1
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Duxbury EML, Carlsson H, Kimberley A, Ridge Y, Johnson K, Maklakov AA. Reduced insulin/IGF-1 signalling upregulates two anti-viral immune pathways, decreases viral load and increases survival under viral infection in C. elegans. GeroScience 2024:10.1007/s11357-024-01147-7. [PMID: 38589671 DOI: 10.1007/s11357-024-01147-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 03/25/2024] [Indexed: 04/10/2024] Open
Abstract
Reduced insulin/IGF-1 signalling (rIIS) improves survival across diverse taxa and there is a growing interest in its role in regulating immune function. Whilst rIIS can improve anti-bacterial resistance, the consequences for anti-viral immunity are yet to be systematically examined. Here, we show that rIIS in adult Caenorhabditis elegans increases the expression of key genes in two different anti-viral immunity pathways, whilst reducing viral load in old age, increasing survival and reducing rate-of-senescence under infection by naturally occurring positive-sense single-stranded RNA Orsay virus. We found that both drh-1 in the anti-viral RNA interference (RNAi) pathway and cde-1 in the terminal uridylation-based degradation of viral RNA pathway were upregulated in early adulthood under rIIS and increased anti-viral resistance was not associated with reproductive costs. Remarkably, rIIS increased anti-viral gene expression only in infected worms, potentially to curb the costs of constitutively upregulated immunity. RNA viruses are found across taxa from plants to mammals and we demonstrate a novel role for rIIS in regulating resistance to viral infection. We therefore highlight this evolutionarily conserved signalling pathway as a promising therapeutic target to improve anti-viral immunity.
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Affiliation(s)
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Annabel Kimberley
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Yvonne Ridge
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Katie Johnson
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, UK
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2
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Lemaître JF, Moorad J, Gaillard JM, Maklakov AA, Nussey DH. A unified framework for evolutionary genetic and physiological theories of aging. PLoS Biol 2024; 22:e3002513. [PMID: 38412150 PMCID: PMC10898761 DOI: 10.1371/journal.pbio.3002513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024] Open
Abstract
Why and how we age are 2 intertwined questions that have fascinated scientists for many decades. However, attempts to answer these questions remain compartmentalized, preventing a comprehensive understanding of the aging process. We argue that the current lack of knowledge about the evolution of aging mechanisms is due to a lack of clarity regarding evolutionary theories of aging that explicitly involve physiological processes: the disposable soma theory (DST) and the developmental theory of aging (DTA). In this Essay, we propose a new hierarchical model linking genes to vital rates, enabling us to critically reevaluate the DST and DTA in terms of their relationship to evolutionary genetic theories of aging (mutation accumulation (MA) and antagonistic pleiotropy (AP)). We also demonstrate how these 2 theories can be incorporated in a unified hierarchical framework. The new framework will help to generate testable hypotheses of how the hallmarks of aging are shaped by natural selection.
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Affiliation(s)
- Jean-François Lemaître
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, Villeurbanne, France
| | - Jacob Moorad
- Institute of Ecology & Evolution, School of Biological Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Jean-Michel Gaillard
- Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, Villeurbanne, France
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Daniel H. Nussey
- Institute of Ecology & Evolution, School of Biological Science, University of Edinburgh, Edinburgh, United Kingdom
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3
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Chen HY, Krieg T, Mautz B, Jolly C, Scofield D, Maklakov AA, Immler S. Germline mutation rate is elevated in young and old parents in Caenorhabditis remanei. Evol Lett 2023; 7:478-489. [PMID: 38045724 PMCID: PMC10692996 DOI: 10.1093/evlett/qrad052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 09/19/2023] [Accepted: 10/06/2023] [Indexed: 12/05/2023] Open
Abstract
The effect of parental age on germline mutation rate across generations is not fully understood. While some studies report a positive linear relationship of mutation rate with increasing age, others suggest that mutation rate varies with age but not in a linear fashion. We investigated the effect of parental age on germline mutations by generating replicated mutation accumulation lines in Caenorhabditis remanei at three parental ages ("Young T1" [Day 1], "Peak T2" [Day 2], and "Old T5" [Day 5] parents). We conducted whole-genome resequencing and variant calling to compare differences in mutation rates after three generations of mutation accumulation. We found that Peak T2 lines had an overall reduced mutation rate compared to Young T1 and Old T5 lines, but this pattern of the effect varied depending on the variant impact. Specifically, we found no high-impact variants in Peak T2 lines, and modifiers and up- and downstream gene variants were less frequent in these lines. These results suggest that animals at the peak of reproduction have better DNA maintenance and repair compared to young and old animals. We propose that C. remanei start to reproduce before they optimize their DNA maintenance and repair, trading the benefits of earlier onset of reproduction against offspring mutation load. The increase in offspring mutation load with age likely represents germline senescence.
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Affiliation(s)
- Hwei-yen Chen
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- Department of Biology, Lund University, Lund, Sweden
| | - Therese Krieg
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Brian Mautz
- Department of Medicine, Division of Epidemiology, Vanderbilt University, Nashville, United States
| | - Cécile Jolly
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | - Douglas Scofield
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Simone Immler
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
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4
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Rostant WG, Mason JS, West N, Maklakov AA, Chapman T. Sociosexual Exposure Has Opposing Effects on Male and Female Actuarial Senescence in the Fruit Fly Drosophila melanogaster. J Gerontol A Biol Sci Med Sci 2023; 78:2230-2239. [PMID: 37694551 PMCID: PMC10692434 DOI: 10.1093/gerona/glad215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Indexed: 09/12/2023] Open
Abstract
Males and females rarely express the same length of life. Here, we studied how sociosexual exposure shapes male and female age-specific mortality rates in Drosophila melanogaster. We maintained focal females and males within large, replicated cohorts throughout life with individuals of the same or opposite sex. Consistent with previous works, we found that females kept throughout their lives with males had only half the lifespan of those maintained throughout life at the same density in same-sex cohorts. In contrast, only a small lifespan decrease was observed in the corresponding male treatments and the reduction in male lifespan following exposure throughout life to other males or females was similar. Deconvolution of underlying aging parameters revealed that changes in lifespan were underpinned by opposing effects on actuarial aging in males versus females. Exposure to the opposite or same sex increased initial mortality rate in both sexes. However, in females, increasing exposure to males increased the rate of aging, while increasing exposure to females actually decreased it. The effects were in the opposite direction in males and were much smaller in magnitude. Overall, the findings were consistent with reports suggesting that exposure to the same versus opposite sex can affect survival differently in males and females. However, they also reveal a new insight-that overall lifespan can be underpinned by key differences in actuarial senescence in each sex. The findings suggest that responses to same or opposite sex exposure may have fundamentally and qualitatively different physiological consequences for health in males and females.
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Affiliation(s)
- Wayne G Rostant
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Janet S Mason
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Nicholas West
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich, UK
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5
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Ivimey-Cook ER, Murray DS, de Coriolis JC, Edden N, Immler S, Maklakov AA. Correction to: 'Fasting increases investment in soma upon refeeding at the cost of gamete quality in zebrafish' (2023) by Ivimey-Cook et al.. Proc Biol Sci 2023; 290:20230872. [PMID: 37132242 PMCID: PMC10154932 DOI: 10.1098/rspb.2023.0872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023] Open
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6
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Ivimey-Cook ER, Murray DS, de Coriolis JC, Edden N, Immler S, Maklakov AA. Fasting increases investment in soma upon refeeding at the cost of gamete quality in zebrafish. Proc Biol Sci 2023; 290:20221556. [PMID: 37040805 PMCID: PMC10089719 DOI: 10.1098/rspb.2022.1556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023] Open
Abstract
Fasting increases lifespan in invertebrates, improves biomarkers of health in vertebrates and is increasingly proposed as a promising route to improve human health. Nevertheless, little is known about how fasted animals use resources upon refeeding, and how such decisions affect putative trade-offs between somatic growth and repair, reproduction and gamete quality. Such fasting-induced trade-offs are based on strong theoretical foundations and have been recently discovered in invertebrates, but the data on vertebrates are lacking. Here, we report that fasted female zebrafish, Danio rerio, increase investment in soma upon refeeding, but it comes at a cost of egg quality. Specifically, an increase in fin regrowth was accompanied by a reduction in 24 h post-fertilization offspring survival. Refed males showed a reduction in sperm velocity and impaired 24 h post-fertilization offspring survival. These findings underscore the necessity of considering the impact on reproduction when assessing evolutionary and biomedical implications of lifespan-extending treatments in females and males and call for careful evaluation of the effects of intermittent fasting on fertilization.
