Saturating effects of species diversity on life-history evolution in bacteria

Species interactions can play a major role in shaping evolution in new environments. In theory, species interactions can either stimulate evolution by promoting coevolution or inhibit evolution by constraining ecological opportunity. The relative strength of these effects should vary as species richness increases, and yet there has been little evidence for evolution of component species in communities. We evolved bacterial microcosms containing between 1 and 12 species in three different environments. Growth rates and yields of isolates that evolved in communities were lower than those that evolved in monocultures, consistent with recent theory that competition constrains species to specialize on narrower sets of resources. This effect saturated or reversed at higher levels of richness, consistent with theory that directional effects of species interactions should weaken in more diverse communities. Species varied considerably, however, in their responses to both environment and richness levels. Mechanistic models and experiments are now needed to understand and predict joint evolutionary dynamics of species in diverse communities.

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Daphnia as a Model for Eco-evolutionary Dynamics

10.1093/oso/9780190620271.003.0016 ◽

2018 ◽

pp. 403-424

Author(s):

Matthew R. Walsh ◽

Michelle Packer ◽

Shannon Beston ◽

Collin Funkhouser ◽

Michael Gillis ◽

...

Keyword(s):

Life History ◽

Evolutionary Dynamics ◽

Model Organism ◽

Life History Evolution ◽

Ecological Processes ◽

Evolutionary Forces ◽

Evolutionary Changes ◽

History Evolution ◽

Ecological Importance ◽

The Many

Much research has shown that variation in ecological processes can drive rapid evolutionary changes over periods of years to decades. Such contemporary adaptation sets the stage for evolution to have reciprocal impacts on the properties of populations, communities, and ecosystems, with ongoing interactions between ecological and evolutionary forces. The importance and generality of these eco-evolutionary dynamics are largely unknown. In this chapter, we promote the use of water fleas (Daphnia sp.) as a model organism in the exploration of eco-evolutionary interactions in nature. The many characteristics of Daphnia that make them suitable for laboratory study in conjunction with their well-known ecological importance in lakes, position Daphnia to contribute new and important insights into eco-evolutionary dynamics. We first review the influence of key environmental stressors in Daphnia evolution. We then highlight recent work documenting the pathway from life history evolution to ecology using Daphnia as a model. This review demonstrates that much is known about the influence of ecology on Daphnia life history evolution, while research exploring the genomic basis of adaptation as well as the influence of Daphnia life history traits on ecological processes is beginning to accumulate.

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Life history and dispersal timing evolve in response to metapopulation connectedness

10.1101/476093 ◽

2018 ◽

Author(s):

Stefano Masier ◽

Dries Bonte

Keyword(s):

Life History ◽

Evolutionary Dynamics ◽

Local Level ◽

Life History Evolution ◽

Structured Populations ◽

Demographic Traits ◽

Local Selection ◽

And Performance ◽

Interpatch Distance ◽

Dispersal Evolution

AbstractDispersal evolution impacts the fluxes of individuals and hence, connectivity in metapopulations. Connectivity is therefore decoupled from the structural connectedness of the patches within the spatial network. Because of demographic feedbacks, local selection can additionally steer the evolution of other life history traits. We investigated how different levels of connectedness affect dispersal and life history evolution by varying the interpatch distance in replicated experimental metapopulations of the two-spotted spider. We implemented a shuffling treatment to separate local- and metapopulation-level selection.With lower metapopulation connectedness, an increased starvation resistance and delayed dispersal evolved. Intrinsic growth rates evolved at the local level by transgenerational plasticity or epigenetic processes. Changes in patch connectedness thus induce the genetic and non-genetic evolution of dispersal costs and demographic traits at both the local and metapopulation level. These trait changes are anticipated to impact metapopulations eco-evolutionary dynamics, and hence, the persistence and performance of spatially structured populations.

