Eco-evolutionary Dynamics of Colonization: When Does Source Selection Matter?

The paper titled "Eco-evolutionary Dynamics of Colonization: When Does Source Selection Matter?" explores how the genetic makeup of ancestral populations affects the success of species colonization in new environments. The researchers used computer simulations to examine the impact of selection regimes in the source population on colonization success under various invasion scenarios and different selection conditions in the new habitat.

Balancing selection in ancestral populations was found to increase the likelihood of successful colonization compared to scenarios with source neutrality or directional selection, particularly when the founder populations were small, a situation that could arise after a population bottleneck. This effect held true regardless of whether the new habitat presented stable or variable conditions and persisted even under more challenging environmental conditions or greater environmental perturbations.

Conversely, when the colonizing populations were large, the influence of selection in the source population on invasion success diminished. The study underscores the importance of genetic diversity and propagule pressure on colonization success, emphasizing that the number of adaptive alleles is a critical metric. The findings reveal a complex interaction between genetic diversity and propagule pressure, shedding light on the unique role of balanced polymorphism in facilitating successful colonization.