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Plaisir CA, King WJ, Forsyth DM, Festa-Bianchet M. Effects of rainfall, forage biomass, and population density, on survival and growth of juvenile kangaroos. J Mammal 2022. [DOI: 10.1093/jmammal/gyab132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
A central goal of ecology is to understand how environmental variation affects populations. Long-term studies of marked individuals can quantify the effects of environmental variation on key life-history traits. We monitored the survival and growth of 336 individually marked juvenile eastern grey kangaroos (Macropus giganteus), a large herbivore living in a seasonal but unpredictable environment. During our 12-year study, the population experienced substantial variation in rainfall, forage biomass, and density. We used structural equation modeling to determine how variation in temperature and rainfall affected juvenile survival and growth through its effect on forage biomass and population density. Independently of population density, forage biomass had strong positive effects on survival from 10 to 21 months. At low population density, forage biomass also had a positive effect on skeletal growth to 26 months. Increasing maternal body condition improved rearing success for daughters but not for sons. High population density reduced skeletal growth to 26 months for both sexes. Rainfall had an increasingly positive effect on forage biomass at high temperatures, indicating a seasonal effect on food availability. Our study reveals interacting effects of environmental variation on juvenile survival and growth for a large mammal with a conservative reproductive strategy that experiences substantial stochasticity in food availability.
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Affiliation(s)
- Charles-Alexandre Plaisir
- Département de Biologie, Université de Sherbrooke, 2500, Boulevard de l’Université, Sherbrooke, QC J1K 2R1, Canada
| | - Wendy J King
- Département de Biologie, Université de Sherbrooke, 2500, Boulevard de l’Université, Sherbrooke, QC J1K 2R1, Canada
- Research School of Biology, Australian National University, 134, Linnaeus Way, Acton, ACT 2601, Australia
| | - David M Forsyth
- Vertebrate Pest Research Unit, NSW Department of Primary Industries, 1447 Forest Road, Orange, NSW 2800, Australia
- School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Marco Festa-Bianchet
- Département de Biologie, Université de Sherbrooke, 2500, Boulevard de l’Université, Sherbrooke, QC J1K 2R1, Canada
- Research School of Biology, Australian National University, 134, Linnaeus Way, Acton, ACT 2601, Australia
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2
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Albanese MS, Ojeda RA, Astié AA. Delayed mortality of males in Thylamys bruchi, a semelparous marsupial from the Monte Desert, Argentina. J Mammal 2020. [DOI: 10.1093/jmammal/gyaa139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Male-only obligate semelparity is a well-studied reproductive strategy in some Australian marsupials. This strategy has not been documented in South American species, although semelparity in both sexes occurs in some Neotropical didelphids. The fat-tailed mouse opossum, Thylamys bruchi, is an endemic species of the temperate Monte Desert, in Argentina. Seasonality and predictability of resources are two of the attributes associated with habitats where marsupial semelparity has evolved, and both are characteristic of the Monte Desert. We aimed to characterize the life-history strategy of T. bruchi to explore if it can be considered a semelparous species. We studied a fat-tailed mouse opossum population for 7 years with two different capture techniques (Sherman traps and nest boxes). Thylamys bruchi showed strong seasonality in abundance, with the highest captures during summer and autumn. Reproduction and weaning coincided with the most favorable period of the year with respect to climate and resource availability. Every year we observed a single cohort with little overlap until weaning of young. After breeding, all adults disappeared from the population; however, unlike any other didelphids, males showed delayed mortality and died, along with females, after weaning. We found no evidence of survival to a second breeding season for either sex. We therefore propose T. bruchi as a desert-dwelling marsupial with a semelparous reproductive strategy. Because the severity of winters may be acting as an important constraint on the energetic balance of adults in this population, we propose that challenging climatic conditions, coupled with the seasonality and high predictability of food resources, may have contributed to the evolution of the extreme reproductive strategy in this didelphid marsupial.
