Research published in Science Nov. 3 reveals that the first individuals settling on new land are more successful at passing on their genes than those who did not migrate. According to Dr. Damian Labuda at the University of Montréal and Sainte-Justine Hospital, the study suggests that population expansion creates opportunities for natural selection to act.
The findings come from the utilization of a unique research infrastructure, the BALSAC population database which allows the reconstruction of the structure of the Quebec population over four centuries. In this research the descending lineages of all couples married in the Charlevoix-Saguenay Lac St-Jean region between 1686 and 1960 were analyzed. This genealogy comprises more than 1 million individuals.
Dr. Laurent Excoffier, investigated the demographic history of this region to investigate the effects of rapid territorial and demographic expansion on the dynamics of colonization and human evolution.
“We find that families who are at the forefront of a range expansion into new territories had greater reproductive success. In other words, that they had more children, and more children who also had children,” Labuda explained. “As a result, these families made a higher genetic contribution to the contemporary population than those who remained behind in what we call the range core, as opposed to the wave front.