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Pathogen evolution: slow and steady spreads the best

10.1101/225599 ◽

2017 ◽

Author(s):

Todd L. Parsons ◽

Amaury Lambert ◽

Troy Day ◽

Sylvain Gandon

Keyword(s):

Life History ◽

Population Size ◽

Evolutionary Dynamics ◽

Finite Population ◽

Adaptive Dynamics ◽

Life History Evolution ◽

Demographic Stochasticity ◽

Deterministic Models ◽

Evolutionary Forces ◽

History Evolution

AbstractThe theory of life history evolution provides a powerful framework to understand the evolutionary dynamics of pathogens in both epidemic and endemic situations. This framework, however, relies on the assumption that pathogen populations are very large and that one can neglect the effects of demographic stochasticity. Here we expand the theory of life history evolution to account for the effects of finite population size on the evolution of pathogen virulence. We show that demographic stochasticity introduces additional evolutionary forces that can qualitatively affect the dynamics and the evolutionary outcome. We discuss the importance of the shape of pathogen fitness landscape and host heterogeneity on the balance between mutation, selection and genetic drift. In particular, we discuss scenarios where finite population size can dramatically affect classical predictions of deterministic models. This analysis reconciles Adaptive Dynamics with population genetics in finite populations and thus provides a new theoretical toolbox to study life-history evolution in realistic ecological scenarios.

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Pathogen evolution in finite populations: slow and steady spreads the best

Journal of The Royal Society Interface ◽

10.1098/rsif.2018.0135 ◽

2018 ◽

Vol 15 (147) ◽

pp. 20180135 ◽

Cited By ~ 5

Author(s):

Todd L. Parsons ◽

Amaury Lambert ◽

Troy Day ◽

Sylvain Gandon

Keyword(s):

Life History ◽

Evolutionary Dynamics ◽

Fitness Landscape ◽

Adaptive Dynamics ◽

Life History Evolution ◽

Demographic Stochasticity ◽

Finite Populations ◽

Evolutionary Forces ◽

Pathogen Fitness ◽

History Evolution

The theory of life-history evolution provides a powerful framework to understand the evolutionary dynamics of pathogens. It assumes, however, that host populations are large and that one can neglect the effects of demographic stochasticity. Here, we expand the theory to account for the effects of finite population size on the evolution of pathogen virulence. We show that demographic stochasticity introduces additional evolutionary forces that can qualitatively affect the dynamics and the evolutionary outcome. We discuss the importance of the shape of the pathogen fitness landscape on the balance between mutation, selection and genetic drift. This analysis reconciles Adaptive Dynamics with population genetics in finite populations and provides a new theoretical toolbox to study life-history evolution in realistic ecological scenarios.

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Spatial selection and local adaptation jointly shape life-history evolution during range expansion

10.1101/031922 ◽

2015 ◽

Cited By ~ 2

Author(s):

Katrien Van Petegem ◽

Jeroen Boeye ◽

Robby Stoks ◽

Dries Bonte

Keyword(s):

Life History ◽

Local Adaptation ◽

Range Expansion ◽

Life History Traits ◽

Evolutionary Dynamics ◽

Life History Evolution ◽

Range Shifts ◽

Evolutionary Processes ◽

Spatial Selection ◽

History Evolution

In the context of climate change and species invasions, range shifts increasingly gain attention because the rates at which they occur in the Anthropocene induce fast shifts in biological assemblages. During such range shifts, species experience multiple selection pressures. Especially for poleward expansions, a straightforward interpretation of the observed evolutionary dynamics is hampered because of the joint action of evolutionary processes related to spatial selection and to adaptation towards local climatic conditions. To disentangle the effects of these two processes, we integrated stochastic modeling and empirical approaches, using the spider mite Tetranychus urticae as a model species. We demonstrate considerable latitudinal quantitative genetic divergence in life-history traits in T. urticae, that was shaped by both spatial selection and local adaptation. The former mainly affected dispersal behavior, while development was mainly shaped by adaptation to the local climate. Divergence in life-history traits in species shifting their range poleward can consequently be jointly determined by fast local adaptation to the environmental gradient and contemporary evolutionary dynamics resulting from spatial selection. The integration of modeling with common garden experiments provides a powerful tool to study the contribution of these two evolutionary processes on life-history evolution during range expansion.