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Affiliation(s)
- M Soledad Albanese
- Instituto Argentino de Investigaciones de las Zonas Áridas (IADIZA-CONICET), Av. Ruiz Leal s/n, Parque Gral. San Martín, Mendoza, Argentina
- Grupo de Investigaciones de la Biodiversidad (GiB), IADIZA, CCT Mendoza-CONICET, Av. Ruiz Leal s/n, Parque Gral. San Martín, Mendoza, Argentina
| | - Ricardo A Ojeda
- Instituto Argentino de Investigaciones de las Zonas Áridas (IADIZA-CONICET), Av. Ruiz Leal s/n, Parque Gral. San Martín, Mendoza, Argentina
- Grupo de Investigaciones de la Biodiversidad (GiB), IADIZA, CCT Mendoza-CONICET, Av. Ruiz Leal s/n, Parque Gral. San Martín, Mendoza, Argentina
| | - Andrea A Astié
- Instituto Argentino de Investigaciones de las Zonas Áridas (IADIZA-CONICET), Av. Ruiz Leal s/n, Parque Gral. San Martín, Mendoza, Argentina
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3
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Jehan C, Sabarly C, Rigaud T, Moret Y. Late-life reproduction in an insect: Terminal investment, reproductive restraint or senescence. J Anim Ecol 2020; 90:282-297. [PMID: 33051872 DOI: 10.1111/1365-2656.13367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 09/09/2020] [Indexed: 01/28/2023]
Abstract
The terminal investment, reproductive restraint or senescence theories may explain individual late-life patterns of reproduction. The terminal investment hypothesis predicts that individuals increase reproductive allocation late in life as prospects for future survival decrease. The other two hypotheses predict reduced reproduction late in life, but for different reasons. Under the Reproductive Restraint hypothesis, individuals restrain their reproductive effort to sustain future survival and gain more time for reproducing, whereas under the Senescence process, reproduction is constrained because of somatic deterioration. While these hypotheses imply that reproduction is costly, they should have contrasted implications in terms of survival after late reproduction and somatic maintenance. Testing these hypotheses requires proper consideration of the effects of age-dependent reproductive effort on post-reproduction survival and age-related somatic functions. We experimentally tested these three hypotheses in females of the mealworm beetle, Tenebrio molitor, an iteroparous and income breeder insect. We manipulated their age-specific allocation into reproduction and observed the effects of this manipulation on their late-life fecundity, post-reproduction survival and immunocompetence as a measurement of somatic protection. We found that females exhibit age-related decline in fecundity and that this reproductive senescence is accelerated by a cost of early reproduction. The cost of reproduction had no significant effect on female longevity and their ability to survive a bacterial infection, despite that some immune cells were depleted by reproduction. We found that female post-infection survival deteriorated with age, which could be partly explained by a decline in some immune parameters. Importantly, females did not increase their reproductive effort late in life at the expense of their late-life post-reproduction survival. Late-life reproduction in T. molitor females is senescing and not consistent with a terminal investment strategy. Rather, our results suggest that females allocate resources according to a priority scheme favouring longevity at the expense of reproduction, which is in line with the reproductive restraint hypothesis. Such a priority scheme also shows that a relatively short-lived insect can evolve life-history strategies hitherto known only in long-lived animals. This puts in perspective the role of longevity in the evolution of life-history strategies.
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Affiliation(s)
- Charly Jehan
- UMR CNRS 6282 BioGéoSciences, Équipe Écologie Évolutive, Université Bourgogne-Franche Comté, Dijon, France
| | - Camille Sabarly
- UMR CNRS 6282 BioGéoSciences, Équipe Écologie Évolutive, Université Bourgogne-Franche Comté, Dijon, France
| | - Thierry Rigaud
- UMR CNRS 6282 BioGéoSciences, Équipe Écologie Évolutive, Université Bourgogne-Franche Comté, Dijon, France
| | - Yannick Moret
- UMR CNRS 6282 BioGéoSciences, Équipe Écologie Évolutive, Université Bourgogne-Franche Comté, Dijon, France
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4
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Kroeger SB, Blumstein DT, Armitage KB, Reid JM, Martin JGA. Older mothers produce more successful daughters. Proc Natl Acad Sci U S A 2020; 117:4809-4814. [PMID: 32071200 PMCID: PMC7060700 DOI: 10.1073/pnas.1908551117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Annual reproductive success and senescence patterns vary substantially among individuals in the wild. However, it is still seldom considered that senescence may not only affect an individual but also affect age-specific reproductive success in its offspring, generating transgenerational reproductive senescence. We used long-term data from wild yellow-bellied marmots (Marmota flaviventer) living in two different elevational environments to quantify age-specific reproductive success of daughters born to mothers differing in age. Contrary to prediction, daughters born to older mothers had greater annual reproductive success on average than daughters born to younger mothers, and this translated into greater lifetime reproductive success. However, in the favorable lower elevation environment, daughters born to older mothers also had greater age-specific decreases in annual reproductive success. In the harsher higher elevation environment on the other hand, daughters born to older mothers tended to die before reaching ages at which such senescent decreases could be observed. Our study highlights the importance of incorporating environment-specific transgenerational parent age effects on adult offspring age-specific life-history traits to fully understand the substantial variation observed in senescence patterns in wild populations.
