MOVINGTREES · Tree range dynamics under changing climates: a new modelling framework for reconstructing the past and predicting the future

Tree range dynamics under changing climates: a new modelling framework for reconstructing the past and predicting the future

Climate change is considered a major threat to biodiversity and ecosystem services at present. We are urged to anticipate the impacts in order to attempt mitigation, but reliable forecasts of the future dynamics of biodiversity are elusive. Despite intense research in the last decades, we are still lacking a comprehensive framework to understand and predict species responses to climate change. In this regard, one of the most promising research lines is the thorough investigation of the ecological and evolutionary consequences of past climate changes. Retrospective studies can provide key insights based on a better knowledge of biodiversity responses to past climate changes. To date, this retrospective knowledge has mostly been based on the fossil record, genetic data (phylogeography) and hindcasting of species distribution models. Despite the invaluable contributions of these approaches, all of them suffer from particular biases and assumptions that limit the reach of their inferences and preclude further understanding. For instance, accurate migration rates, persistence of rear-edge populations, or location of cryptic refugia are difficult to obtain at large (continental) scales by any of these methods. A rigorous way to overcome this problem is to integrate multiple data sources into a single statistical framework that jointly exploits all the available information and explicitly accounts for the biases and intrinsic limitations of different disciplines. Upon this rationale, we have developed a dynamic, process-based model of species range dynamics that, by means of Bayesian data assimilation, integrates information from the fossil record, palaeoclimate, phylogeography and species distribution data to reconstruct the range dynamics of species in relation to climate change since the Last Glacial Maximum (c. 21000 years ago). This quantitative framework is enabling us to better understand how European trees responded to past climate changes in terms of migration, regional extinction or persistence in previously unknown refugia. Importantly, the framework also enables fully probabilistic forecasting of expected distribution changes based on species’ past range dynamics and ecological features. Hence, integrative reconstructions of the past represent a promising way to promote ecological understanding and improve forecasts of climate change impacts on Earth’s biodiversity. Contact details: Dr. Francisco Rodriguez-Sanchez (frodriguez.work@gmail.com) Dr. David Coomes (David.Coomes@plantsci.cam.ac.uk) Dr. Drew Purves (dpurves@microsoft.com)

Data: CORDIS, © European Union