Résumé
Eco-evolutionary dynamics are predicted to involve feedback loops, where
ecological changes driven by rapid evolution feed back to shape further
evolution. However, direct experimental evidence for such loops in the
wild is lacking. Here, we show that eco-evolutionary dynamics in a
plant-feeding arthropod community involve a negative feedback loop.
Specifically, adaptation in cryptic coloration in an abundant stick-insect
species mediates bird predation, with local maladaptation increasing
predation. In turn, the abundance of arthropods is reduced by predation.
Here, we experimentally manipulate arthropod abundance to show that these
community-level changes feedback to affect stick-insect evolution.
Specifically, low arthropod abundance increases the strength of selection
on crypsis, increasing local adaptation of stick insects in a negative
feedback loop. Our results suggest that eco-evolutionary feedbacks are
able to stabilize complex systems by preventing consistent directional
change and therefore increasing resilience.