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Affiliation(s)
- Svenja B Kroeger
- School of Biological Sciences, Zoology Building, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom;
- Department of Landscape and Biodiversity, The Norwegian Institute of Bioeconomy Research, 7031 Trondheim, Norway
| | - Daniel T Blumstein
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095-1606
- The Rocky Mountain Biological Laboratory, Crested Butte, CO 81224
| | - Kenneth B Armitage
- The Rocky Mountain Biological Laboratory, Crested Butte, CO 81224
- Department of Ecology & Evolutionary Biology, The University of Kansas, Lawrence, KS 66045-7534
| | - Jane M Reid
- School of Biological Sciences, Zoology Building, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, Realfagbygget, Gløshaugen, N-7491 Trondheim, Norway
| | - Julien G A Martin
- School of Biological Sciences, Zoology Building, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
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5
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Michel ES, Demarais S, Strickland BK, Belant JL, Castle LE. Body mass influences maternal allocation more than parity status for a long-lived cervid mother. J Mammal 2019. [DOI: 10.1093/jmammal/gyz107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Abstract
Mothers should balance the risk and reward of allocating resources to offspring to optimize the reproductive value of both offspring and mother while maximizing lifetime reproductive success by producing high-quality litters. The reproductive restraint hypothesis suggests maternal allocation should peak for prime-aged mothers and be less for younger mothers such that body condition is not diminished to a level that would jeopardize their survival or future reproductive events. We assessed if reproductive tactics varied by maternal body mass and parity status in captive female white-tailed deer (Odocoileus virginianus) to determine if prime-aged mothers allocate relatively more resources to reproduction than primiparous mothers. Maternal body mass, not parity status, positively affected maternal allocation, with heavier mothers producing both heavy litters and heavy individual offspring. Conversely, maternal body mass alone did not affect litter size, rather the interaction between maternal body mass and parity status positively affected litter size such that maternal body mass displayed a greater effect on litter size for primiparous than multiparous mothers. Our results suggest that heavy white-tailed deer mothers allocate additional resources to current year reproduction, which may be an adaptation allowing mothers to produce high-quality litters and increase their annual reproductive success because survival to the next reproductive attempt is not certain.
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Affiliation(s)
- Eric S Michel
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, USA
| | - Stephen Demarais
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, USA
| | - Bronson K Strickland
- Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, Mississippi State, MS, USA
| | - Jerrold L Belant
- Camp Fire Program in Wildlife Conservation, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Larry E Castle
- Mississippi Department of Wildlife, Fisheries and Parks, Jackson, MS, USA
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6
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Campbell RD, Rosell F, Newman C, Macdonald DW. Age-related changes in somatic condition and reproduction in the Eurasian beaver: Resource history influences onset of reproductive senescence. PLoS One 2017; 12:e0187484. [PMID: 29206840 PMCID: PMC5716577 DOI: 10.1371/journal.pone.0187484] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 10/20/2017] [Indexed: 11/18/2022] Open
Abstract
Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber), we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5-6. Rainfall, an established negative proxy of annual resource availability for beavers, was consistently associated with lower reproductive output for females of all ages. In contrast, breeding territory quality, as a measure of local resource history over reproductive lifetimes, caused differences in individual patterns of reproductive senescence; animals from lower quality territories senesced when younger. Litter size was unrelated to maternal age, although adult body weight increased with age. In terms of resource effects, in poorer years but not in better years, older mothers produced larger offspring than did younger mothers, giving support to the constraint theory. Overall, our findings exemplify state-dependent life-history strategies, supporting an effect of resources on reproductive senescence, where cumulative differences in resource access, and not just reproductive strategy, mediate long-term reproductive trade-offs, consistent with the disposable soma and reproductive restraint theories. We propose that flexible life-history schedules could play a role in the dynamics of populations exhibiting reproductive skew, with earlier breeding opportunities leading to an earlier senescence schedule through resource dependent mechanisms.
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Affiliation(s)
- Ruairidh D. Campbell
- University College of Southeast Norway, Department of Natural Sciences and Environmental Health, Bø i Telemark, Norway
- Wildlife Conservation Research Unit, The Recanati-Kaplan Centre, Zoology Department, University of Oxford, Tubney, United Kingdom
| | - Frank Rosell
- University College of Southeast Norway, Department of Natural Sciences and Environmental Health, Bø i Telemark, Norway
- * E-mail:
| | - Chris Newman
- Wildlife Conservation Research Unit, The Recanati-Kaplan Centre, Zoology Department, University of Oxford, Tubney, United Kingdom
| | - David W. Macdonald
- Wildlife Conservation Research Unit, The Recanati-Kaplan Centre, Zoology Department, University of Oxford, Tubney, United Kingdom
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7
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Zhang Y, Hood WR. Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms. ACTA ACUST UNITED AC 2017; 219:3177-3189. [PMID: 27802148 DOI: 10.1242/jeb.132183] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Oxidative damage is predicted to be a mediator of trade-offs between current reproduction and future reproduction or survival, but most studies fail to support such predictions. We suggest that two factors underlie the equivocal nature of these findings: (1) investigators typically assume a negative linear relationship between current reproduction and future reproduction or survival, even though this is not consistently shown by empirical studies; and (2) studies often fail to target mechanisms that could link interactions between sequential life-history events. Here, we review common patterns of reproduction, focusing on the relationships between reproductive performance, survival and parity in females. Observations in a range of species show that performance between sequential reproductive events can decline, remain consistent or increase. We describe likely bioenergetic consequences of reproduction that could underlie these changes in fitness, including mechanisms that could be responsible for negative effects being ephemeral, persistent or delayed. Finally, we make recommendations for designing future studies. We encourage investigators to carefully consider additional or alternative measures of bioenergetic function in studies of life-history trade-offs. Such measures include reactive oxygen species production, oxidative repair, mitochondrial biogenesis, cell proliferation, mitochondrial DNA mutation and replication error and, importantly, a measure of the respiratory function to determine whether measured differences in bioenergetic state are associated with a change in the energetic capacity of tissues that could feasibly affect future reproduction or lifespan. More careful consideration of the life-history context and bioenergetic variables will improve our understanding of the mechanisms that underlie the life-history patterns of animals.
