After 13 generations isolated from predators, the northern quoll lost its fear of them
Conservationists are stuck in a catch-22: In trying to save some species, the would-be protectors may be giving the animals an evolutionary disadvantage. A new study describes how efforts to protect the endangered northern quoll, a spotted, kitten-sized marsupial native to Australia, by placing a population on a threat-free island may have actually undermined a key survival instinct.
After 13 generations — just 13 years — in isolation, the northern quolls (Dasyurus hallucatus) had lost their fear response to native predators, researchers report June 5 in Biology Letters.
“Evolution can happen very rapidly” for animals with fast breeding times, says evolutionary biologist Rick Shine of the University of Sydney, who was not involved in the study.
Separating endangered species from predators is a common conservation technique, sometimes taking