1
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Harvey Sky N, Britnell J, Antwis R, Kartzinel T, Rubenstein D, Toye P, Karani B, Njeru R, Hinchcliffe D, Gaymer J, Mutisya S, Shultz S. Linking diet switching to reproductive performance across populations of two critically endangered mammalian herbivores. Commun Biol 2024; 7:333. [PMID: 38491117 PMCID: PMC10943211 DOI: 10.1038/s42003-024-05983-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 02/27/2024] [Indexed: 03/18/2024] Open
Abstract
Optimal foraging theory predicts that animals maximise energy intake by consuming the most valuable foods available. When resources are limited, they may include lower-quality fallback foods in their diets. As seasonal herbivore diet switching is understudied, we evaluate its extent and effects across three Kenyan reserves each for Critically Endangered eastern black rhino (Diceros bicornis michaeli) and Grevy's zebra (Equus grevyi), and its associations with habitat quality, microbiome variation, and reproductive performance. Black rhino diet breadth increases with vegetation productivity (NDVI), whereas zebra diet breadth peaks at intermediate NDVI. Black rhino diets associated with higher vegetation productivity have less acacia (Fabaceae: Vachellia and Senegalia spp.) and more grass suggesting that acacia are fallback foods, upending conventional assumptions. Larger dietary shifts are associated with longer calving intervals. Grevy's zebra diets in high rainfall areas are consistently grass-dominated, whereas in arid areas they primarily consume legumes during low vegetation productivity periods. Whilst microbiome composition between individuals is affected by the environment, and diet composition in black rhino, seasonal dietary shifts do not drive commensurate microbiome shifts. Documenting diet shifts across ecological gradients can increase the effectiveness of conservation by informing habitat suitability models and improving understanding of responses to resource limitation.
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Affiliation(s)
- Nick Harvey Sky
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK.
- North of England Zoological Society, Chester Zoo, Upton-by-Chester, CH2 1LH, UK.
| | - Jake Britnell
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK
- North of England Zoological Society, Chester Zoo, Upton-by-Chester, CH2 1LH, UK
| | - Rachael Antwis
- School of Environment and Life Sciences, University of Salford, Salford, M5 4WX, UK
| | - Tyler Kartzinel
- Department of Ecology, Evolution, and Organismal Biology, Brown University, 85 Waterman Street, Providence, RI, 02912, USA
- Institute at Brown for Environment and Society, Brown University, 85 Waterman Street, Providence, RI, 02912, USA
| | - Daniel Rubenstein
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, 08544-2016, USA
| | - Phil Toye
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Benedict Karani
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Regina Njeru
- International Livestock Research Institute and Centre for Tropical Livestock Genetics and Health, Nairobi, P.O. Box 30709-00100, Kenya
| | - Danielle Hinchcliffe
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, L3 3AF, UK
| | | | | | - Susanne Shultz
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9NT, UK
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2
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Scott SE, Cain B, de Kort SR, Johnson B, Khayale C, Versteege L, Bettridge CM. Group composition impacts reproductive output and population viability in captive white rhinoceros. Anim Conserv 2022. [DOI: 10.1111/acv.12833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- S. E. Scott
- Department of Natural Sciences, Ecology and Environment Research Centre Manchester Metropolitan University Manchester UK
- Joint Nature Conservation Committee Aberdeen UK
| | - B. Cain
- Department of Natural Sciences, Ecology and Environment Research Centre Manchester Metropolitan University Manchester UK
| | - S. R. de Kort
- Department of Natural Sciences, Ecology and Environment Research Centre Manchester Metropolitan University Manchester UK
| | | | | | - L. Versteege
- Safaripark Beekse Bergen Hilvarenbeek The Netherlands
| | - C. M. Bettridge
- Department of Natural Sciences, Ecology and Environment Research Centre Manchester Metropolitan University Manchester UK
- School of Natural Sciences Bangor University Bangor UK
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3
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Chimes LC, Beytell P, Muntifering JR, Kötting B, Neville V. Effects of dehorning on population productivity in four Namibia sub-populations of black rhinoceros (Diceros bicornis bicornis). EUR J WILDLIFE RES 2022; 68:58. [PMID: 35992995 PMCID: PMC9378341 DOI: 10.1007/s10344-022-01607-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 08/01/2022] [Accepted: 08/06/2022] [Indexed: 12/02/2022]