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Affiliation(s)
- Yufeng Zhang
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Wendy R Hood
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
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8
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Hämäläinen A, Dammhahn M, Aujard F, Eberle M, Hardy I, Kappeler PM, Perret M, Schliehe-Diecks S, Kraus C. Senescence or selective disappearance? Age trajectories of body mass in wild and captive populations of a small-bodied primate. Proc Biol Sci 2015; 281:20140830. [PMID: 25100693 DOI: 10.1098/rspb.2014.0830] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Classic theories of ageing consider extrinsic mortality (EM) a major factor in shaping longevity and ageing, yet most studies of functional ageing focus on species with low EM. This bias may cause overestimation of the influence of senescent declines in performance over condition-dependent mortality on demographic processes across taxa. To simultaneously investigate the roles of functional senescence (FS) and intrinsic, extrinsic and condition-dependent mortality in a species with a high predation risk in nature, we compared age trajectories of body mass (BM) in wild and captive grey mouse lemurs (Microcebus murinus) using longitudinal data (853 individuals followed through adulthood). We found evidence of non-random mortality in both settings. In captivity, the oldest animals showed senescence in their ability to regain lost BM, whereas no evidence of FS was found in the wild. Overall, captive animals lived longer, but a reversed sex bias in lifespan was observed between wild and captive populations. We suggest that even moderately condition-dependent EM may lead to negligible FS in the wild. While high EM may act to reduce the average lifespan, this evolutionary process may be counteracted by the increased fitness of the long-lived, high-quality individuals.
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Affiliation(s)
- Anni Hämäläinen
- Department of Sociobiology/Anthropology, Georg-August University of Göttingen, Kellnerweg 6, Göttingen 37077, Germany Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany
| | - Melanie Dammhahn
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany Department of Animal Ecology, University of Potsdam, Maulbeerallee 1, Potsdam 14469, Germany
| | - Fabienne Aujard
- UMR 7179, CNRS & Muséum National d'Histoire Naturelle, 1 Avenue du Petit Château, Brunoy 91800, France
| | - Manfred Eberle
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany
| | - Isabelle Hardy
- UMR 7179, CNRS & Muséum National d'Histoire Naturelle, 1 Avenue du Petit Château, Brunoy 91800, France
| | - Peter M Kappeler
- Department of Sociobiology/Anthropology, Georg-August University of Göttingen, Kellnerweg 6, Göttingen 37077, Germany Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany
| | - Martine Perret
- UMR 7179, CNRS & Muséum National d'Histoire Naturelle, 1 Avenue du Petit Château, Brunoy 91800, France
| | - Susanne Schliehe-Diecks
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany
| | - Cornelia Kraus
- Department of Sociobiology/Anthropology, Georg-August University of Göttingen, Kellnerweg 6, Göttingen 37077, Germany Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, Göttingen 37077, Germany
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9
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Michel ES, Demarais S, Strickland BK, Belant JL. Contrasting the Effects of Maternal and Behavioral Characteristics on Fawn Birth Mass in White-Tailed Deer. PLoS One 2015; 10:e0136034. [PMID: 26288141 PMCID: PMC4546060 DOI: 10.1371/journal.pone.0136034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 07/29/2015] [Indexed: 11/18/2022] Open
Abstract
Maternal care influences offspring quality and can improve a mother's inclusive fitness. However, improved fitness may only occur when offspring quality (i.e., offspring birth mass) persists throughout life and enhances survival and/or reproductive success. Although maternal body mass, age, and social rank have been shown to influence offspring birth mass, the inter-dependence among these variables makes identifying causation problematic. We established that fawn birth mass was related to adult body mass for captive male and female white-tailed deer (Odocoileus virginianus), thus maternal care should improve offspring fitness. We then used path analysis to identify which maternal characteristic(s) most influenced fawn birth mass of captive female white-tailed deer. Maternal age, body mass and social rank had varying effects on fawn birth mass. Maternal body mass displayed the strongest direct effect on fawn birth mass, followed by maternal age and social rank. Maternal body mass had a greater effect on social rank than age. The direct path between social rank and fawn birth mass may indicate dominance as an underlying mechanism. Our results suggest that heavier mothers could use dominance to improve access to resources, resulting in increased fitness through production of heavier offspring.
