Inbreeding and extinction in a butterfly metapopulation

It has been proposed that inbreeding contributes to the decline and eventual extinction of small and isolated populations1,2. There is ample evidence of fitness reduction due to inbreeding (inbreeding depression) in captivity3,4,5,6,7 and from a few experimental8,9 and observational field studies10,11, but no field studies on natural populations have been conducted to test the proposed effect on extinction. It has been argued that in natural...