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Affiliation(s)
- Edward R Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norfolk NR4 7TJ, UK
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - David S Murray
- Collaborative Centre for Sustainable Use of the Seas (CCSUS), School of Environmental Sciences, University of East Anglia, Norfolk NR4 7TJ, UK
- The Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft, Suffolk NR33 0HT, UK
| | | | - Nathan Edden
- School of Biological Sciences, University of East Anglia, Norfolk NR4 7TJ, UK
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norfolk NR4 7TJ, UK
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norfolk NR4 7TJ, UK
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7
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Duxbury EML, Carlsson H, Sales K, Sultanova Z, Immler S, Chapman T, Maklakov AA. Multigenerational downregulation of insulin/IGF-1 signaling in adulthood improves lineage survival, reproduction, and fitness in Caenorhabditis elegans supporting the developmental theory of ageing. Evolution 2022; 76:2829-2845. [PMID: 36199198 PMCID: PMC10092551 DOI: 10.1111/evo.14640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/18/2022] [Accepted: 09/08/2022] [Indexed: 01/22/2023]
Abstract
Adulthood-only downregulation of insulin/IGF-1 signaling (IIS), an evolutionarily conserved pathway regulating resource allocation between somatic maintenance and reproduction, increases life span without fecundity cost in the nematode, Caenorhabditis elegans. However, long-term multigenerational effects of reduced IIS remain unexplored and are proposed to carry costs for offspring quality. To test this hypothesis, we ran a mutation accumulation (MA) experiment and downregulated IIS in half of the 400 MA lines by silencing daf-2 gene expression using RNA interference (RNAi) across 40 generations. Contrary to the prediction, adulthood-only daf-2 RNAi reduced extinction of MA lines both under UV-induced and spontaneous MA. Fitness of the surviving UV-induced MA lines was higher under daf-2 RNAi. Reduced IIS increased intergenerational F1 offspring fitness under UV stress but had no quantifiable transgenerational effects. Functional hrde-1 was required for the benefits of multigenerational daf-2 RNAi. Overall, we found net benefit to fitness from multigenerational reduction of IIS and the benefits became more apparent under stress. Because reduced daf-2 expression during development carries fitness costs, we suggest that our findings are best explained by the developmental theory of ageing, which maintains that the decline in the force of selection with age results in poorly regulated gene expression in adulthood.
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Affiliation(s)
- Elizabeth M L Duxbury
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Kris Sales
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Zahida Sultanova
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
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8
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Abstract
Dietary restriction (DR) improves survival across a wide range of taxa yet remains poorly understood. The key unresolved question is whether this evolutionarily conserved response to temporary lack of food is adaptive. Recent work suggests that early-life DR reduces survival and reproduction when nutrients subsequently become plentiful, thereby challenging adaptive explanations. A new hypothesis maintains that increased survival under DR results from reduced costs of overfeeding. We tested the adaptive value of DR response in an outbred population of Drosophila melanogaster fruit flies. We found that DR females did not suffer from reduced survival upon subsequent re-feeding and had increased reproduction and mating success compared to their continuously fully fed (FF) counterparts. The increase in post-DR reproductive performance was of sufficient magnitude that females experiencing early-life DR had the same total fecundity as continuously FF individuals. Our results suggest that the DR response is adaptive and increases fitness when temporary food shortages cease.
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Affiliation(s)
- Zahida Sultanova
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Edward R. Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
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9
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Abstract
Old parental age is commonly associated with negative effects on offspring life-history traits. Such parental senescence effects are predicted to have a cumulative detrimental effect over successive generations. However, old parents may benefit from producing higher quality offspring when these compete for seasonal resources. Thus, old parents may choose to increase investment in their offspring, thereby producing fewer but larger and more competitive progeny. We show that Caenorhabditis elegans hermaphrodites increase parental investment with advancing age, resulting in fitter offspring who reach their reproductive peak earlier. Remarkably, these effects increased over six successive generations of breeding from old parents and were subsequently reversed following a single generation of breeding from a young parent. Our findings support the hypothesis that offspring of old parents receive more resources and convert them into increasingly faster life histories. These results contradict the theory that old parents transfer a cumulative detrimental 'ageing factor' to their offspring.
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Affiliation(s)
- Laura M Travers
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen 18D, 75236 Uppsala, Sweden
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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10
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Carlsson H, Ivimey-Cook E, Duxbury EML, Edden N, Sales K, Maklakov AA. Ageing as "early-life inertia": Disentangling life-history trade-offs along a lifetime of an individual. Evol Lett 2021; 5:551-564. [PMID: 34621540 PMCID: PMC8484722 DOI: 10.1002/evl3.254] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/19/2021] [Accepted: 08/13/2021] [Indexed: 11/10/2022] Open
Abstract
The theory that ageing evolves because of competitive resource allocation between the soma and the germline has been challenged by studies showing that somatic maintenance can be improved without impairing reproduction. However, it has been suggested that cost‐free improvement in somatic maintenance is possible only under a narrow range of benign conditions. Here, we show that experimental downregulation of insulin/IGF‐1 signaling (IIS) in C. elegans nematodes, a robustly reproducible life span‐ and health span‐extending treatment, reduces fitness in a complex variable environment when initiated during development but does not reduce fitness when initiated in adulthood. Thus, our results show that the costs and benefits of reduced IIS can be uncoupled when organisms inhabit variable environments, and, therefore, do not provide support for the resource allocation theory. Our findings support the theory that the force of natural selection on gene expression in evolutionarily conserved signaling pathways that shape life‐history traits declines after the onset of reproduction resulting in organismal senescence.
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Affiliation(s)
- Hanne Carlsson
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Edward Ivimey-Cook
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Elizabeth M L Duxbury
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Nathan Edden
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Kris Sales
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Alexei A Maklakov
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
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11
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Ivimey-Cook E, Bricout S, Candela V, Maklakov AA, Berg EC. Inbreeding reduces fitness of seed beetles under thermal stress. J Evol Biol 2021; 34:1386-1396. [PMID: 34233049 PMCID: PMC9291971 DOI: 10.1111/jeb.13899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/22/2021] [Accepted: 06/27/2021] [Indexed: 11/29/2022]
Abstract
Human‐induced environmental change can influence populations both at the global level through climatic warming and at the local level through habitat fragmentation. As populations become more isolated, they can suffer from high levels of inbreeding, which contributes to a reduction in fitness, termed inbreeding depression. However, it is still unclear if this increase in homozygosity also results in a corresponding increase in sensitivity to stressful conditions, which could intensify the already detrimental effects of environmental warming. Here, in a fully factorial design, we assessed the life‐long impact of increased inbreeding load and elevated temperature on key life history traits in the seed beetle, Callosobruchus maculatus. We found that beetles raised at higher temperatures had far reduced fitness and survival than beetles from control temperatures. Importantly, these negative effects were exacerbated in inbred beetles as a result of increased inbreeding load, with further detrimental effects manifesting on individual eclosion probability and lifetime reproductive success. These results reveal the harmful impact that increasing temperature and likelihood of habitat fragmentation due to anthropogenetic changes in environmental conditions could have on populations of organisms worldwide.
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Affiliation(s)
- Edward Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Sophie Bricout
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - Victoria Candela
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - Elena C Berg
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
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12
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Ivimey-Cook ER, Sales K, Carlsson H, Immler S, Chapman T, Maklakov AA. Transgenerational fitness effects of lifespan extension by dietary restriction in Caenorhabditis elegans. Proc Biol Sci 2021; 288:20210701. [PMID: 33975472 PMCID: PMC8113902 DOI: 10.1098/rspb.2021.0701] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 04/15/2021] [Indexed: 12/28/2022] Open
Abstract
Dietary restriction (DR) increases lifespan in a broad variety of organisms and improves health in humans. However, long-term transgenerational consequences of dietary interventions are poorly understood. Here, we investigated the effect of DR by temporary fasting (TF) on mortality risk, age-specific reproduction and fitness across three generations of descendants in Caenorhabditis elegans. We show that while TF robustly reduces mortality risk and improves late-life reproduction of the individuals subject to TF (P0), it has a wide range of both positive and negative effects on their descendants (F1-F3). Remarkably, great-grandparental exposure to TF in early life reduces fitness and increases mortality risk of F3 descendants to such an extent that TF no longer promotes a lifespan extension. These findings reveal that transgenerational trade-offs accompany the instant benefits of DR, underscoring the need to consider fitness of future generations in pursuit of healthy ageing.