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Affiliation(s)
- Eric S. Michel
- Department of Wildlife, Fisheries and Aquaculture, Forest and Wildlife Research Center, Deer Ecology and Management Laboratory, Mississippi State University, Mississippi State, Mississippi, United States of America
- * E-mail:
| | - Stephen Demarais
- Department of Wildlife, Fisheries and Aquaculture, Forest and Wildlife Research Center, Deer Ecology and Management Laboratory, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Bronson K. Strickland
- Department of Wildlife, Fisheries and Aquaculture, Forest and Wildlife Research Center, Deer Ecology and Management Laboratory, Mississippi State University, Mississippi State, Mississippi, United States of America
| | - Jerrold L. Belant
- Carnivore Ecology Laboratory, Forest and Wildlife Research Center, Mississippi State University, Mississippi State, Mississippi, United States of America
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10
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Barros CS, Püttker T, Pardini R. Timing and environmental cues associated with triggering of reproductive activity in Atlantic forest marsupials. Mamm Biol 2015. [DOI: 10.1016/j.mambio.2014.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Resource availability as a proxy for terminal investment in a beetle. Oecologia 2015; 178:339-45. [PMID: 25582868 DOI: 10.1007/s00442-014-3210-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 12/15/2014] [Indexed: 10/24/2022]
Abstract
Terminal investment hypothesis is a longstanding theoretical idea that organisms should increase their reproductive effort as their prospects for survival and reproduction decline. However, numerous attempts to test the terminal investment in reproduction have yielded contradictory results. This study reports an experimental confirmation of the terminal investment hypothesis. It was predicted that immune-challenged yellow mealworm beetles (Tenebrio molitor) are more likely to follow terminal investment strategy when their food resources are limited. Our results suggest the key role of food resources while making decisions to follow a terminal investment strategy. We found that male individuals invested in their sexual attractiveness at the expense of immune response and survival when food was not available. In contrast, the beetles did not decrease their lifespan and did not invest in the attractiveness of their sex odours under conditions of food ad libitum. Our results show the importance of food availability and quality in understanding the evolution of reproductive strategies.
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12
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Adler MI, Bonduriansky R. Sexual conflict, life span, and aging. Cold Spring Harb Perspect Biol 2014; 6:cshperspect.a017566. [PMID: 24938876 DOI: 10.1101/cshperspect.a017566] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The potential for sexual conflict to influence the evolution of life span and aging has been recognized for more than a decade, and recent work also suggests that variation in life span and aging can influence sexually antagonistic coevolution. However, empirical exploration of these ideas is only beginning. Here, we provide an overview of the ideas and evidence linking inter- and intralocus sexual conflicts with life span and aging. We aim to clarify the conceptual basis of this research program, examine the current state of knowledge, and suggest key questions for further investigation.
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Affiliation(s)
- Margo I Adler
- Evolution & Ecology Research Centre and School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, New South Wales, Australia
| | - Russell Bonduriansky
- Evolution & Ecology Research Centre and School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, New South Wales, Australia
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13
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Pardo D, Barbraud C, Weimerskirch H. What shall I do now? State-dependent variations of life-history traits with aging in Wandering Albatrosses. Ecol Evol 2014; 4:474-87. [PMID: 24634731 PMCID: PMC3936393 DOI: 10.1002/ece3.882] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 10/14/2013] [Accepted: 10/15/2013] [Indexed: 11/23/2022] Open
Abstract
Allocation decisions depend on an organism's condition which can change with age. Two opposite changes in life-history traits are predicted in the presence of senescence: either an increase in breeding performance in late age associated with terminal investment or a decrease due to either life-history trade-offs between current breeding and future survival or decreased efficiency at old age. Age variation in several life-history traits has been detected in a number of species, and demographic performances of individuals in a given year are influenced by their reproductive state the previous year. Few studies have, however, examined state-dependent variation in life-history traits with aging, and they focused mainly on a dichotomy of successful versus failed breeding and non-breeding birds. Using a 50-year dataset on the long-lived quasi-biennial breeding wandering albatross, we investigated variations in life-history traits with aging according to a gradient of states corresponding to potential costs of reproduction the previous year (in ascending order): non-breeding birds staying at sea or present at breeding grounds, breeding birds that failed early, late or were successful. We used multistate models to study survival and decompose reproduction into four components (probabilities of return, breeding, hatching, and fledging), while accounting for imperfect detection. Our results suggest the possible existence of two strategies in the population: strict biennial breeders that exhibited almost no reproductive senescence and quasi-biennial breeders that showed an increased breeding frequency with a strong and moderate senescence on hatching and fledging probabilities, respectively. The patterns observed on survival were contrary to our predictions, suggesting an influence of individual quality rather than trade-offs between reproduction and survival at late ages. This work represents a step further into understanding the evolutionary ecology of senescence and its relationship with costs of reproduction at the population level. It paves the way for individual-based studies that could show the importance of intra-population heterogeneity in those processes.
