Kyoto, Japan -- For many endangered species, population decline to the brink of extinction leads to inbreeding, exposing a species to deleterious recessive mutations that severely limit its potential to recover. But the red-headed wood pigeon, endemic to the Ogasawara Islands in Japan, followed a different trajectory.

Although this pigeon population fell to below 80 individuals in the 2000s, it began to increase markedly after the removal of an introduced predator, the feral cat. Such a remarkable recovery raised questions regarding inbreeding, and why harmful mutations that could cause inbreeding depression, or a loss of genetic diversity, didn't hinder the species' revival.

In an effort to unravel this biological puzzle, a team of researchers at Kyoto University set out to investigate the factors that contributed to this unlikely comeback.