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Affiliation(s)
- Edward R. Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Kris Sales
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK
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13
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Lind MI, Carlsson H, Duxbury EML, Ivimey-Cook E, Maklakov AA. Cost-free lifespan extension via optimization of gene expression in adulthood aligns with the developmental theory of ageing. Proc Biol Sci 2021; 288:20201728. [PMID: 33529563 PMCID: PMC7893226 DOI: 10.1098/rspb.2020.1728] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/11/2021] [Indexed: 01/11/2023] Open
Abstract
Ageing evolves because the force of selection on traits declines with age but the proximate causes of ageing are incompletely understood. The 'disposable soma' theory of ageing (DST) upholds that competitive resource allocation between reproduction and somatic maintenance underpins the evolution of ageing and lifespan. In contrast, the developmental theory of ageing (DTA) suggests that organismal senescence is caused by suboptimal gene expression in adulthood. While the DST predicts the trade-off between reproduction and lifespan, the DTA predicts that age-specific optimization of gene expression can increase lifespan without reproduction costs. Here we investigated the consequences for lifespan, reproduction, egg size and individual fitness of early-life, adulthood and post-reproductive onset of RNAi knockdown of five 'longevity' genes involved in key biological processes in Caenorhabditis elegans. Downregulation of these genes in adulthood and/or during post-reproductive period increases lifespan, while we found limited evidence for a link between impaired reproduction and extended lifespan. Our findings demonstrate that suboptimal gene expression in adulthood often contributes to reduced lifespan directly rather than through competitive resource allocation between reproduction and somatic maintenance. Therefore, age-specific optimization of gene expression in evolutionarily conserved signalling pathways that regulate organismal life histories can increase lifespan without fitness costs.
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Affiliation(s)
- Martin I. Lind
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Uppsala, SE-75236, Sweden
| | - Hanne Carlsson
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Edward Ivimey-Cook
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Alexei A. Maklakov
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
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14
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Mautz BS, Lind MI, Maklakov AA. Dietary Restriction Improves Fitness of Aging Parents But Reduces Fitness of Their Offspring in Nematodes. J Gerontol A Biol Sci Med Sci 2021; 75:843-848. [PMID: 31761926 PMCID: PMC7164528 DOI: 10.1093/gerona/glz276] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Indexed: 11/14/2022] Open
Abstract
Dietary restriction (DR) is a well-established intervention to extend lifespan across taxa. Recent studies suggest that DR-driven lifespan extension can be cost-free, calling into question a central tenant of the evolutionary theory of aging. Nevertheless, boosting parental longevity can reduce offspring fitness. Such intergenerational trade-offs are often ignored but can account for the "missing costs" of longevity. Here, we use the nematode Caenorhabditis remanei to test for effects of DR by fasting on fitness of females and their offspring. Females deprived of food for 6 days indeed had increased fecundity, survival, and stress resistance after re-exposure to food compared with their counterparts with constant food access. However, offspring of DR mothers had reduced early and lifetime fecundity, slower growth rate, and smaller body size at sexual maturity. These findings support the direct trade-off between investment in soma and gametes challenging the hypothesis that increased somatic maintenance and impaired reproduction can be decoupled.
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Affiliation(s)
- Brian S Mautz
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,Department of Medicine, Division of Epidemiology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvägen, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norfolk, UK
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15
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Jiménez-Ortega D, Kolm N, Immler S, Maklakov AA, Gonzalez-Voyer A. Long life evolves in large-brained bird lineages. Evolution 2020; 74:2617-2628. [PMID: 32840865 DOI: 10.1111/evo.14087] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 08/15/2020] [Accepted: 08/18/2020] [Indexed: 01/05/2023]
Abstract
The brain is an energetically costly organ that consumes a disproportionate amount of resources. Species with larger brains relative to their body size have slower life histories, with reduced output per reproductive event and delayed development times that can be offset by increasing behavioral flexibility. The "cognitive buffer" hypothesis maintains that large brain size decreases extrinsic mortality due to greater behavioral flexibility, leading to a longer lifespan. Alternatively, slow life histories, and long lifespan can be a pre-adaptation for the evolution of larger brains. Here, we use phylogenetic path analysis to contrast different evolutionary scenarios and disentangle direct and indirect relationships between brain size, body size, life history, and longevity across 339 altricial and precocial bird species. Our results support both a direct causal link between brain size and lifespan, and an indirect effect via other life history traits. These results indicate that large brain size engenders longer life, as proposed by the "cognitive buffer" hypothesis.
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Affiliation(s)
- Dante Jiménez-Ortega
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México.,Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Niclas Kolm
- Zoology Department, Stockholm University, Stockholm, Sweden
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
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16
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Monaghan P, Maklakov AA, Metcalfe NB. Intergenerational Transfer of Ageing: Parental Age and Offspring Lifespan. Trends Ecol Evol 2020; 35:927-937. [PMID: 32741650 DOI: 10.1016/j.tree.2020.07.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 12/21/2022]
Abstract
The extent to which the age of parents at reproduction can affect offspring lifespan and other fitness-related traits is important in our understanding of the selective forces shaping life history evolution. In this article, the widely reported negative effects of parental age on offspring lifespan (the 'Lansing effect') is examined. Outlined herein are the potential routes whereby a Lansing effect can occur, whether effects might accumulate across multiple generations, and how the Lansing effect should be viewed as part of a broader framework, considering how parental age affects offspring fitness. The robustness of the evidence for a Lansing effect produced so far, potential confounding variables, and how the underlying mechanisms might best be unravelled through carefully designed experimental studies are discussed.
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Affiliation(s)
- Pat Monaghan
- Institute of Biodiversity, Animal Health and Comparative Medicine, MVLS, Graham Kerr Building, University of Glasgow, Glasgow G12 8QQ, UK.
| | - Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Neil B Metcalfe
- Institute of Biodiversity, Animal Health and Comparative Medicine, MVLS, Graham Kerr Building, University of Glasgow, Glasgow G12 8QQ, UK
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17
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Zajitschek F, Georgolopoulos G, Vourlou A, Ericsson M, Zajitschek SRK, Friberg U, Maklakov AA. Evolution Under Dietary Restriction Decouples Survival From Fecundity in Drosophila melanogaster Females. J Gerontol A Biol Sci Med Sci 2020; 74:1542-1548. [PMID: 29718269 DOI: 10.1093/gerona/gly070] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 04/10/2018] [Indexed: 01/17/2023] Open
Abstract
One of the key tenets of life-history theory is that reproduction and survival are linked and that they trade-off with each other. When dietary resources are limited, reduced reproduction with a concomitant increase in survival is commonly observed. It is often hypothesized that this dietary restriction effect results from strategically reduced investment in reproduction in favor of somatic maintenance to survive starvation periods until resources become plentiful again. We used experimental evolution to test this "waiting-for-the-good-times" hypothesis, which predicts that selection under sustained dietary restriction will favor increased investment in reproduction at the cost of survival because "good-times" never come. We assayed fecundity and survival of female Drosophila melanogaster fruit flies that had evolved for 50 generations on three different diets varying in protein content-low (classic dietary restriction diet), standard, and high-in a full-factorial design. High-diet females evolved overall increased fecundity but showed reduced survival on low and standard diets. Low-diet females evolved reduced survival on low diet without corresponding increase in reproduction. In general, there was little correspondence between the evolution of survival and fecundity across all dietary regimes. Our results contradict the hypothesis that resource reallocation between fecundity and somatic maintenance underpins life span extension under dietary restriction.