Abstract
The black rhinoceros (rhino) (Diceros bicornis) is critically endangered, with poaching being one of several threats to the species’ survival. Many reserves across several countries, including Namibia, South Africa, and Zimbabwe, now dehorn their rhinos in an attempt to reduce poaching. Historical data collected by the Namibian Ministry of Environment, Forestry, and Tourism and Save the Rhino Trust were used to investigate whether dehorning has an effect on age at first reproduction (AFR), inter-calving interval (ICI), birth sex ratios, calf survival, cause of death, and lifespan. These were assessed in four Namibian sub-populations (hereafter referred to as ‘populations’) of black rhino (denoted A, B, C, and D) which have undergone varying levels of dehorning. No significant difference was found in any of the variables between dehorned and horned individuals. Population was a significant predictor of AFR (LRT = 7.433, p = 0.024) and ICI (LRT = 13.281, p = 0.004), although pairwise comparisons only found populations A and B to be significantly different (AFR: z = −2.736, p = 0.017, ICI: z = −3.705, p = 0.001). Additionally, a significantly higher number of males than females were born in population D (p = 0.021, CI = 0.544, 0.960). The main cause of death across all individuals was poaching, although there was no significant difference in the proportion of rhinos poached between dehorned and horned individuals (X2 = 0.638, p = 0.424, n = 265). No evidence was found to suggest that dehorning has any effect on AFR, ICI, birth sex ratios, calf survival, or lifespan in the black rhino, which is reassuring in the continued use of dehorning as an anti-poaching technique in this species.
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Affiliation(s)
- Lucy C. Chimes
- Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU UK
| | - Piet Beytell
- Ministry of Environment, Forestry and Tourism, P/Bag 13306, Windhoek, Namibia
| | - Jeff R. Muntifering
- Save the Rhino Trust, PO Box 2159, Swakopmund, Namibia
- Great Plains Zoo, 805 S. Kiwanis Avenue, Sioux Falls, SD USA
- Namibia University of Science and Technology, Private Bag 13388, Windhoek, Namibia
| | - Birgit Kötting
- Ministry of Environment, Forestry and Tourism, P/Bag 13306, Windhoek, Namibia
| | - Vikki Neville
- Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU UK
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4
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Pfannerstill V, Signer J, Fitt M, Burger K, Balkenhol N, Bennitt E. Effects of age and sex on site fidelity, movement ranges and home ranges of white and black rhinoceros translocated to the Okavango Delta, Botswana. Afr J Ecol 2022. [DOI: 10.1111/aje.13011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Johannes Signer
- Wildlife Sciences University of Goettingen Göttingen Germany
| | | | | | - Niko Balkenhol
- Wildlife Sciences University of Goettingen Göttingen Germany
| | - Emily Bennitt
- Okavango Research Institute University of Botswana Maun Botswana
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5
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Harvey Sky N, Jackson J, Chege G, Gaymer J, Kimiti D, Mutisya S, Nakito S, Shultz S. Female reproductive skew exacerbates the extinction risk from poaching in the eastern black rhino. Proc Biol Sci 2022; 289:20220075. [PMID: 35414243 PMCID: PMC9006021 DOI: 10.1098/rspb.2022.0075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Variation in individual demographic rates can have large consequences for populations. Female reproductive skew is an example of structured demographic heterogeneity where females have intrinsic qualities that make them more or less likely to breed. The consequences of reproductive skew for population dynamics are poorly understood in non-cooperatively breeding mammals, especially when coupled with other drivers such as poaching. We address this knowledge gap with population viability analyses using an age-specific, female-only, individual-based, stochastic population model built with long-term data for three Kenyan populations of the Critically Endangered eastern black rhino (Diceros bicornis michaeli). There was substantial reproductive skew, with a high proportion of females not breeding or doing so at very low rates. This had a large impact on the projected population growth rate for the smaller population on Ol Jogi. Moreover, including female reproductive skew exacerbates the effects of poaching, increasing the probability of extinction by approximately 70% under a simulated poaching pressure of 5% offtake per year. Tackling the effects of reproductive skew depends on whether it is mediated by habitat or social factors, with potential strategies including habitat and biological management respectively. Investigating and tackling reproductive skew in other species requires long-term, individual-level data collection.
