Lisa McManus, Rutgers University

Abstract

The adaptive potential of metapopulations under climate change will depend on both ecological and evolutionary processes that occur on complex networks. However, most work has assessed the population-level effects of these processes in isolation within a single patch or along relatively simple landscapes. We focus on corals as our study system, where populations can be linked across patches that are tens to thousands of kilometers apart through hydrodynamically driven larval dispersal. Here, we use an eco-evolutionary framework to quantify the relative contribution of dispersal and directional selection to coral adaptive potential across different types of coral reef seascapes. Within each patch, we modeled the competitive dynamics of three functional groups: a fast-growing coral, a stress-tolerant coral and macroalgae. We then simulated reef metacommunity dynamics under different temperature increase scenarios and quantified coral persistence within networks that can be classified as regular, random or small-world. We find that evolutionary capacity is the main driver of coral population persistence across all network types, such that coral populations are unable to persist without some genetic variation. We also show that larval production and seascape configuration are secondary drivers and thus modulate the effects of evolution on the ability of coral populations to persist under projected future warming. Though we specifically modeled coral reefs, our work broadly applies to other communities composed of a network of patches, especially those that are demographically linked by complex dispersal patterns.