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Affiliation(s)
- Felix Zajitschek
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia.,Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Sweden
| | | | - Anna Vourlou
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Sweden
| | - Maja Ericsson
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Sweden
| | - Susanne R K Zajitschek
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia.,Doñana Biological Station, EBD-CSIC, Seville, Spain.,Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Sweden
| | - Urban Friberg
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Sweden.,IFM Biology, AVIAN Behavioural, Genomics and Physiology Group, Linköping University, Sweden
| | - Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Sweden.,School of Biological Sciences, Norwich Research Park, University of East Anglia, UK
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18
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Lind MI, Zwoinska MK, Andersson J, Carlsson H, Krieg T, Larva T, Maklakov AA. Environmental variation mediates the evolution of anticipatory parental effects. Evol Lett 2020; 4:371-381. [PMID: 32774885 PMCID: PMC7403678 DOI: 10.1002/evl3.177] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 05/11/2020] [Indexed: 12/02/2022] Open
Abstract
Theory maintains that when future environment is predictable, parents should adjust the phenotype of their offspring to match the anticipated environment. The plausibility of positive anticipatory parental effects is hotly debated and the experimental evidence for the evolution of such effects is currently lacking. We experimentally investigated the evolution of anticipatory maternal effects in a range of environments that differ drastically in how predictable they are. Populations of the nematode Caenorhabditis remanei, adapted to 20°C, were exposed to a novel temperature (25°C) for 30 generations with either positive or zero correlation between parent and offspring environment. We found that populations evolving in novel environments that were predictable across generations evolved a positive anticipatory maternal effect, because they required maternal exposure to 25°C to achieve maximum reproduction in that temperature. In contrast, populations evolving under zero environmental correlation had lost this anticipatory maternal effect. Similar but weaker patterns were found if instead rate‐sensitive population growth was used as a fitness measure. These findings demonstrate that anticipatory parental effects evolve in response to environmental change so that ill‐fitting parental effects can be rapidly lost. Evolution of positive anticipatory parental effects can aid population viability in rapidly changing but predictable environments.
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Affiliation(s)
- Martin I Lind
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden.,Centre for Biodiversity Dynamics, Department of Biology Norwegian University of Science and Technology (NTNU) Trondheim NO-7491 Norway
| | - Martyna K Zwoinska
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden
| | - Johan Andersson
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden
| | - Hanne Carlsson
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden.,School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Therese Krieg
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden
| | - Tuuli Larva
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden
| | - Alexei A Maklakov
- Animal Ecology, Department of Ecology and Genetics Uppsala University Uppsala 752 36 Sweden.,School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
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19
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Spagopoulou F, Teplitsky C, Lind MI, Chantepie S, Gustafsson L, Maklakov AA. Silver-spoon upbringing improves early-life fitness but promotes reproductive ageing in a wild bird. Ecol Lett 2020; 23:994-1002. [PMID: 32239642 DOI: 10.1111/ele.13501] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/20/2020] [Accepted: 03/03/2020] [Indexed: 01/07/2023]
Abstract
Early-life conditions can have long-lasting effects and organisms that experience a poor start in life are often expected to age at a faster rate. Alternatively, individuals raised in high-quality environments can overinvest in early-reproduction resulting in rapid ageing. Here we use a long-term experimental manipulation of early-life conditions in a natural population of collared flycatchers (Ficedula albicollis), to show that females raised in a low-competition environment (artificially reduced broods) have higher early-life reproduction but lower late-life reproduction than females raised in high-competition environment (artificially increased broods). Reproductive success of high-competition females peaked in late-life, when low-competition females were already in steep reproductive decline and suffered from a higher mortality rate. Our results demonstrate that 'silver-spoon' natal conditions increase female early-life performance at the cost of faster reproductive ageing and increased late-life mortality. These findings demonstrate experimentally that natal environment shapes individual variation in reproductive and actuarial ageing in nature.
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Affiliation(s)
- Foteini Spagopoulou
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvagen 18D, 75236, Uppsala, Sweden
| | - Céline Teplitsky
- CEFE, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvagen 18D, 75236, Uppsala, Sweden
| | - Stéphane Chantepie
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Lars Gustafsson
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvagen 18D, 75236, Uppsala, Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Norbyvagen 18D, 75236, Uppsala, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
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20
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Zwoinska MK, Larva T, Sekajova Z, Carlsson H, Meurling S, Maklakov AA. Artificial selection for increased dispersal results in lower fitness. J Evol Biol 2019; 33:217-224. [PMID: 31677316 DOI: 10.1111/jeb.13563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/25/2019] [Accepted: 10/29/2019] [Indexed: 11/30/2022]
Abstract
Dispersal often covaries with other traits, and this covariation was shown to have a genetic basis. Here, we wanted to explore to what extent genetic constraints and correlational selection can explain patterns of covariation between dispersal and key life-history traits-lifespan and reproduction. A prediction from the fitness-associated dispersal hypothesis was that lower genetic quality is associated with higher dispersal propensity as driven by the benefits of genetic mixing. We wanted to contrast it with a prediction from a different model that individuals putting more emphasis on current rather than future reproduction disperse more, as they are expected to be more risk-prone and exploratory. However, if dispersal has inherent costs, this will also result in a negative genetic correlation between higher rates of dispersal and some aspects of performance. To explore this issue, we used the dioecious nematode Caenorhabditis remanei and selected for increased and decreased dispersal propensity for 10 generations, followed by five generations of relaxed selection. Dispersal propensity responded to selection, and females from high-dispersal lines dispersed more than females from low-dispersal lines. Females selected for increased dispersal propensity produced fewer offspring and were more likely to die from matricide, which is associated with a low physiological condition in Caenorhabditis nematodes. There was no evidence for differences in age-specific reproductive effort between high- and low-dispersal females. Rather, reproductive output of high-dispersal females was consistently reduced. We argue that our data provide support for the fitness-associated dispersal hypothesis.
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Affiliation(s)
- Martyna K Zwoinska
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden.,Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Tuuli Larva
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Zuzana Sekajova
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Hanne Carlsson
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden.,School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Sara Meurling
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Alexei A Maklakov
- Department of Animal Ecology, Uppsala University, Uppsala, Sweden.,School of Biological Sciences, University of East Anglia, Norwich, UK
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21
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Wylde Z, Spagopoulou F, Hooper AK, Maklakov AA, Bonduriansky R. Parental breeding age effects on descendants' longevity interact over 2 generations in matrilines and patrilines. PLoS Biol 2019; 17:e3000556. [PMID: 31765371 PMCID: PMC6901263 DOI: 10.1371/journal.pbio.3000556] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 12/09/2019] [Accepted: 11/07/2019] [Indexed: 01/09/2023] Open
Abstract
Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does and that breeding age effects can interact over 2 generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over 2 generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grand-parental ages at breeding on descendants' mortality rate and life span in both matrilines and patrilines. These breeding age effects were not modulated by grand-parental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intrapopulation variation in mortality and longevity.
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Affiliation(s)
- Zachariah Wylde
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Foteini Spagopoulou
- Uppsala Centre for Evolution and Genomics, Uppsala University, Uppsala, Sweden
| | - Amy K. Hooper
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Alexei A. Maklakov
- Uppsala Centre for Evolution and Genomics, Uppsala University, Uppsala, Sweden
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Russell Bonduriansky
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
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22
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Abstract
Despite tremendous progress in recent years, our understanding of the evolution of ageing is still incomplete. A dominant paradigm maintains that ageing evolves due to the competing energy demands of reproduction and somatic maintenance leading to slow accumulation of unrepaired cellular damage with age. However, the centrality of energy trade-offs in ageing has been increasingly challenged as studies in different organisms have uncoupled the trade-off between reproduction and longevity. An emerging theory is that ageing instead is caused by biological processes that are optimized for early-life function but become harmful when they continue to run-on unabated in late life. This idea builds on the realization that early-life regulation of gene expression can break down in late life because natural selection is too weak to optimize it. Empirical evidence increasingly supports the hypothesis that suboptimal gene expression in adulthood can result in physiological malfunction leading to organismal senescence. We argue that the current state of the art in the study of ageing contradicts the widely held view that energy trade-offs between growth, reproduction, and longevity are the universal underpinning of senescence. Future research should focus on understanding the relative contribution of energy and function trade-offs to the evolution and expression of ageing.
