Objectif
Long distance dispersal and adaptive radiation events have produced some of the most species rich ecosystems in the world. While colonizing lineages can adapt to new environments, the selective processes by which they do so is unclear given the paucity of genetic diversity in founder populations. Recent interest in the evolutionary role of transposable elements suggests they may contribute in generating genetic diversity through structural variation, doing so faster than the rate of background mutation. Despite research to date, evidence for exact mechanisms of transposable element mediated adaptive evolution is sparse. To address this, I propose to study a radiating clade of Diospyros (Ebenaceae) species on New Caledonia, a biodiversity hotspot. Following a long distance dispersal event, ca 30 species form an adaptive radiation and have larger genome sizes than congeners that arrived independently on the archipelago. Previous work has suggested that the divergence within the radiating lineage was driven largely by edaphic specialisation occurring independently multiple times. Here, I plan to investigate whether genes involved in adaptation to soil type are associated with structural variants, and whether these variants are mediated by transposable element activity. I will use three pairs of sister species, each of which is adapted to either fertile volcanic or poor ultramafic soils, enabling me to test for repeated patterns of adaptive evolution. This action will shed light on the potentially crucial but poorly understood contribution of transposable elements to adaptation, speciation, and biodiversity. Moreover, this work will provide understanding of the adaptive limits of different lineages in the face of ecological upheavals, relevant in the present context of environmental challenges.
Champ scientifique
Programme(s)
- HORIZON.1.2 - Marie Skłodowska-Curie Actions (MSCA) Main Programme
Régime de financement
MSCA-PF - MSCA-PFCoordinateur
1010 Wien
Autriche