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Affiliation(s)
- Deborah Pardo
- CEBC-CNRS UPR 1934 F 79360, Villiers-en-Bois, France
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14
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Javoiš J. A two-resource model of terminal investment. Theory Biosci 2013; 132:123-32. [PMID: 23408007 DOI: 10.1007/s12064-013-0176-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 01/24/2013] [Indexed: 11/26/2022]
Abstract
The most widely known theoretical basis for the hypothesis of terminal investment is the classic model by George C. Williams (1966). Although this model predicts that reproductive effort (i.e. the proportion of available resources devoted to reproduction) increases with decreasing reproductive value, it implies that reproductive allocation in absolute terms should remain stable. This contrasts with the empirical evidence on terminal investment reported to date: the vast majority of positive case studies report an increase in some aspect of reproductive allocation in absolute terms. Also, a substantial number of studies have failed to record terminal investment, despite expectations. Here, I present a simple conceptual model which explains such results. I argue that to explain terminal investment, an organism's reproductive capacity must not be considered as a common pool of resources (often described by the term 'reproductive value'), but as a set of different resources which are not easily convertible to each other, and should be exhausted in balance. Thus, if one resource accidentally decreases, in response, the others must be expended at higher rate. To test this model, each reproductive allocation should be measured in a more specific currency (or currencies) than traditional 'reproductive effort'. The model is consistent with both the positive and the negative case reports on terminal investment.
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Affiliation(s)
- Juhan Javoiš
- Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia.
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Contest behavior and other reproductive efforts in aging breeders: a test of residual reproductive value and state-dependent models. Behav Ecol Sociobiol 2012. [DOI: 10.1007/s00265-012-1406-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Ligout S, Munier D, Marquereau L, Greenfield MD. Chronological vs. Physiological Age as Determinants of Mating Decisions: Studies on Female Choice Over Lifespan in An Acoustic Moth. Ethology 2012. [DOI: 10.1111/j.1439-0310.2012.02064.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Séverine Ligout
- Institut de recherche sur la biologie de l'insecte (IRBI), CNRS UMR 7261; Université François Rabelais de Tours; Tours; France
| | - Damien Munier
- Institut de recherche sur la biologie de l'insecte (IRBI), CNRS UMR 7261; Université François Rabelais de Tours; Tours; France
| | - Lucie Marquereau
- Institut de recherche sur la biologie de l'insecte (IRBI), CNRS UMR 7261; Université François Rabelais de Tours; Tours; France
| | - Michael D. Greenfield
- Institut de recherche sur la biologie de l'insecte (IRBI), CNRS UMR 7261; Université François Rabelais de Tours; Tours; France
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17
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Mauck RA, Huntington CE, Doherty Jr PF. Experience versus effort: what explains dynamic heterogeneity with respect to age? OIKOS 2012. [DOI: 10.1111/j.1600-0706.2012.20271.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Schwanz LE, Robert KA. Reproductive ecology of wild tammar wallabies in natural and developed habitats on Garden Island, Western Australia. AUST J ZOOL 2012. [DOI: 10.1071/zo12024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Reproduction may be influenced by major environmental changes experienced by an entire population as well as variation within a population in maternal resource availability or quality. We examined relationships between body condition and reproductive traits in two wild populations of the seasonally breeding tammar wallaby (Macropus eugenii) on Garden Island, Western Australia, that differed in access to supplemental food resources. Body condition changed predictably over the year, with females losing condition over the dry summer and gaining condition over the winters, when lactation occurs and most annual precipitation falls. Body condition influenced reproduction, with females of greater body condition more likely to have a pouch young, and to have a larger pouch young, early in the reproductive season. This intrapopulation pattern was opposite to that seen across populations – females in a native bushland were in poorer condition yet were more likely to have pouch young, and had larger pouch young, in March than did females living in a water-supplemented habitat on a naval base. Body condition did not influence the probability of weaning a pouch young in a year, nor did reproductive success influence changes in body condition across seasons. Instead, annual variation in precipitation had a dramatic effect on population weaning success in the native bushland, but not on the naval base. In summary, individual variation in body condition as well as large climatic variation influenced the reproduction of tammar wallabies on Garden Island, but the nature of the effect depended on the different habitats experienced by the two study populations.
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Mason THE, Chirichella R, Richards SA, Stephens PA, Willis SG, Apollonio M. Contrasting life histories in neighbouring populations of a large mammal. PLoS One 2011; 6:e28002. [PMID: 22125651 PMCID: PMC3220718 DOI: 10.1371/journal.pone.0028002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 10/30/2011] [Indexed: 11/18/2022] Open
Abstract
Background A fundamental life history question is how individuals should allocate resources to reproduction optimally over time (reproductive allocation). The reproductive restraint hypothesis predicts that reproductive effort (RE; the allocation of resources to current reproduction) should peak at prime-age, whilst the terminal investment hypothesis predicts that individuals should continue to invest more resources in reproduction throughout life, owing to an ever-decreasing residual reproductive value. There is evidence supporting both hypotheses in the scientific literature. Methodology/Principal Findings We used an uncommonly large, 38 year dataset on Alpine chamois (Rupicapra rupicapra) shot at various times during the rutting period to test these two hypotheses. We assumed that body mass loss in rutting males was strongly related to RE and, using a process-based approach, modelled how male relative mass loss rates varied with age. For different regions of our study area, we provide evidence consistent with different hypotheses for reproductive allocation. In sites where RE declined in older age, this appears to be strongly linked to declining body condition in old males. In this species, terminal investment may only occur in areas with lower rates of body mass senescence. Conclusions/Significance Our results show that patterns of reproductive allocation may be more plastic than previously thought. It appears that there is a continuum from downturns in RE at old age to terminal investment that can be manifest, even across adjacent populations. Our work identifies uncertainty in the relationship between reproductive restraint and a lack of competitive ability in older life (driven by body mass senescence); both could explain a decline in RE in old age and may be hard to disentangle in empirical data. We discuss a number of environmental and anthropogenic factors which could influence reproductive life histories, underlining that life history patterns should not be generalised across different populations.