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Affiliation(s)
- Nick Harvey Sky
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PL, UK.,North of England Zoological Society, Chester Zoo, Caughall Road, Chester CH2 1LH, UK
| | - John Jackson
- Department of Zoology, University of Oxford, Oxford OX1 3SZ, UK
| | - Geoffrey Chege
- Lewa Wildlife Conservancy, PO Box, Private Bag, Isiolo 60300, Kenya
| | | | - David Kimiti
- Grevy's Zebra Trust, PO Box 15351-00509, Nairobi, Kenya
| | | | - Simon Nakito
- Ol Pejeta Conservancy, PO Box 167, Nanyuki, Kenya
| | - Susanne Shultz
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PL, UK
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6
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Stratford KJ, Guerier AS, Crawford SJ, Stratford SMC, Schmidt-Küntzel A, Bishop JM. Female Southern White Rhinoceros Can Select Mates to Avoid Inbreeding. J Hered 2021; 112:385-390. [PMID: 33950221 DOI: 10.1093/jhered/esab028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/30/2021] [Indexed: 01/02/2023] Open
Abstract
Current management models for many endangered species focus primarily on demographic recovery, often ignoring their intrinsic ecological requirements. Across the protected area network of southern Africa, most southern white rhinoceros are managed in populations of less than 50 individuals, experiencing restricted dispersal opportunities, and limited breeding male numbers due to their exclusive home range requirements. In the absence of information on the breeding structure of these populations, poor management decisions may require females to either forego a breeding opportunity or select to inbreed with close relatives. Here, we use a combination of social pedigree data together with genetic analyses to reconstruct the parentage of all 28 offspring produced in a 5-year period in a managed free-ranging southern white rhinoceros population. During this period, all breeding females (founders and first-generation daughters) had access to both a founder male (father to most of the daughters) and two recently introduced inexperienced males. We report that while founder females were more likely to breed with the founder male, their daughters, in contrast, were more likely to breed with the introduced males, thus avoiding inbreeding. However, we also found evidence of father-daughter inbreeding in this population, and contend that in the absence of choice, rather than forego a breeding opportunity, female white rhinoceros will inbreed with their fathers. We argue that to effectively conserve the southern white rhinoceros, managers need to understand the breeding structure of these small populations, particularly in terms of parentage and kinship.
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Affiliation(s)
| | | | | | | | - Anne Schmidt-Küntzel
- Life Technologies Conservation Genetics Laboratory, Cheetah Conservation Fund, Otjiwarongo, Namibia
| | - Jacqueline M Bishop
- Institute for Communities and Wildlife in Africa, Department of Biological Sciences, University of Cape Town, Rondebosch, Cape Town, South Africa
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7
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Labonne J, Manicki A, Chevalier L, Tétillon M, Guéraud F, Hendry AP. Using Reciprocal Transplants to Assess Local Adaptation, Genetic Rescue, and Sexual Selection in Newly Established Populations. Genes (Basel) 2020; 12:genes12010005. [PMID: 33374534 PMCID: PMC7822186 DOI: 10.3390/genes12010005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/14/2020] [Accepted: 12/18/2020] [Indexed: 12/11/2022] Open
Abstract
Small populations establishing on colonization fronts have to adapt to novel environments with limited genetic variation. The pace at which they can adapt, and the influence of genetic variation on their success, are key questions for understanding intraspecific diversity. To investigate these topics, we performed a reciprocal transplant experiment between two recently founded populations of brown trout in the sub-Antarctic Kerguelen Islands. Using individual tagging and genetic assignment methods, we tracked the fitness of local and foreign individuals, as well as the fitness of their offspring over two generations. In both populations, although not to the same extent, gene flow occurred between local and foreign gene pools. In both cases, however, we failed to detect obvious footprints of local adaptation (which should limit gene flow) and only weak support for genetic rescue (which should enhance gene flow). In the population where gene flow from foreign individuals was low, no clear differences were observed between the fitness of local, foreign, and F1 hybrid individuals. In the population where gene flow was high, foreign individuals were successful due to high mating success rather than high survival, and F1 hybrids had the same fitness as pure local offspring. These results suggest the importance of considering sexual selection, rather than just local adaptation and genetic rescue, when evaluating the determinants of success in small and recently founded populations.
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Affiliation(s)
- Jacques Labonne
- Université de Pau et des Pays de l’Adour, UMR INRAE-UPPA, Ecobiop, FR-64310 Saint-Pée sur Nivelle, France; (A.M.); (L.C.); (M.T.); (F.G.)
