Fitness costs of parasites explain multiple life history tradeoffs in a wild mammal

SummaryReproduction in wild animals can divert limited resources away from immune defence, resulting in increased parasite burdens. A longstanding prediction of life history theory states that these parasites can harm the reproductive individual, reducing its subsequent fitness and producing reproduction-fitness tradeoffs. Here, we examined associations among reproductive allocation, immunity, parasitism, and subsequent fitness in a wild population of individually identified red deer (Cervus elaphus). Using path analysis, we investigated whether costs of lactation for downstream survival and fecundity were mediated by changes in strongyle nematode count and mucosal antibody levels. Lactating females exhibited increased parasite counts, which were in turn associated with substantially decreased fitness in the following year in terms of overwinter survival, fecundity, subsequent calf weight, and parturition date. This study offers observational evidence for parasite regulation of multiple life history tradeoffs, supporting the role of parasites as an important mediating factor in wild mammal populations.

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Life history tradeoffs in humans increased life expectancy with sperm count reduction

Frontiers in Bioscience ◽

10.2741/4745 ◽

2019 ◽

Vol 24 (4) ◽

pp. 712-722

Author(s):

Rui-An Wang

Keyword(s):

Life History ◽

Life Expectancy ◽

Sperm Count ◽

Life History Tradeoffs

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Fitness of Herbicide-Resistant Weeds: Current Knowledge and Implications for Management

Plants ◽

10.3390/plants8110469 ◽

2019 ◽

Vol 8 (11) ◽

pp. 469 ◽

Cited By ~ 5

Author(s):

Vila-Aiub

Keyword(s):

Life History ◽

Herbicide Resistance ◽

Management Practices ◽

Current Knowledge ◽

Resistance Management ◽

Fitness Cost ◽

Plant Fitness ◽

Resistance Mutations ◽

Fitness Costs ◽

Wide Range

Herbicide resistance is the ultimate evidence of the extraordinary capacity of weeds to evolve under stressful conditions. Despite the extraordinary plant fitness advantage endowed by herbicide resistance mutations in agroecosystems under herbicide selection, resistance mutations are predicted to exhibit an adaptation cost (i.e., fitness cost), relative to the susceptible wild-type, in herbicide untreated conditions. Fitness costs associated with herbicide resistance mutations are not universal and their expression depends on the particular mutation, genetic background, dominance of the fitness cost, and environmental conditions. The detrimental effects of herbicide resistance mutations on plant fitness may arise as a direct impact on fitness-related traits and/or coevolution with changes in other life history traits that ultimately may lead to fitness costs under particular ecological conditions. This brings the idea that a “lower adaptive value” of herbicide resistance mutations represents an opportunity for the design of resistance management practices that could minimize the evolution of herbicide resistance. It is evident that the challenge for weed management practices aiming to control, minimize, or even reverse the frequency of resistance mutations in the agricultural landscape is to “create” those agroecological conditions that could expose, exploit, and exacerbate those life history and/or fitness traits affecting the evolution of herbicide resistance mutations. Ideally, resistance management should implement a wide range of cultural practices leading to environmentally mediated fitness costs associated with herbicide resistance mutations.

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Life-history tradeoffs revealed by seasonal declines in reproductive traits of Arctic-breeding shorebirds

Journal of Avian Biology ◽

10.1111/jav.01531 ◽

2018 ◽

Vol 49 (2) ◽

pp. jav-01531 ◽

Cited By ~ 12

Author(s):

Emily L. Weiser ◽

Stephen C. Brown ◽

Richard B. Lanctot ◽

H. River Gates ◽

Kenneth F. Abraham ◽

...

Keyword(s):

Life History ◽

Reproductive Traits ◽

Life History Tradeoffs

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Life History Tradeoffs in Avian Clutch Size:

An Introduction to Methods and Models in Ecology, Evolution, and Conservation Biology ◽

10.2307/j.ctvcm4gbm.11 ◽

2010 ◽

pp. 36-50

Author(s):

Jon Hess

Keyword(s):

Life History ◽

Clutch Size ◽

Life History Tradeoffs

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Life history tradeoffs and the evolutionary biology of aging

Evolution and Medicine ◽

10.1093/acprof:oso/9780199661718.003.0005 ◽

2013 ◽

pp. 51-64 ◽

Cited By ~ 1

Author(s):

Robert L. Perlman

Keyword(s):

Life History ◽

Evolutionary Biology ◽

Life History Tradeoffs ◽

Biology Of Aging

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Understanding the Evolutionary Ecology of host–pathogen Interactions Provides Insights into the Outcomes of Insect Pest Biocontrol

Viruses ◽

10.3390/v12020141 ◽

2020 ◽

Vol 12 (2) ◽

pp. 141

Author(s):

David J. Páez ◽

Arietta E. Fleming-Davies

Keyword(s):

Population Dynamics ◽

Life History ◽

Transmission Rate ◽

Insect Pest ◽

Pathogen Transmission ◽

Single Strain ◽

Classical Biocontrol ◽

Life History Tradeoffs ◽

Pathogen Strains

The use of viral pathogens to control the population size of pest insects has produced both successful and unsuccessful outcomes. Here, we investigate whether those biocontrol successes and failures can be explained by key ecological and evolutionary processes between hosts and pathogens. Specifically, we examine how heterogeneity in pathogen transmission, ecological and evolutionary tradeoffs, and pathogen diversity affect insect population density and thus successful control. We first review the existing literature and then use numerical simulations of mathematical models to further explore these processes. Our results show that the control of insect densities using viruses depends strongly on the heterogeneity of virus transmission among insects. Overall, increased heterogeneity of transmission reduces the effect of viruses on insect densities and increases the long-term stability of insect populations. Lower equilibrium insect densities occur when transmission is heritable and when there is a tradeoff between mean transmission and insect fecundity compared to when the heterogeneity of transmission arises from non-genetic sources. Thus, the heterogeneity of transmission is a key parameter that regulates the long-term population dynamics of insects and their pathogens. We also show that both heterogeneity of transmission and life-history tradeoffs modulate characteristics of population dynamics such as the frequency and intensity of “boom–bust" population cycles. Furthermore, we show that because of life-history tradeoffs affecting the transmission rate, the use of multiple pathogen strains is more effective than the use of a single strain to control insect densities only when the pathogen strains differ considerably in their transmission characteristics. By quantifying the effects of ecology and evolution on population densities, we are able to offer recommendations to assess the long-term effects of classical biocontrol.

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