASR likely emerged from the PSR. This natural bias towards females may be compensated by an earlier sexual maturation age of males, implying a longer reproductive lifespan and a higher proportion of sexually active males. A better understanding of the Harpy Eagle's life history can contribute to understanding sex-role evolution and enable more appropriate conservation strategies for the species. |
| first_indexed | 2024-03-08T15:47:29Z |
| format | Article |
| id | doaj.art-28739def967f4e17ab9221673feabee4 |
| institution | Directory Open Access Journal |
| issn | 2054-5703 |
| language | English |
| last_indexed | 2024-03-08T15:47:29Z |
| publishDate | 2023-11-01 |
| publisher | The Royal Society |
| record_format | Article |
| series | Royal Society Open Science |
| spelling | doaj.art-28739def967f4e17ab9221673feabee42024-01-09T09:26:53ZengThe Royal SocietyRoyal Society Open Science2054-57032023-11-01101110.1098/rsos.231443Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphismAureo Banhos0Tânia Margarete Sanaiotti1Renan Coser2Waleska Gravena3Francisca Helena Aguiar-Silva4Mylena Kaizer5Tomas Hrbek6Izeni Pires Farias7Departamento de Biologia, Centro de Ciências Exatas, Naturais e da Saúde, Universidade Federal do Espírito Santo - UFES, Alto Universitário, s/n°, Guararema, 29500-000 Alegre, Espírito Santo, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilLaboratório de Evolução e Genética Animal - LEGAL, Universidade Federal do Amazonas - UFAM, Av. General Rodrigo Octavio Jordão Ramos, 6200 - Coroado I, 69080-900 Manaus, Amazonas, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilProjeto Harpia (Harpy Eagle Project - Brazil), Instituto Nacional de Pesquisas da Amazônia – INPA, Av. André Araújo, 2936, Aleixo, 69067-375 Manaus, Amazonas, BrazilThe primary (PSR), secondary (SSR) and adult (ASR) sex ratios of sexually reproducing organisms influence their life histories. Species exhibiting reversed sexual size dimorphism (RSD) may imply a higher cost of female production or lower female survival, thus generating biases in PSR, SSR and/or ASR towards males. The Harpy Eagle is the world's largest eagle exhibiting RSD. This species is found in the Neotropical region and is currently threatened with extinction. We used molecular markers to determine the sex of 309 Harpy Eagles spanning different life stages—eaglets, subadults and adults—from 1904 to 2021 within the Amazon Rainforest and Atlantic Forest. Sex ratios for all life stages revealed a female-biased deviation across all periods and regions. Our results suggest that the population bias towards females is an evolutionary ecological pattern of this species, and SSR and ASR likely emerged from the PSR. This natural bias towards females may be compensated by an earlier sexual maturation age of males, implying a longer reproductive lifespan and a higher proportion of sexually active males. A better understanding of the Harpy Eagle's life history can contribute to understanding sex-role evolution and enable more appropriate conservation strategies for the species.https://royalsocietypublishing.org/doi/10.1098/rsos.231443evolutionFisher's principlelife historymolecular sexingsex allocationsex roles |
| spellingShingle | Aureo Banhos Tânia Margarete Sanaiotti Renan Coser Waleska Gravena Francisca Helena Aguiar-Silva Mylena Kaizer Tomas Hrbek Izeni Pires Farias Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism Royal Society Open Science evolution Fisher's principle life history molecular sexing sex allocation sex roles |
| title | Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism |
| title_full | Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism |
| title_fullStr | Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism |
| title_full_unstemmed | Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism |
| title_short | Long-term female bias in sex ratios across life stages of Harpy Eagle, a large raptor exhibiting reverse sexual size dimorphism |
| title_sort | long term female bias in sex ratios across life stages of harpy eagle a large raptor exhibiting reverse sexual size dimorphism |
| topic | evolution Fisher's principle life history molecular sexing sex allocation sex roles |
| url | https://royalsocietypublishing.org/doi/10.1098/rsos.231443 |
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