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Affiliation(s)
- Alexei A Maklakov
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
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23
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Berg EC, Lind MI, Monahan S, Bricout S, Maklakov AA. Kin but less than kind: within-group male relatedness does not increase female fitness in seed beetles. Proc Biol Sci 2019; 286:20191664. [PMID: 31506055 PMCID: PMC6742989 DOI: 10.1098/rspb.2019.1664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Theory maintains within-group male relatedness can mediate sexual conflict by reducing male-male competition and collateral harm to females. We tested whether male relatedness can lessen female harm in the seed beetle Callosobruchus maculatus. Male relatedness did not influence female lifetime reproductive success or individual fitness across two different ecologically relevant scenarios of mating competition. However, male relatedness marginally improved female survival. Because male relatedness improved female survival in late life when C. maculatus females are no longer producing offspring, our results do not provide support for the role of within-group male relatedness in mediating sexual conflict. The fact that male relatedness improves the post-reproductive part of the female life cycle strongly suggests that the effect is non-adaptive. We discuss adaptive and non-adaptive mechanisms that could result in reduced female harm in this and previous studies, and suggest that cognitive error is a likely explanation.
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Affiliation(s)
- Elena C Berg
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - Martin I Lind
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Shannon Monahan
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - Sophie Bricout
- Department of Computer Science, Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Uppsala, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
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24
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Lind MI, Ravindran S, Sekajova Z, Carlsson H, Hinas A, Maklakov AA. Experimentally reduced insulin/IGF-1 signaling in adulthood extends lifespan of parents and improves Darwinian fitness of their offspring. Evol Lett 2019; 3:207-216. [PMID: 31007945 PMCID: PMC6457396 DOI: 10.1002/evl3.108] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/06/2019] [Indexed: 11/29/2022] Open
Abstract
Classical theory maintains that ageing evolves via energy trade-offs between reproduction and survival leading to accumulation of unrepaired cellular damage with age. In contrast, the emerging new theory postulates that ageing evolves because of deleterious late-life hyper-function of reproduction-promoting genes leading to excessive biosynthesis in late-life. The hyper-function theory uniquely predicts that optimizing nutrient-sensing molecular signaling in adulthood can simultaneously postpone ageing and increase Darwinian fitness. Here, we show that reducing evolutionarily conserved insulin/IGF-1 nutrient-sensing signaling via daf-2 RNA interference (RNAi) fulfils this prediction in Caenorhabditis elegans nematodes. Long-lived daf-2 RNAi parents showed normal fecundity as self-fertilizing hermaphrodites and improved late-life reproduction when mated to males. Remarkably, the offspring of daf-2 RNAi parents had higher Darwinian fitness across three different genotypes. Thus, reduced nutrient-sensing signaling in adulthood improves both parental longevity and offspring fitness supporting the emerging view that suboptimal gene expression in late-life lies at the heart of ageing.
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Affiliation(s)
- Martin I. Lind
- Animal Ecology, Department of Ecology and GeneticsUppsala UniversityUppsala752 36Sweden
| | - Sanjana Ravindran
- Animal Ecology, Department of Ecology and GeneticsUppsala UniversityUppsala752 36Sweden
| | - Zuzana Sekajova
- Animal Ecology, Department of Ecology and GeneticsUppsala UniversityUppsala752 36Sweden
| | - Hanne Carlsson
- Animal Ecology, Department of Ecology and GeneticsUppsala UniversityUppsala752 36Sweden
- School of Biological SciencesUniversity of East AngliaNorwichNR4 7TJUnited Kingdom
| | - Andrea Hinas
- Department of Cell and Molecular BiologyUppsala UniversityUppsala751 24Sweden
| | - Alexei A. Maklakov
- Animal Ecology, Department of Ecology and GeneticsUppsala UniversityUppsala752 36Sweden
- School of Biological SciencesUniversity of East AngliaNorwichNR4 7TJUnited Kingdom
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25
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Alavioon G, Cabrera Garcia A, LeChatelier M, Maklakov AA, Immler S. Selection for longer lived sperm within ejaculate reduces reproductive ageing in offspring. Evol Lett 2019; 3:198-206. [PMID: 31289692 PMCID: PMC6591544 DOI: 10.1002/evl3.101] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/22/2019] [Indexed: 12/11/2022] Open
Abstract
Males produce numerous sperm in a single ejaculate that greatly outnumber their potential egg targets. Recent studies found that phenotypic and genotypic variation among sperm in a single ejaculate of a male affects the fitness and performance of the resulting offspring. Specifically, within-ejaculate sperm selection for sperm longevity increased the performance of the resulting offspring in several key life-history traits in early life. Because increased early-life reproductive performance often correlates with rapid ageing, it is possible that within-ejaculate sperm selection increases early-life fitness at the cost of accelerated senescence. Alternatively, within-ejaculate sperm selection could improve offspring quality throughout the life cycle, including reduced age-specific deterioration. We tested the two alternative hypotheses in an experimental setup using zebrafish Danio rerio. We found that within-ejaculate sperm selection for sperm longevity reduced age-specific deterioration of fecundity and offspring survival but had no effect on fertilization success in males. Remarkably, we found an opposing effect of within-ejaculate sperm selection on female fecundity, where selection for sperm longevity resulted in increased early-life performance followed by a slow decline, while females sired by unselected sperm started low but increased their fecundity with age. Intriguingly, within-ejaculate sperm selection also reduced the age-specific decline in fertilization success in females, suggesting that selection for sperm longevity improves at least some aspects of female reproductive ageing. These results demonstrate that within-ejaculate variation in sperm phenotype contributes to individual variation in animal life histories in the two sexes and may have important implications for assisted fertilization programs in livestock and humans.
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Affiliation(s)
- Ghazal Alavioon
- Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Norbyvägen 18D 75 236 Uppsala Sweden
| | - Andrea Cabrera Garcia
- Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Norbyvägen 18D 75 236 Uppsala Sweden
| | - Magali LeChatelier
- Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Norbyvägen 18D 75 236 Uppsala Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Norbyvägen 18D 75 236 Uppsala Sweden.,School of Biological Sciences University of East Anglia Norwich Research Park Norwich NR4 7TJ United Kingdom
| | - Simone Immler
- Department of Ecology and Genetics, Evolutionary Biology Centre Uppsala University Norbyvägen 18D 75 236 Uppsala Sweden.,School of Biological Sciences University of East Anglia Norwich Research Park Norwich NR4 7TJ United Kingdom
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26
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Erkosar B, Yashiro E, Zajitschek F, Friberg U, Maklakov AA, van der Meer JR, Kawecki TJ. Host diet mediates a negative relationship between abundance and diversity of Drosophila gut microbiota. Ecol Evol 2018; 8:9491-9502. [PMID: 30377517 PMCID: PMC6194258 DOI: 10.1002/ece3.4444] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 07/12/2018] [Accepted: 07/18/2018] [Indexed: 02/01/2023] Open
Abstract
Nutrient supply to ecosystems has major effects on ecological diversity, but it is unclear to what degree the shape of this relationship is general versus dependent on the specific environment or community. Although the diet composition in terms of the source or proportions of different nutrient types is known to affect gut microbiota composition, the relationship between the quantity of nutrients supplied and the abundance and diversity of the intestinal microbial community remains to be elucidated. Here, we address this relationship using replicate populations of Drosophila melanogaster maintained over multiple generations on three diets differing in the concentration of yeast (the only source of most nutrients). While a 6.5-fold increase in yeast concentration led to a 100-fold increase in the total abundance of gut microbes, it caused a major decrease in their alpha diversity (by 45-60% depending on the diversity measure). This was accompanied by only minor shifts in the taxonomic affiliation of the most common operational taxonomic units (OTUs). Thus, nutrient concentration in host diet mediates a strong negative relationship between the nutrient abundance and microbial diversity in the Drosophila gut ecosystem.