- Correspondence: (J.L.); (A.P.H.)
| | - Aurélie Manicki
- Université de Pau et des Pays de l’Adour, UMR INRAE-UPPA, Ecobiop, FR-64310 Saint-Pée sur Nivelle, France; (A.M.); (L.C.); (M.T.); (F.G.)
| | - Louise Chevalier
- Université de Pau et des Pays de l’Adour, UMR INRAE-UPPA, Ecobiop, FR-64310 Saint-Pée sur Nivelle, France; (A.M.); (L.C.); (M.T.); (F.G.)
| | - Marin Tétillon
- Université de Pau et des Pays de l’Adour, UMR INRAE-UPPA, Ecobiop, FR-64310 Saint-Pée sur Nivelle, France; (A.M.); (L.C.); (M.T.); (F.G.)
| | - François Guéraud
- Université de Pau et des Pays de l’Adour, UMR INRAE-UPPA, Ecobiop, FR-64310 Saint-Pée sur Nivelle, France; (A.M.); (L.C.); (M.T.); (F.G.)
| | - Andrew P. Hendry
- Redpath Museum and Department of Biology, McGill University, Montreal, QC H3A 0C4, Canada
- Correspondence: (J.L.); (A.P.H.)
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8
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le Roex N, Paxton M, Adendorff J, Ferreira S, O'Riain MJ. Starting small: long‐term consequences in a managed large‐mammal population. J Zool (1987) 2018. [DOI: 10.1111/jzo.12572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- N. le Roex
- Institute for Communities and Wildlife in Africa (iCWild) Department of Biological Sciences University of Cape Town Cape Town South Africa
- School of Biology and Environmental Sciences University of Mpumalanga Mbombela South Africa
| | - M. Paxton
- Conservation Management South African National Parks Addo Elephant National Park Port Elizabeth South Africa
| | - J. Adendorff
- Conservation Management South African National Parks Addo Elephant National Park Port Elizabeth South Africa
| | - S. Ferreira
- Scientific Services South African National Parks Skukuza South Africa
| | - M. J. O'Riain
- Institute for Communities and Wildlife in Africa (iCWild) Department of Biological Sciences University of Cape Town Cape Town South Africa
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9
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Heterozygosity–behavior and heterozygosity–fitness correlations in a salamander with limited dispersal. POPUL ECOL 2018. [DOI: 10.1007/s10144-017-0604-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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10
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Head ML, Kahn AT, Henshaw JM, Keogh JS, Jennions MD. Sexual selection on male body size, genital length and heterozygosity: Consistency across habitats and social settings. J Anim Ecol 2017; 86:1458-1468. [PMID: 28815592 DOI: 10.1111/1365-2656.12742] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 07/30/2017] [Indexed: 12/22/2022]
Abstract
Spatial and temporal variation in environmental factors and the social setting can help to maintain genetic variation in sexually selected traits if it affects the strength of directional selection. A key social parameter which affects the intensity of, and sometimes predicts the response to, mating competition is the operational sex ratio (OSR; ratio of receptive males to females). How the OSR affects selection for specific male traits is poorly understood. It is also unclear how sexual selection is affected by interactions between the OSR and environmental factors, such as habitat complexity, that alter key male-female interactions such as mate encounter rates. Here, we experimentally manipulated the OSR and habitat complexity and quantified sexual selection on male mosquitofish (Gambusia holbrooki) by directly measuring male reproductive success (i.e. paternity). We show that despite a more equitable sharing of paternity (i.e. higher levels of multiple paternity) under a male-biased OSR, selection on focal male traits was unaffected by the OSR or habitat complexity. Instead, sexual selection consistently, and significantly, favoured smaller bodied males, males with higher genome wide heterozygosity (based on >3,000 SNP markers) and males with a relatively long gonopodium (intromittent organ). Our results show that sexual selection on male body size, relative genital size and heterozygosity in this system is consistent across environments that vary in ecological parameters that are expected to influence mate encounter rates.
