Tasmanian devil die-off is shifting another predator’s genetics

Devil population crashes caused by contagious tumours have knock-on effects elsewhere in the food chain.

Declining numbers of the endangered Tasmanian devil (Sarcophilus harrisii) are affecting the evolutionary genetics of a small predator, the spotted-tailed quoll (Dasyurus maculatus), according to a study published today in Nature Ecology & Evolution1.

The findings fit with what scientists would expect — typically, when a top predator’s population dwindles, smaller predators increase in number because there are more resources available and less competition.

But little is known about what the effect of a top predator’s decline is on the evolutionary genetics of other species in the food web, says study co-author Andrew Storfer, an evolutionary geneticist at Washington State University in Pullman. “This is one of the first studies to demonstrate that.”