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Affiliation(s)
- Berra Erkosar
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
- Department of Fundamental MicrobiologyUniversity of LausanneLausanneSwitzerland
| | - Erika Yashiro
- Department of Fundamental MicrobiologyUniversity of LausanneLausanneSwitzerland
| | - Felix Zajitschek
- Department of Animal EcologyEvolutionary Biology CentreUppsala UniversityUppsalaSweden
- Evolution and Ecology Research CenterSchool of Biological, Earth and Environmental SciencesUniversity of New South WalesSydneyNSWAustralia
| | - Urban Friberg
- IFM BiologyAVIAN Behavioural Genomics and Physiology GroupLinköping UniversityLinköpingSweden
| | - Alexei A. Maklakov
- Department of Animal EcologyEvolutionary Biology CentreUppsala UniversityUppsalaSweden
| | - Jan R. van der Meer
- Department of Fundamental MicrobiologyUniversity of LausanneLausanneSwitzerland
| | - Tadeusz J. Kawecki
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
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27
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Maklakov AA, Carlsson H, Denbaum P, Lind MI, Mautz B, Hinas A, Immler S. Antagonistically pleiotropic allele increases lifespan and late-life reproduction at the cost of early-life reproduction and individual fitness. Proc Biol Sci 2018; 284:rspb.2017.0376. [PMID: 28615498 DOI: 10.1098/rspb.2017.0376] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/15/2017] [Indexed: 01/03/2023] Open
Abstract
Evolutionary theory of ageing maintains that increased allocation to early-life reproduction results in reduced somatic maintenance, which is predicted to compromise longevity and late-life reproduction. This prediction has been challenged by the discovery of long-lived mutants with no loss of fecundity. The first such long-lived mutant was found in the nematode worm Caenorhabditis elegans Specifically, partial loss-of-function mutation in the age-1 gene, involved in the nutrient-sensing insulin/insulin-like growth factor signalling pathway, confers longevity, as well as increased resistance to pathogens and to temperature stress without appreciable fitness detriment. Here, we show that the long-lived age-1(hx546) mutant has reduced fecundity and offspring production in early-life, but increased fecundity, hatching success, and offspring production in late-life compared with wild-type worms under standard conditions. However, reduced early-life performance of long-lived mutant animals was not fully compensated by improved performance in late-life and resulted in reduced individual fitness. These results suggest that the age-1(hx546) allele has opposing effects on early-life versus late-life fitness in accordance with antagonistic pleiotropy (AP) and disposable soma theories of ageing. These findings support the theoretical conjecture that experimental studies based on standing genetic variation underestimate the importance of AP in the evolution of ageing.
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Affiliation(s)
- Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden .,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, Norfolk, UK
| | - Hanne Carlsson
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Philip Denbaum
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Martin I Lind
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Brian Mautz
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden
| | - Andrea Hinas
- Department of Cell and Molecular Biology, Uppsala University, PO Box 596, Uppsala 75124, Sweden
| | - Simone Immler
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Norbyvagen 18D, Uppsala 752 36, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, Norfolk, UK
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28
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Griffin RM, Hayward AD, Bolund E, Maklakov AA, Lummaa V. Sex differences in adult mortality rate mediated by early-life environmental conditions. Ecol Lett 2017; 21:235-242. [PMID: 29210148 DOI: 10.1111/ele.12888] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 09/18/2017] [Accepted: 11/06/2017] [Indexed: 12/16/2022]
Abstract
Variation in sex differences is affected by both genetic and environmental variation, with rapid change in sex differences being more likely due to environmental change. One case of rapid change in sex differences is human lifespan, which has become increasingly female-biased in recent centuries. Long-term consequences of variation in the early-life environment may, in part, explain such variation in sex differences, but whether the early-life environment mediates sex differences in life-history traits is poorly understood in animals. Combining longitudinal data on 60 cohorts of pre-industrial Finns with environmental data, we show that the early-life environment is associated with sex differences in adult mortality and expected lifespan. Specifically, low infant survival rates and high rye yields (an important food source) in early-life are associated with female-bias in adult lifespan. These results support the hypothesis that environmental change has the potential to affect sex differences in life-history traits in natural populations of long-lived mammals.
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Affiliation(s)
- Robert M Griffin
- Department of Biology, University of Turku, 20014, Turku, Finland
| | - Adam D Hayward
- Department of Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA, UK
| | - Elisabeth Bolund
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, 752 36, Sweden
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, 752 36, Sweden.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Virpi Lummaa
- Department of Biology, University of Turku, 20014, Turku, Finland
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29
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Lind MI, Chen HY, Cortazar-Chinarro M, Maklakov AA. Rapamycin additively extends lifespan in short- and long-lived lines of the nematode Caenorhabditis remanei. Exp Gerontol 2017; 90:79-82. [DOI: 10.1016/j.exger.2017.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 12/07/2016] [Accepted: 01/19/2017] [Indexed: 01/09/2023]
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Lind MI, Chen H, Meurling S, Guevara Gil AC, Carlsson H, Zwoinska MK, Andersson J, Larva T, Maklakov AA. Slow development as an evolutionary cost of long life. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12840] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Martin I. Lind
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Hwei‐yen Chen
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Sara Meurling
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | | | - Hanne Carlsson
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Martyna K. Zwoinska
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Johan Andersson
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Tuuli Larva
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
| | - Alexei A. Maklakov
- Animal Ecology Department of Ecology and Genetics Uppsala University 752 36 Uppsala Sweden
- School of Biological Sciences University of East Anglia Norwich Research Park Norwich NR4 7TJ UK
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31
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Hooper AK, Spagopoulou F, Wylde Z, Maklakov AA, Bonduriansky R. Ontogenetic timing as a condition‐dependent life history trait: High‐condition males develop quickly, peak early, and age fast. Evolution 2017; 71:671-685. [DOI: 10.1111/evo.13172] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 12/19/2016] [Indexed: 02/04/2023]
Affiliation(s)
- Amy K. Hooper
- School of Biological, Earth and Environmental Sciences, Evolution and Ecology Research Centre University of New South Wales Sydney NSW 2052 Australia
| | - Foteini Spagopoulou
- Ageing Research Group, Department of Animal Ecology, Evolutionary Biology Centre Uppsala University Uppsala Sweden
| | - Zachariah Wylde
- School of Biological, Earth and Environmental Sciences, Evolution and Ecology Research Centre University of New South Wales Sydney NSW 2052 Australia
| | - Alexei A. Maklakov
- Ageing Research Group, Department of Animal Ecology, Evolutionary Biology Centre Uppsala University Uppsala Sweden
| | - Russell Bonduriansky
- School of Biological, Earth and Environmental Sciences, Evolution and Ecology Research Centre University of New South Wales Sydney NSW 2052 Australia
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32
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Zwoinska MK, Maklakov AA, Kawecki TJ, Hollis B. Experimental evolution of slowed cognitive aging in Drosophila melanogaster. Evolution 2016; 71:662-670. [PMID: 28000915 DOI: 10.1111/evo.13156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 12/09/2016] [Indexed: 11/30/2022]
Abstract
Reproductive output and cognitive performance decline in parallel during aging, but it is unknown whether this reflects a shared genetic architecture or merely the declining force of natural selection acting independently on both traits. We used experimental evolution in Drosophila melanogaster to test for the presence of genetic variation for slowed cognitive aging, and assess its independence from that responsible for other traits' decline with age. Replicate experimental populations experienced either joint selection on learning and reproduction at old age (Old + Learning), selection on late-life reproduction alone (Old), or a standard two-week culture regime (Young). Within 20 generations, the Old + Learning populations evolved a slower decline in learning with age than both the Old and Young populations, revealing genetic variation for cognitive aging. We found little evidence for a genetic correlation between cognitive and demographic aging: although the Old + Learning populations tended to show higher late-life fecundity than Old populations, they did not live longer. Likewise, selection for late reproduction alone did not result in improved late-life learning. Our results demonstrate that Drosophila harbor genetic variation for cognitive aging that is largely independent from genetic variation for demographic aging and suggest that these two aspects of aging may not necessarily follow the same trajectories.
