Macroecology and biogeography: effects of changing climates on biodiversity

Spatial explicit biogeographic scenarios across scales and times

These projects explore the effects of climate fluctuations on the distribution, ecological niche, and evolutionary history of organisms, mainly using various types of species distribution models (correlative, mechanistic, hybrid) and molecular analyses. Models are created that project the potential distribution of species under current, historical (e.g. Last Glacial Maximum, Mid-Holocene) and future climate scenarios (IPCC/SSP). We quantify how and where anthropogenic climate and land-use change may pose a significant threat, and if it leads to a reduction or displacement of suitable habitats or to fragmentation.

What can we learn about the adaptability of species?

The research line also investigates the dynamics and evolutionary capacities of species in terms of thier ecological niches. Especially in invasive species, an expansion of their realised climatic niche in their native range is frequently observed within an invaisve range, indicating on one hand an increased risk of invasion but also providing valuable insights into niche dynamics. On the other hand, the environmental niches of endemic species occupying rather small ranges tend to show rather patterns of niche conservatism accompanied by high degrees of specialisation. This may make them more susceptible to climate and land-use change. The projects within this research line investigate causal mechanisms behing these contrasting niche structures to derive general ecological, evolutionary and biogeographic mechanisms.

Tracking historical changes

The theoretical foundation and developed methods within our project allow various applications in e.g. biogeography and conservation science. Phylogeographic studies for example show that Quaternary climate fluctuations have shaped today's spatial genetic structure of taxa, often through refuge areas at lower latitudes, subsequent expansion and recolonisation. Here, the integration of genetic and ecological data is crucial to identify historical migration routes and to detect potential stable future refuges in need of increased natrue conservation efforts. The same is true when developing potential future scenarios for conservation planning, accounting for climate change and land-use change scenarios.