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Species interactions and contemporary evolution

The Evolutionary Biology of Species ◽

10.1093/oso/9780198749745.003.0008 ◽

2019 ◽

pp. 148-166

Author(s):

Timothy G. Barraclough

Keyword(s):

Gene Flow ◽

Environmental Change ◽

Species Interactions ◽

Evolutionary Dynamics ◽

Contemporary Evolution ◽

Interacting Species ◽

As Species ◽

Species Shift ◽

Tree Holes ◽

Strength Of Competition

All organisms live within a diverse assemblage of many other species. Even with strict boundaries to gene flow, species interact in ways that shape their evolutionary dynamics. This chapter outlines how species interactions affect evolution of constituent species within a community. Models of competitive communities illustrate how interactions can constrain evolution, as species shift to occupy new regions with conditions similar to those they were previously adapted to. In contrast, coevolutionary interactions can stimulate evolution and amplify responses to environmental change. Experimental evolution on bacteria isolated from tree-holes formed by the roots of beech trees shows how species adapt to the presence of other species, leading to a decline in the strength of competition. Much more work is needed to investigate these effects in model assemblages of interacting species.

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Life history evolution in response to changes in metapopulation structure in an arthropod herbivore

10.1101/021683 ◽

2015 ◽

Author(s):

Annelies De Roissart ◽

Nicky Wybouw ◽

David Renault ◽

Thomas Van Leeuwen ◽

Dries Bonte

Keyword(s):

Life History ◽

Life History Traits ◽

Evolutionary Dynamics ◽

Life History Evolution ◽

Spatial And Temporal Variation ◽

Metapopulation Structure ◽

Significant Divergence ◽

Adaptive Stress Response ◽

Resource Shortage ◽

Dynamics Of Populations

The persistence and dynamics of populations largely depends on the way they are configured and integrated into space and the ensuing eco-evolutionary dynamics. We manipulated spatial and temporal variation in patch size in replicated experimental metapopulations of the herbivore mite Tetranychus urticae. Evolution over approximately 30 generations in the spatially and spatiotemporally variable metapopulations induced a significant divergence in life history traits, physiological endpoints and gene expression, but also a remarkable convergence relative to the stable reference patchy metapopulation in traits related to size and fecundity and in its transcriptional regulation. The observed evolutionary dynamics are tightly linked to demographic changes, more specifically frequent episodes of resource shortage, and increased the reproductive performance of mites on tomato, a challenging host plant. This points towards a general, adaptive stress response in stable spatial variable and spatiotemporal variable metapopulations that pre-adapts a herbivore arthropod to novel environmental stressors.

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The importance and adaptive value of life history evolution for metapopulation dynamics

10.1101/179234 ◽

2017 ◽

Author(s):

Dries Bonte ◽

Quinten Bafort

Keyword(s):

Life History ◽

Evolutionary Dynamics ◽

Local Density ◽

Life History Evolution ◽

Individual Performance ◽

Structured Populations ◽

Metapopulation Dynamics ◽

Systems Modelling ◽

Metapopulation Persistence ◽

History Evolution

1. The spatial configuration and size of patches influence metapopulation dynamics by altering colonisation-extinction dynamics and local density-dependency. This spatial forcing as determined by the metapopulation typology then imposes strong selection pressures on life history traits, which will in turn feedback on the ecological metapopulation dynamics. Given the relevance of metapopulation persistence for biological conservation, and the potential rescuing role of evolution, a firm understanding of the relevance of these eco-evolutionary processes is essential. 2. We here follow a systems modelling approach to quantify the importance of spatial forcing and experimentally observed life history evolution for metapopulation demography as quantified by (meta)population size and variability. We therefore developed an individual based model matching an earlier experimental evolution with spider mites to perform virtual translocation and invasion experiments that would have been otherwise impossible to conduct. 3. We show that (1) metapopulation demography is more affected by spatial forcing than by life history evolution, but that life history evolution contributes substantially to changes in local and especially metapopulation-level population sizes, (2) extinction rates are minimised by evolution in classical metapopulations, and (3) evolution is optimising individual performance in metapopulations when considering the importance of more cryptic stress resistance evolution. 4. Ecological systems modelling opens up a promising avenue to quantify the importance of eco-evolutionary feedbacks for larger-scale population dynamics. Metapopulation sizes are especially impacted by evolution but its variability is mainly determined by the spatial forcing. 5. Eco-evolutionary dynamics can increase the persistence of classical metapopulations. The maintenance of evolutionary dynamics in spatially structured populations is thus not only essential in the face of environmental change; it also generates feedbacks that impact metapopulation persistence.

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