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Affiliation(s)
- Tom H E Mason
- School of Biological and Biomedical Sciences, University of Durham, Durham, County Durham, United Kingdom.
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20
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Nielsen ML, Holman L. Terminal investment in multiple sexual signals: immune-challenged males produce more attractive pheromones. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01914.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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21
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PRICE-REES SAMANTHAJ, CONGDON BRADLEYC, KROCKENBERGER ANDREWK. Size delays female senescence in a medium sized marsupial: The effects of maternal traits on annual fecundity in the northern brown bandicoot (Isoodon macrourus). AUSTRAL ECOL 2011. [DOI: 10.1111/j.1442-9993.2011.02279.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Ceballos S, Kiørboe T. Senescence and sexual selection in a pelagic copepod. PLoS One 2011; 6:e18870. [PMID: 21533149 PMCID: PMC3077418 DOI: 10.1371/journal.pone.0018870] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 03/18/2011] [Indexed: 11/19/2022] Open
Abstract
The ecology of senescence in marine zooplankton is not well known. Here we demonstrate senescence effects in the marine copepod Oithona davisae and show how sex and sexual selection accelerate the rate of ageing in the males. We show that adult mortality increases and male mating capacity and female fertility decrease with age and that the deterioration in reproductive performance is faster for males. Males have a limited mating capacity because they can fertilize < 2 females day(-1) and their reproductive life span is 10 days on average. High female encounter rates in nature (>10 day(-1)), a rapid age-dependent decline in female fertility, and a high mortality cost of mating in males are conducive to the development of male choosiness. In our experiments males in fact show a preference for mating with young females that are 3 times more fertile than 30-day old females. We argue that this may lead to severe male-male competition for young virgin females and a trade-off that favours investment in mate finding over maintenance. In nature, mate finding leads to a further elevated mortality of males, because these swim rapidly in their search for attractive partners, further relaxing fitness benefits of maintenance investments. We show that females have a short reproductive period compared to their average longevity but virgin females stay fertile for most of their life. We interpret this as an adaptation to a shortage of males, because a long life increases the chance of fertilization and/or of finding a high quality partner. The very long post reproductive life that many females experience is thus a secondary effect of such an adaptation.
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Affiliation(s)
- Sara Ceballos
- National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund, Denmark
| | - Thomas Kiørboe
- National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund, Denmark
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Fisher DO, Blomberg SP. Costs of reproduction and terminal investment by females in a semelparous marsupial. PLoS One 2011; 6:e15226. [PMID: 21249185 PMCID: PMC3020937 DOI: 10.1371/journal.pone.0015226] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Accepted: 11/01/2010] [Indexed: 11/19/2022] Open
Abstract
Evolutionary explanations for life history diversity are based on the idea of costs of reproduction, particularly on the concept of a trade-off between age-specific reproduction and parental survival, and between expenditure on current and future offspring. Such trade-offs are often difficult to detect in population studies of wild mammals. Terminal investment theory predicts that reproductive effort by older parents should increase, because individual offspring become more valuable to parents as the conflict between current versus potential future offspring declines with age. In order to demonstrate this phenomenon in females, there must be an increase in maternal expenditure on offspring with age, imposing a fitness cost on the mother. Clear evidence of both the expenditure and fitness cost components has rarely been found. In this study, we quantify costs of reproduction throughout the lifespan of female antechinuses. Antechinuses are nocturnal, insectivorous, forest-dwelling small (20–40 g) marsupials, which nest in tree hollows. They have a single synchronized mating season of around three weeks, which occurs on predictable dates each year in a population. Females produce only one litter per year. Unlike almost all other mammals, all males, and in the smaller species, most females are semelparous. We show that increased allocation to current reproduction reduces maternal survival, and that offspring growth and survival in the first breeding season is traded-off with performance of the second litter in iteroparous females. In iteroparous females, increased allocation to second litters is associated with severe weight loss in late lactation and post-lactation death of mothers, but increased offspring growth in late lactation and survival to weaning. These findings are consistent with terminal investment. Iteroparity did not increase lifetime reproductive success, indicating that terminal investment in the first breeding season at the expense of maternal survival (i.e. semelparity) is likely to be advantageous for females.
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Affiliation(s)
- Diana O Fisher
- School of Biological Sciences, The University of Queensland, St. Lucia, Australia.
