Biodiversity inhibits species’ evolutionary responses to changing environments

TLDR

Biodiversity’s influence on within‑species evolutionary dynamics is understudied despite growing ecological‑evolutionary research. The study uses a classical phenotypic evolution model in a patchy environment under global change to demonstrate that biodiversity can inhibit species’ evolution. A classical phenotypic evolution model in a patchy environment with global change affecting patch conditions is employed. Biodiversity increases the likelihood of pre‑adapted species, limiting evolutionary responses and favoring abundance shifts, which may explain niche conservatism and underscores the need to integrate ecological and evolutionary processes in diverse settings.

Abstract

Abstract Despite growing interplay between ecological and evolutionary studies, the question of how biodiversity influences evolutionary dynamics within species remains understudied. Here, using a classical model of phenotypic evolution in species occupying a patchy environment, but introducing global change affecting patch conditions, we show that biodiversity can inhibit species’ evolution during global change. The presence of several species increases the chance that one or more species are pre‐adapted to new conditions, which restricts the ecological opportunity for evolutionary responses in all the species. Consequently, environmental change tends to select for changes in species abundances rather than for changing phenotypes within each species. The buffering effects of species diversity that we describe might be one important but neglected explanation for widely observed niche conservatism in natural systems. Furthermore, the results show that attempts to understand biotic responses to environmental change need to consider both ecological and evolutionary processes in a realistically diverse setting.