The reintroduction of failed species:

A study warned of how sanctuaries for endangered species can stop these species from being afraid of their predators.

In 2003 Australia moved 64 Quolls, a small endangered marsupial to two islands free of predators with the aim of saving the species.

When after 13 generations had already been reproduced by thousands and were no longer in danger of extinction will try to introduce them to the continent, but something went wrong, the dingo wild dogs of Australia began to eat them with a disturbing ease and this study was set in this case he has found that unlike the Quolls that have survived on the continent the animals that lived on the islands do not have anti-predation mechanisms because they do not have predators after 13 generations without mediation of natural selection have stopped recognizing their predators and do not react to olfactory signals, a wake-up call for future species conservation projects.