We thought inbred koalas were at risk of extinction. But what we discovered upends genetic conventions
Andrew Weeks, The University of Melbourne; Adam Miller, RMIT University; Collin Ahrens, Western Sydney University
Population crashes are dangerous and can be irreversible. But new research shows they are not always an evolutionary dead end.
Click on link to continue https://theconversation.cmail19.com/t/r-l-tkuisdk-olrclhtkj-jh/
The magazine Science
https://www.science.org/doi/10.1126/science.adz1430
Escaping bottlenecks: The demographic path to genetic recovery in koalas (Phascolarctos cinereus)
Editor’s summary
Population genetics theory predicts that bottlenecks, or times when abundance in a population crashes to a small number of individuals, can lead to an extinction vortex due to loss of genetic variation. Nonetheless, there are cases in nature where this process has occurred but the species has recovered. Ahrens et al. looked at populations of once widespread koalas across regions of Australia to determine how bottlenecks affected their diversity. They found that populations that had experienced reductions showed signs of recovery, such as increasing effective population size and reduced mutational load due to rapid demographic expansion. —Sacha Vignieri