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24
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Goutte A, Antoine É, Chastel O. Experimentally delayed hatching triggers a magnified stress response in a long-lived bird. Horm Behav 2011; 59:167-73. [PMID: 21087608 DOI: 10.1016/j.yhbeh.2010.11.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 11/03/2010] [Accepted: 11/07/2010] [Indexed: 11/28/2022]
Abstract
In birds, the timing of breeding is a key life-history trait with crucial fitness consequences. We predicted that parents may value a brood less if it hatched later than expected, thereby decreasing their parental effort. In addition, breeding effort would be further modulated by the age-specific decline of future breeding opportunities. We experimentally investigated whether snow petrels, Pagodroma nivea, were less committed to care for a chick that hatched later than expected. The timing of hatching was manipulated by swapping eggs between early and late known-age pairs (7-44 years old), and investigations on hormonal and behavioral adjustments were conducted. As a hormonal gauge of parental commitment to the brood, we measured the corticosterone stress response of guarding adults. Indeed, an acute stress response mediates energy allocation towards survival at the expense of current reproduction and is magnified when the current brood value is low, as it is expected to be in young and/or delayed parents. As predicted, egg desertion and the magnitude of the stress response was stronger in delayed pairs compared to control ones. However, the treatment did not decrease the length of the guarding period, chick condition and chick survival. In addition, old parents resisted stress better (lower stress-induced corticosterone levels) than young ones. Our study provides evidence that snow petrels, as prudent parents, may value a brood less if it hatched later than expected. Thus, in long-lived birds, the responsiveness to stressors appeared to be adjusted according to the individual prospect of future breeding opportunities (age) and to the current brood value (timing of breeding).
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Affiliation(s)
- Aurélie Goutte
- Centre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, F-79360 Villiers en Bois, France.
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Lafaille M, Bimbard G, Greenfield MD. Risk trading in mating behavior: forgoing anti-predator responses reduces the likelihood of missing terminal mating opportunities. Behav Ecol Sociobiol 2010. [DOI: 10.1007/s00265-010-0963-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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McNamara JM, Houston AI, Barta Z, Scheuerlein A, Fromhage L. Deterioration, death and the evolution of reproductive restraint in late life. Proc Biol Sci 2009; 276:4061-4066. [PMID: 19726476 PMCID: PMC2825774 DOI: 10.1098/rspb.2009.0959] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 08/10/2009] [Indexed: 08/17/2023] Open
Abstract
Explaining why organisms schedule reproduction over their lifetimes in the various ways that they do is an enduring challenge in biology. An influential theoretical prediction states that organisms should increasingly invest in reproduction as they approach the end of their life. An apparent mismatch of empirical data with this prediction has been attributed to age-related constraints on the ability to reproduce. Here we present a general framework for the evolution of age-related reproductive trajectories. Instead of characterizing an organism by its age, we characterize it by its physiological condition. We develop a common currency that if maximized at each time guarantees the whole life history is optimal. This currency integrates reproduction, mortality and changes in condition. We predict that under broad conditions it will be optimal for organisms to invest less in reproduction as they age, thus challenging traditional interpretations of age-related traits and renewing debate about the extent to which observed life histories are shaped by constraint versus adaptation. Our analysis gives a striking illustration of the differences between an age-based and a condition-based approach to life-history theory. It also provides a unified account of not only standard life-history models but of related models involving the allocation of limited resources.
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Affiliation(s)
- John M. McNamara
- Department of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, UK
| | - Alasdair I. Houston
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
| | - Zoltan Barta
- Department of Evolutionary Zoology, University of Debrecen, Debrecen H-4010, Hungary
| | - Alexander Scheuerlein
- Max Planck Institute for Demographic Research, Konrad-Zuse-Strasse 1, Rostock D-18057, Germany
| | - Lutz Fromhage
- Zoological Institute and Museum, Martin-Luther-King Platz 3, 20146Hamburg, Germany
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28
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Trumbo ST. Age-related reproductive performance in the parental burying beetle, Nicrophorus orbicollis. Behav Ecol 2009. [DOI: 10.1093/beheco/arp082] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Bercovitch FB, Loomis CP, Rieches RG. Age-Specific Changes in Reproductive Effort and Terminal Investment in Female Nile Lechwe. J Mammal 2009. [DOI: 10.1644/08-mamm-a-124.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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30
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Isaac JL. Sexual dimorphism in a marsupial: seasonal and lifetime differences in sex-specific mass. AUST J ZOOL 2006. [DOI: 10.1071/zo05060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Whereas sexual dimorphism in body mass is common in many vertebrates, the developmental mechanisms leading to diverging growth patterns between the sexes are poorly understood in mammals. In the present study, I investigate seasonal and lifetime differences in sex-specific mass in a marsupial, the common brushtail possum (Trichosurus vulpecula). From the age of 2 years, males were heavier than females, but significant dimorphism was evident only at the age of 4 years. Annual mass gain was greater in males than in females from 2 to 4 years of age. The body mass of both sexes fluctuated throughout the year, although patterns differed: females lost mass during lactation in winter, whereas males lost mass during the breeding season in later summer and autumn. The mass of a juvenile predicted its mass as an adult for males, but not females. Male-biased sexual dimorphism in mass of possums appears to arise through a combination of a greater rate and duration of mass gain in young males, and the diversion of somatic reserves away from growth and into reproduction in females.
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