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Affiliation(s)
- Martyna K Zwoinska
- Department of Animal Ecology, Uppsala University, 752 36, Uppsala, Sweden.,Department of Ecology and Evolution, University of Lausanne, CH 1015, Lausanne, Switzerland
| | - Alexei A Maklakov
- Department of Animal Ecology, Uppsala University, 752 36, Uppsala, Sweden
| | - Tadeusz J Kawecki
- Department of Ecology and Evolution, University of Lausanne, CH 1015, Lausanne, Switzerland
| | - Brian Hollis
- Department of Ecology and Evolution, University of Lausanne, CH 1015, Lausanne, Switzerland.,School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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Zajitschek F, Zajitschek SRK, Canton C, Georgolopoulos G, Friberg U, Maklakov AA. Evolution under dietary restriction increases male reproductive performance without survival cost. Proc Biol Sci 2016; 283:20152726. [PMID: 26911958 DOI: 10.1098/rspb.2015.2726] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Dietary restriction (DR), a reduction in nutrient intake without malnutrition, is the most reproducible way to extend lifespan in a wide range of organisms across the tree of life, yet the evolutionary underpinnings of the DR effect on lifespan are still widely debated. The leading theory suggests that this effect is adaptive and results from reallocation of resources from reproduction to somatic maintenance, in order to survive periods of famine in nature. However, such response would cease to be adaptive when DR is chronic and animals are selected to allocate more resources to reproduction. Nevertheless, chronic DR can also increase the strength of selection resulting in the evolution of more robust genotypes. We evolved Drosophila melanogaster fruit flies on 'DR', 'standard' and 'high' adult diets in replicate populations with overlapping generations. After approximately 25 generations of experimental evolution, male 'DR' flies had higher fitness than males from 'standard' and 'high' populations. Strikingly, this increase in reproductive success did not come at a cost to survival. Our results suggest that sustained DR selects for more robust male genotypes that are overall better in converting resources into energy, which they allocate mostly to reproduction.
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Affiliation(s)
- Felix Zajitschek
- School of Biological Sciences, Monash University, Clayton, Victoria 3800, Australia Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Susanne R K Zajitschek
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden Doñana Biological Station, Spanish Research Council CSIC, c/ Americo Vespucio, s/n, Isla de la Cartuja, 41092 Sevilla, Spain
| | - Cindy Canton
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Grigorios Georgolopoulos
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
| | - Urban Friberg
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden IFM Biology, AVIAN Behavioural, Genomics and Physiology Group, Linköping University, Linköping 58183, Sweden
| | - Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala 75236, Sweden
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Abstract
Male nematodes secrete pheromones that accelerate the somatic senescence of potential mates. A new study shows that this harm most likely is an unintended by-product of the males' aim to speed up sexual maturation and delay reproductive senescence of future partners.
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Affiliation(s)
- Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Norbyvagen 18D, SE-752 36 Uppsala University, Sweden.
| | - Urban Friberg
- IFM Biology, AVIAN Behavioural, Genomics and Physiology Group, Linkoping University, Linkoping 58183, Sweden
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35
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Berger D, Martinossi-Allibert I, Grieshop K, Lind MI, Maklakov AA, Arnqvist G. Intralocus Sexual Conflict and the Tragedy of the Commons in Seed Beetles. Am Nat 2016; 188:E98-E112. [DOI: 10.1086/687963] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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36
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Berger D, You T, Minano MR, Grieshop K, Lind MI, Arnqvist G, Maklakov AA. Sexually antagonistic selection on genetic variation underlying both male and female same-sex sexual behavior. BMC Evol Biol 2016; 16:88. [PMID: 27175796 PMCID: PMC4866275 DOI: 10.1186/s12862-016-0658-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 04/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Intralocus sexual conflict, arising from selection for different alleles at the same locus in males and females, imposes a constraint on sex-specific adaptation. Intralocus sexual conflict can be alleviated by the evolution of sex-limited genetic architectures and phenotypic expression, but pleiotropic constraints may hinder this process. Here, we explored putative intralocus sexual conflict and genetic (co)variance in a poorly understood behavior with near male-limited expression. Same-sex sexual behaviors (SSBs) generally do not conform to classic evolutionary models of adaptation but are common in male animals and have been hypothesized to result from perception errors and selection for high male mating rates. However, perspectives incorporating sex-specific selection on genes shared by males and females to explain the expression and evolution of SSBs have largely been neglected. RESULTS We performed two parallel sex-limited artificial selection experiments on SSB in male and female seed beetles, followed by sex-specific assays of locomotor activity and male sex recognition (two traits hypothesized to be functionally related to SSB) and adult reproductive success (allowing us to assess fitness consequences of genetic variance in SSB and its correlated components). Our experiments reveal both shared and sex-limited genetic variance for SSB. Strikingly, genetically correlated responses in locomotor activity and male sex-recognition were associated with sexually antagonistic fitness effects, but these effects differed qualitatively between male and female selection lines, implicating intralocus sexual conflict at both male- and female-specific genetic components underlying SSB. CONCLUSIONS Our study provides experimental support for the hypothesis that widespread pleiotropy generates pervasive intralocus sexual conflict governing the expression of SSBs, suggesting that SSB in one sex can occur due to the expression of genes that carry benefits in the other sex.
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Affiliation(s)
- David Berger
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden.
| | - Tao You
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
| | - Maravillas R Minano
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
| | - Karl Grieshop
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
| | - Martin I Lind
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
| | - Göran Arnqvist
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
| | - Alexei A Maklakov
- Animal Ecology, Department of Ecology and Genetics, Uppsala University, Evolutionary Biology Centre, Norbyvägen 18D, 75105, Uppsala, Sweden
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37
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Bolund E, Lummaa V, Smith KR, Hanson HA, Maklakov AA. Reduced costs of reproduction in females mediate a shift from a male-biased to a female-biased lifespan in humans. Sci Rep 2016; 6:24672. [PMID: 27087670 PMCID: PMC4834564 DOI: 10.1038/srep24672] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 04/04/2016] [Indexed: 11/21/2022] Open
Abstract
The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution.
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Affiliation(s)
- Elisabeth Bolund
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala SE-752 36, Sweden
| | - Virpi Lummaa
- Department of Biology, University of Turku, FIN-20014 Turku, Finland.,Department of Animal &Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Ken R Smith
- Department of Family and Consumer Studies and Population Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Heidi A Hanson
- Department of Family and Preventive Medicine and Population Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Alexei A Maklakov
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala SE-752 36, Sweden
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Zwoinska MK, Lind MI, Cortazar-Chinarro M, Ramsden M, Maklakov AA. Selection on learning performance results in the correlated evolution of sexual dimorphism in life history. Evolution 2016; 70:342-57. [DOI: 10.1111/evo.12862] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 01/04/2016] [Accepted: 01/07/2016] [Indexed: 12/15/2022]
Affiliation(s)
- Martyna K. Zwoinska
- Department of Animal Ecology, Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Martin I. Lind
- Department of Animal Ecology, Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Maria Cortazar-Chinarro
- Department of Animal Ecology, Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Mark Ramsden
- Department of Animal Ecology, Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Alexei A. Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
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Lind MI, Zwoinska MK, Meurling S, Carlsson H, Maklakov AA. Sex-specific Tradeoffs With Growth and Fitness Following Life-span Extension by Rapamycin in an Outcrossing Nematode,Caenorhabditis remanei. J Gerontol A Biol Sci Med Sci 2015; 71:882-90. [DOI: 10.1093/gerona/glv174] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 09/14/2015] [Indexed: 01/05/2023] Open
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40
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Affiliation(s)
- Alexei A. Maklakov
- Department of Animal Ecology; Evolutionary Biology Centre; Ageing Research Group; Uppsala University; Uppsala Sweden
| | - Locke Rowe
- Department of Ecology and Evolutionary Biology; University of Toronto; Toronto ON Canada
| | - Urban Friberg
- Department of Evolutionary Biology; Evolutionary Biology Centre; Ageing Research Group; Uppsala University; Uppsala Sweden
- IFM Biology; AVIAN Behavioural Genomics and Physiology Group; Linköping University; Linköping Sweden
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41
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Kotrschal A, Corral-Lopez A, Zajitschek S, Immler S, Maklakov AA, Kolm N. Positive genetic correlation between brain size and sexual traits in male guppies artificially selected for brain size. J Evol Biol 2015; 28:841-50. [PMID: 25705852 PMCID: PMC4949642 DOI: 10.1111/jeb.12608] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 02/17/2015] [Indexed: 11/28/2022]
Abstract
Brain size is an energetically costly trait to develop and maintain. Investments into other costly aspects of an organism's biology may therefore place important constraints on brain size evolution. Sexual traits are often costly and could therefore be traded off against neural investment. However, brain size may itself be under sexual selection through mate choice on cognitive ability. Here, we use guppy (Poecilia reticulata) lines selected for large and small brain size relative to body size to investigate the relationship between brain size, a large suite of male primary and secondary sexual traits, and body condition index. We found no evidence for trade-offs between brain size and sexual traits. Instead, larger-brained males had higher expression of several primary and precopulatory sexual traits--they had longer genitalia, were more colourful and developed longer tails than smaller-brained males. Larger-brained males were also in better body condition when housed in single-sex groups. There was no difference in post-copulatory sexual traits between males from the large- and small-brained lines. Our data do not support the hypothesis that investment into sexual traits is an important limiting factor to brain size evolution, but instead suggest that brain size and several sexual traits are positively genetically correlated.
