Data from: The perils of paradise: an endangered species conserved on an island loses antipredator behaviours within 13 generations

When imperilled by a threatening process, the choice is often made to
conserve threatened species on offshore islands that typically lack the
full suite of mainland predators. Whilst keeping the species extant, this
releases the conserved population from predator-driven natural selection.
Antipredator traits are no longer maintained by natural selection and may
be lost. It is implicitly assumed that such trait loss will happen slowly,
but there are few empirical tests. In Australia, northern quolls (Dasyurus
hallucatus) were moved onto a predator-free offshore island in 2003 to
protect the species from the arrival of invasive cane toads on the
mainland. We compared the antipredator behaviours of wild-caught quolls
from the predator-rich mainland to those from this predator-free island.
We compared the responses of both wild-caught animals and their
captive-born offspring, to olfactory cues of two of their major predators
(feral cats and dingoes). Wild-caught, mainland quolls recognised and
avoided predator scents, as did their captive-born offspring. Island
quolls, isolated from these predators for only 13 generations, showed no
recognition or aversion to these predators. This study suggests that
predator aversion behaviours can be lost very rapidly, and that this may
make a population unsuitable for reintroduction to a predator-rich
mainland.