Speciation in action: divergent climate adaptation and genome clashes in hybrids

Climate adaptation should lead to coordinated changes in mitochondrial and nuclear (mitonuclear) DNA units, which underlay the biochemical machinery responsible for energy metabolism.

Population divergence in climate adaptation may therefore lead to speciation through hybrid dysfunction caused by mismatched mitonuclear DNA units, but empirical evidence remains rare.

To fill this knowledge gap, we will reveal specific allelic changes in interacting mitonuclear units underlying (1) divergent climate adaptation, and (2) hybrid dysfunction in two closely related species of birds.

We will collect (a) high-resolution data on energy metabolism, (b) blood samples for state-of the art genomic analyses, and (c) data on individual fitness performance under different environmental challenges during year 1-3.

Year 3-4, we will obtain sequence data from SciLifeLab and hypothesis driven pathway-based analytical (PBA) methods will be used to connect the obtained sources of information.

Taken together, we will test whether the same genetic variants that are responsible for differences in climate adaptation between the two species also cause mitonuclear clashes and reduced fitness in their hybrids.

This project thereby has an outstanding chance to uncover the ´holy grail´ in the field of speciation research, namely the possible connection between ecological divergence and the emergence of genetic incompatibilities.