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Affiliation(s)
- Megan L Head
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - Andrew T Kahn
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - Jonathan M Henshaw
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - J Scott Keogh
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
| | - Michael D Jennions
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australia
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11
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Grueber CE, Fitzpatrick JL, Devigili A, Gasparini C, Ramnarine IW, Evans JP. Population demography and heterozygosity-fitness correlations in natural guppy populations: An examination using sexually selected fitness traits. Mol Ecol 2017; 26:4631-4643. [PMID: 28734054 DOI: 10.1111/mec.14243] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 06/12/2017] [Indexed: 11/30/2022]
Abstract
Heterozygosity-fitness correlations (HFCs) have been examined in a wide diversity of contexts, and the results are often used to infer the role of inbreeding in natural populations. Although population demography, reflected in population-level genetic parameters such as allelic diversity or identity disequilibrium, is expected to play a role in the emergence and detectability of HFCs, direct comparisons of variation in HFCs across many populations of the same species, with different genetic histories, are rare. Here, we examined the relationship between individual microsatellite heterozygosity and a range of sexually selected traits in 660 male guppies from 22 natural populations in Trinidad. Similar to previous studies, observed HFCs were weak overall. However, variation in HFCs among populations was high for some traits (although these variances were not statistically different from zero). Population-level genetic parameters, specifically genetic diversity levels (number of alleles, observed/expected heterozygosity) and measures of identity disequilibrium (g2 and heterozygosity-heterozygosity correlations), were not associated with variation in population-level HFCs. This latter result indicates that these metrics do not necessarily provide a reliable predictor of HFC effect sizes across populations. Importantly, diversity and identity disequilibrium statistics were not correlated, providing empirical evidence that these metrics capture different essential characteristics of populations. A complex genetic architecture likely underpins multiple fitness traits, including those associated with male fitness, which may have reduced our ability to detect HFCs in guppy populations. Further advances in this field would benefit from additional research to determine the demographic contexts in which HFCs are most likely to occur.
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Affiliation(s)
- Catherine E Grueber
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia.,San Diego Zoo Global, San Diego, CA, USA.,Department of Zoology, University of Otago, Dunedin, New Zealand
| | - John L Fitzpatrick
- Department of Zoology, Stockholm University, Stockholm, Sweden.,Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, WA, Australia
| | - Alessandro Devigili
- Department of Zoology, Stockholm University, Stockholm, Sweden.,Department of Biology, University of Padova, Padua, Italy
| | - Clelia Gasparini
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, WA, Australia
| | - Indar W Ramnarine
- Department of Life Sciences, University of the West Indies, St Augustine, Trinidad and Tobago
| | - Jonathan P Evans
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, WA, Australia
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12
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Lemaître JF, Gaillard JM. Reproductive senescence: new perspectives in the wild. Biol Rev Camb Philos Soc 2017; 92:2182-2199. [PMID: 28374548 DOI: 10.1111/brv.12328] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 02/23/2017] [Accepted: 03/03/2017] [Indexed: 11/26/2022]
Abstract
According to recent empirical studies, reproductive senescence, the decline in reproductive success with increasing age, seems to be nearly ubiquitous in the wild. However, a clear understanding of the evolutionary causes and consequences of reproductive senescence is still lacking and requires new and integrative approaches. After identifying the sequential and complex nature of female reproductive senescence, we show that the relative contributions of physiological decline and alterations in the efficiency of parental care to reproductive senescence remain unknown and need to be assessed in the light of current evolutionary theories of ageing. We demonstrate that, although reproductive senescence is generally studied only from the female viewpoint, age-specific female reproductive success strongly depends on male-female interactions. Thus, a reduction in male fertilization efficiency with increasing age has detrimental consequences for female fitness. Lastly, we call for investigations of the role of environmental conditions on reproductive senescence, which could provide salient insights into the underlying sex-specific mechanisms of reproductive success. We suggest that embracing such directions should allow building new bridges between reproductive senescence and the study of sperm competition, parental care, mate choice and environmental conditions.