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Affiliation(s)
- A Kotrschal
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden; Department of Zoology/Ethology, Stockholm University, Stockholm, Sweden
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42
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Berger D, Berg EC, Widegren W, Arnqvist G, Maklakov AA. Multivariate intralocus sexual conflict in seed beetles. Evolution 2014; 68:3457-69. [DOI: 10.1111/evo.12528] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 09/01/2014] [Indexed: 12/22/2022]
Affiliation(s)
- David Berger
- Animal Ecology; Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Elena C. Berg
- Ageing Research Group; Animal Ecology; Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
- Department of Computer Science; Mathematics, and Environmental Science, The American University of Paris, Paris, France
| | - William Widegren
- Ageing Research Group; Animal Ecology; Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Göran Arnqvist
- Animal Ecology; Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Alexei A. Maklakov
- Ageing Research Group; Animal Ecology; Department of Ecology and Genetics; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
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Chen HY, Maklakov AA. Condition dependence of male mortality drives the evolution of sex differences in longevity. Curr Biol 2014; 24:2423-7. [PMID: 25308078 DOI: 10.1016/j.cub.2014.08.055] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/18/2014] [Accepted: 08/20/2014] [Indexed: 11/18/2022]
Abstract
Males and females age at different rates and have different life expectancies across the animal kingdom, but what causes the longevity "gender gaps" remains one of the most fiercely debated puzzles among biologists and demographers. Classic theory predicts that the sex experiencing higher rate of extrinsic mortality evolves faster aging and reduced longevity. However, condition dependence of mortality can counter this effect by selecting against senescence in whole-organism performance. Contrary to the prevailing view but in line with an emerging new theory, we show that the evolution of sex difference in longevity depends on the factors that cause sex-specific mortality and cannot be predicted from the mortality rate alone. Experimental evolution in an obligately sexual roundworm, Caenorhabditis remanei, in which males live longer than females, reveals that sexual dimorphism in longevity erodes rapidly when the extrinsic mortality in males is increased at random. We thus experimentally demonstrate evolution of the sexual monomorphism in longevity in a sexually dimorphic organism. Strikingly, when extrinsic mortality is increased in a way that favors survival of fast-moving individuals, males evolve increased longevities, thereby widening the gender gap. Thus, sex-specific selection on whole-organism performance in males renders them less prone to the ravages of old age than females, despite higher rates of extrinsic mortality. Our results reconcile previous research with recent theoretical breakthroughs by showing that sexual dimorphism in longevity evolves rapidly and predictably as a result of the sex-specific interactions between environmental hazard and organism's condition.
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Affiliation(s)
- Hwei-yen Chen
- Ageing Research Group, Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, 752 36 Uppsala, Sweden
| | - Alexei A Maklakov
- Ageing Research Group, Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, 752 36 Uppsala, Sweden.
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44
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Abstract
Fruit flies selected to reproduce on the fifth day of adult life for many generations remarkably keep on living for six weeks, showing no change in lifespan. A mutation-accumulation experiment suggests that the same genes confer high early-life fitness and long life.
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Affiliation(s)
- Alexei A Maklakov
- Ageing Research Group, Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
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Lind MI, Berg EC, Alavioon G, Maklakov AA. Evolution of differential maternal age effects on male and female offspring development and longevity. Funct Ecol 2014. [DOI: 10.1111/1365-2435.12308] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin I. Lind
- Ageing Research Group Department of Animal Ecology Evolutionary Biology Centre Uppsala University Uppsala 75236 Sweden
| | - Elena C. Berg
- Ageing Research Group Department of Animal Ecology Evolutionary Biology Centre Uppsala University Uppsala 75236 Sweden
- Department of Computer Science, Math & Science American University of Paris 31 Avenue Bosquet Paris 75007 France
| | - Ghazal Alavioon
- Ageing Research Group Department of Animal Ecology Evolutionary Biology Centre Uppsala University Uppsala 75236 Sweden
| | - Alexei A. Maklakov
- Ageing Research Group Department of Animal Ecology Evolutionary Biology Centre Uppsala University Uppsala 75236 Sweden
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Berger D, Grieshop K, Lind MI, Goenaga J, Maklakov AA, Arnqvist G. INTRALOCUS SEXUAL CONFLICT AND ENVIRONMENTAL STRESS. Evolution 2014; 68:2184-96. [DOI: 10.1111/evo.12439] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 04/10/2014] [Indexed: 11/30/2022]
Affiliation(s)
- David Berger
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
| | - Karl Grieshop
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
| | - Martin I. Lind
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
| | - Julieta Goenaga
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
| | - Alexei A. Maklakov
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
| | - Göran Arnqvist
- Animal Ecology at Department of Ecology and Genetics, Evolutionary Biology Centre; Uppsala University; Norbyvägen 18d SE-75236 Uppsala Sweden
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Abstract
Males and females have different evolutionary interests resulting in sexual conflict over optimal life histories. A new study in Caenorhabditis elegans shows that males hijack female physiology after mating to cause body shrinking and, ultimately, death. But how do males benefit from female demise?
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Affiliation(s)
- Martyna Zwoinska
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, SE-752 36, Sweden
| | - Martin I Lind
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, SE-752 36, Sweden
| | - Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, Uppsala, SE-752 36, Sweden.
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48
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Kotrschal A, Lievens EJP, Dahlbom J, Bundsen A, Semenova S, Sundvik M, Maklakov AA, Winberg S, Panula P, Kolm N. Artificial selection on relative brain size reveals a positive genetic correlation between brain size and proactive personality in the guppy. Evolution 2014; 68:1139-49. [PMID: 24359469 PMCID: PMC4285157 DOI: 10.1111/evo.12341] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 12/09/2013] [Indexed: 01/22/2023]
Abstract
Animal personalities range from individuals that are shy, cautious, and easily stressed (a “reactive” personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a “proactive” personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large- and small-brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large-brained animals were faster to habituate to, and more exploratory in, open field tests. Large-brained females were also bolder. Second, large-brained animals excreted less cortisol in a stressful situation (confinement). Third, large-brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large-brained lines. Overall, the results point toward a more proactive personality type in large-brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness-related aspects of ecology such as dispersal and niche exploration.
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Affiliation(s)
- Alexander Kotrschal
- Department for Integrative Biology and Evolution (KLIVV), Veterinary University Vienna, Savoyenstrasse 1A, 1160 Vienna, Austria; Department of Ecology & Genetics/Animal Ecology, Uppsala University, Norbyvägen 18D, SE-75236 Uppsala, Sweden.
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49
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Rogell B, Widegren W, Hallsson LR, Berger D, Björklund M, Maklakov AA. Sex-dependent evolution of life-history traits following adaptation to climate warming. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12179] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Björn Rogell
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
- Shool of Biological Sciences; Monash University; Clayton 3800 Australia
| | - William Widegren
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
| | - Lára R. Hallsson
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
- Evolution & Ecology Research Centre; School of Biological, Earth and Environmental Sciences, University of New South Wales; Sydney New South Wales 2052 Australia
| | - David Berger
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
| | - Mats Björklund
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
| | - Alexei A. Maklakov
- Department of Animal Ecology; Evolutionary Biology Center, Uppsala University; Uppsala SE-752 36 Sweden
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50
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Maklakov AA, Immler S, Gonzalez-Voyer A, Rönn J, Kolm N. Brains and the city in passerine birds: re-analysis and confirmation of the original result. Biol Lett 2013; 9:20130859. [PMID: 24227048 DOI: 10.1098/rsbl.2013.0859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Alexei A Maklakov
- Department of Animal Ecology, Evolutionary Biology Centre, Uppsala University, , Uppsala, Sweden
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