The promise and challenge of environmental epigenomics in a rapidly changing world

Rahia Mashoodh, Sinead English

There has been a fast-paced research effort on the role of epigenetic mechanisms in facilitating organisms’ capacity to cope with rapid environmental change, highlighted by several recent reviews and special issues on this topic. What is important, along with this momentum, is to pause and reflect on both the promises and challenges of linking detailed molecular mechanisms to broad patterns of population responses. Such reflection involves considering how different epigenetic mechanisms operate, depend on genomic context and taxonomic variation in function, the stability and persistence of epigenetic marks, and approaches to measuring these phenomena in natural populations. Here, we discuss in further detail these complexities, and in so doing bring a critical perspective on both the promise and limitations of studies considering epigenetic mechanisms as a driver of climate change adaptation. We provide practical suggestions for future studies that consider how both fundamental biology and methodological issues guide the design of ecological epigenomic studies. Collectively, we advocate for an interdisciplinary approach, where insights from molecular biology and evolutionary ecology, and close interaction between theoretical models and empirical tests, are important for advancing this field.