Hybridization facilitates evolutionary rescue

Evol Appl. 2014 Dec;7(10):1209-17. doi: 10.1111/eva.12214. Epub 2014 Sep 25.

Abstract

The resilience of populations to rapid environmental degradation is a major concern for biodiversity conservation. When environments deteriorate to lethal levels, species must evolve to adapt to the new conditions to avoid extinction. Here, we test the hypothesis that evolutionary rescue may be enabled by hybridization, because hybridization increases genetic variability. Using experimental evolution, we show that interspecific hybrid populations of Saccharomyces yeast adapt to grow in more highly degraded environments than intraspecific and parental crosses, resulting in survival rates far exceeding those of their ancestors. We conclude that hybridization can increase evolutionary responsiveness and that taxa able to exchange genes with distant relatives may better survive rapid environmental change.

Keywords: Saccharomyces; evolutionary rescue; extinction; genetic variation; global change; hybridization.