Of all the mammalian species thought to have become extinct since the year 1500, about one-third have at some stage been rediscovered.

Diana Fisher and Simon Blomberg at the University of Queensland in Brisbane, Australia, examined the scientific literature and compared past and present Red Lists of threatened species compiled by the International Union for Conservation of Nature. The authors' analysis revealed that animal species that have suffered habitat loss are more likely to be rediscovered than those that have become extinct owing to over-hunting, or introduced predators or disease.

Furthermore, iconic species such as the Tasmanian tiger (Thylacinus cynocephalus) are searched for more frequently — and with less success — than less-iconic animals, such as the Australian lesser stick-nest rat (Leporillus apicalis), which may still exist.

Proc. R. Soc. B doi:10.1098/rspb.2010.1579 (2010)