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Affiliation(s)
- Jean-François Lemaître
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR5558, F-69622, Villeurbanne, France
| | - Jean-Michel Gaillard
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR5558, F-69622, Villeurbanne, France
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13
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Vega‐Trejo R, Head ML, Keogh JS, Jennions MD. Experimental evidence for sexual selection against inbred males. J Anim Ecol 2017; 86:394-404. [DOI: 10.1111/1365-2656.12615] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 11/24/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Regina Vega‐Trejo
- Division of Ecology and Evolution, Research School of Biology The Australian National University, Acton Canberra ACT 2601 Australia
| | - Megan L. Head
- Division of Ecology and Evolution, Research School of Biology The Australian National University, Acton Canberra ACT 2601 Australia
| | - J. Scott Keogh
- Division of Ecology and Evolution, Research School of Biology The Australian National University, Acton Canberra ACT 2601 Australia
| | - Michael D. Jennions
- Division of Ecology and Evolution, Research School of Biology The Australian National University, Acton Canberra ACT 2601 Australia
- Wissenschaftskolleg zu Berlin Wallotstraße 19 14193 Berlin Germany
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14
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Cézilly F, Quinard A, Motreuil S, Pradel R. Adult survival selection in relation to multilocus heterozygosity and body size in a tropical bird species, the Zenaida dove, Zenaida aurita. Oecologia 2015; 180:127-36. [PMID: 26433960 DOI: 10.1007/s00442-015-3466-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 09/23/2015] [Indexed: 01/10/2023]
Abstract
Both phenotypic and genetic quality can influence the survival of individuals through time, although their relative influences are rarely addressed simultaneously. Here we used capture-mark-recapture modelling to assess the influence of both multilocus heterozygosity (MLH) and body size on apparent adult survival in a tropical bird species, the Zenaida dove, Zenaida aurita, using a sample of 391 individuals genotyped at 11 microsatellites, while controlling for the effects of sex. No effect of body size on either adult survival or capture rate was found. In the best model, survival was a logit linear function of MLH, whereas detection probability was a sex-dependent logit linear function of the logarithm of field effort, increasing with time and affected by a random individual effect. Using a Bayesian approach, we found that MLH explained 1.14% of the total deviance, as expected from theory and previous studies of heterozygosity-fitness correlations, with no evidence for local effects. However, results from capture-mark-recapture modelling indicated that expected longevity varied from 4.8 years in the least heterozygous individuals (MLH = 0.37) to 10.6 years in the most heterozygous ones (MLH = 1), thus suggesting that MLH had potentially a substantial effect on survival. We discuss our results in relation to current hypotheses about the origin of heterozygosity-fitness correlations.
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Affiliation(s)
- Frank Cézilly
- Université de Bourgogne, UMR CNRS 6282 Biogéosciences, 6 boulevard Gabriel, 21000, Dijon, France.
| | - Aurélie Quinard
- Université de Bourgogne, UMR CNRS 6282 Biogéosciences, 6 boulevard Gabriel, 21000, Dijon, France
| | - Sébastien Motreuil
- Université de Bourgogne, UMR CNRS 6282 Biogéosciences, 6 boulevard Gabriel, 21000, Dijon, France
| | - Roger Pradel
- CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, Montpellier, France
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15
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Edwards KL, Shultz S, Pilgrim M, Walker SL. Male reproductive success is correlated with testosterone in the eastern black rhinoceros (Diceros bicornis michaeli). Gen Comp Endocrinol 2015; 213:40-9. [PMID: 25562628 DOI: 10.1016/j.ygcen.2014.12.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 12/15/2014] [Accepted: 12/26/2014] [Indexed: 10/24/2022]
Abstract
Among natural populations of polygynous species, males often vary in their lifetime reproductive success. However, in managed populations of endangered species, either in situ or as part of captive breeding programmes, it is important to understand why differences in reproductive success occur. The European captive population of the critically endangered eastern black rhinoceros is currently under-performing relative to their wild counterparts, with low reproductive output and high reproductive skew limiting growth and genetic diversity. To investigate why over 40% of captive males fail to breed, faecal samples were collected weekly from 23 males at 12 institutions across Europe for 4-32 months. Testosterone metabolite concentration was compared between proven and non-proven males and a number of intrinsic and extrinsic factors that could influence reproductive success were also investigated. Males that sired within the last 3½ years had significantly higher androgen concentrations than non-proven males, and average testosterone was positively correlated with the number of offspring sired per year spent in the reproductive age class. Proven and non-proven males did not differ in their body condition, or in average faecal glucocorticoid concentration. Differences in individual temperament were associated with adrenal activity, but did not correlate with reproductive category. Highest testosterone concentrations were observed in proven males that were housed with females during oestrus, and lowest concentrations in non-proven females not housed with females at all during the study period. Further work is necessary to determine whether proven males had higher testosterone due to underlying differences associated with quality, or whether external stimuli such as access to females could influence testosterone concentration and increase a male's chances of becoming a successful breeder.
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Affiliation(s)
- Katie L Edwards
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK; North of England Zoological Society, Chester Zoo, Chester CH2 1LH, UK.
| | - Susanne Shultz
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Mark Pilgrim
- North of England Zoological Society, Chester Zoo, Chester CH2 1LH, UK
| | - Susan L Walker
- North of England Zoological Society, Chester Zoo, Chester CH2 1LH, UK
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