Historic climate change events can have a lasting impact on the genetic diversity of a species, reveals a new study published in Current Biology. This unexpected finding emerged from an analysis of the alpine marmot’s genome.
An iconic animal known to tourists and mountaineers, the alpine marmot is a large rodent exquisitely adapted to cold climates. Since the disappearance of its ice-age habitat, the alpine marmot has resided in high-altitude meadows in the Alps.
In this new study co-led by the Francis Crick Institute, an international team of scientists sequenced the genomes of alpine marmots living in three sites in the French and Italian Alps, and found that the animal’s genetic diversity is among the lowest of wild mammals. By reconstructing the marmot’s genetic past with the help of fossil records, they discovered that it lost its genetic diversity during the last ice age as a consequence of multiple climate related adaptations.
“We would not have expected the genetic diversity of alpine marmots to be so low,” says Toni Gossmann, first-author of the paper and researcher at the University of Sheffield and Bielefeld University in Germany. “They have a large population size, and we found little genetic evidence of inbreeding. But ironically, the very adaptations that helped them survive have trapped them in a state of low genetic diversity.”