OEB Seminar Series: Joana Meier
Date and Time
Location
Royal Society University Research Fellow and Group Leader
Wellcome Sanger Institute, Cambridge, UK
The roles of gene exchange and chromosomal rearrangements in rapid speciation
Abstract: Species richness is very unevenly distributed across the tree of life. While some lineages diversify rapidly into many species given ecological opportunity, others are much less prone to do so. For instance, one lineage of cichlid fishes repeatedly diversified into hundreds of species in each lake in the Lake Victoria region, whereas four other cichlid lineages that colonised the same lakes at the same time did not speciate. Here, I show that hybridisation facilitated the rapid diversification by providing ecologically relevant gene variants. Multiple cycles of hybridisation and diversification characterise the evolutionary history of the cichlid lineage that led to diversification into 500 species in just 16,000 years in the most recent radiation in Lake Victoria. Next, I explore if gene exchange generally facilitates rapid diversification and specifically, if it facilitated rapid adaptive radiation in certain lineages of South American butterflies. We find that in addition to gene exchange, chromosomal rearrangements play an important role. Complex chromosome fusions and fissions lead to reproductive isolation between closely related species in some lineages, likely facilitating their rapid adaptive radiations.
Host: OEB Postdoctoral Fellows