Increasing stress from human activities threatens the capacity of ecosystems to provide essential ecosystem services. Contemporary stressors such as climate change, increased nutrient loads and pollution can compromise the success of organisms and, ultimately, the functioning of whole ecosystems. An ecosystem’s response to stress will depend partly on how individual species adapt and interact with others. We must be able to predict these responses to manage or protect ecosystems that are affected by industry, agriculture or other human activities. This is a particularly challenging puzzle because of the interactions amongst sources of stress and the complex eco-evolutionary dynamics that follow after stress. This talk summarizes the results from recent studies exploring the evolutionary response of Anthropocene ecosystems to environmental change.
Results/Conclusions
While there is a clear expectation that the evolutionary response to environmental change be adaptive, studies conducted in natural ecosystem contexts frequently fail to produce adaptive responses. A sizeable number of studies either report the absence of adaptation (i.e., “eco”, not “eco-evo” dynamics) or even mal-adaptive evolutionary change. I will present some examples of such non- or mal-adaptive outcomes from my own and other labs and discuss how these unexpected results might have arisen in the context of ecosystem complexity. I will also present a simple, conceptual evolutionary model that can explain how evolutionary dynamics that seek to increase trait fitness in stressful environments can result in apparently maladaptive outcomes. In conclusion, this talk will provide evidence against the expectation that evolution in ecosystems always needs to be adaptive.