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

Abstract

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.

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

“…Relative to HOM, spatiotemporal variation in habitat availability in the classical metapopulations (TEM) generated high levels of local variation in population density and on average lower metapopulation sizes due to frequent patch extinctions and lagged colonization dynamics (De Roissart et al . ). Mites evolving in these metapopulations showed a significant down‐regulation of transcription of genes associated with gluconeogenesis and ATP production (Fig.…”

“…Mainland–island metapopulations (SPA) are characterized by both a low local and metapopulation‐level variability in population size, large metapopulation sizes and low metapopulation‐level dispersal (De Roissart et al . ). We detected no such pattern at the individual level.…”

“…We earlier documented how this variation in spatial structure affected demographic changes (De Roissart et al . ) and now report on the evolutionary phenomic changes as measured at the end of that experiment. Following the observed changes in demography and theoretical expectations outlined above, we predicted that:…”

Eco‐evolutionary dynamics in fragmented landscapes

“…). Standardized protocols in fragmented microcosms have been developed (Altermatt et al ), but they are restricted to the study of small organisms like protists or mites (Schtickzelle et al , De Roissart et al ). The Metatron platform has recently been built to offer such experimental facilities under semi‐natural conditions for larger terrestrial organisms at a meso‐scale (Legrand et al , , Bestion et al ).…”

Evolution during population spread affects plant performance in stressful environments

“…If traits promoting spread are positively correlated with performance under stress, evolutionary change during spread should enhance the ability of the population to expand into unfavourable locations. For example, spatiotemporal variation in patch size, which characterizes some invaded landscapes, may select for a general stress resistance response (De Roissart, Wybouw, Renault, Van Leeuwen, & Bonte, ). By contrast, negative correlations between traits promoting spread and performance under stress should cause evolution during spread through favourable habitat to inhibit further range expansion into harsh environments.…”