cross-posted from: https://europe.pub/post/16485236
Karure, the New Zealand’s black robin (petroica traversi) is an amazing story of how a species on the brink of extinction, with one breeding pair left, has now recovered to approximately 350 individuals in 2025. All of these individuals are descended from one female called Old Blue.
(Text from: https://www.sciencelearn.org.nz/images/old-blue-the-story-of-the-black-robin )
Unfortunately the very low genetic diversity of their only being a single pair means they could easily be wiped out from genetic mutations or sickness.
Yes, that’s certainly true. Most species that have nearly gone extinct face this bottleneck problem. That said, given a sufficiently long evolutionary timeframe, genetic diversity can develop again. I think it’s definitely better for the species to continue to exist (albeit in a greatly reduced form) than for it to be completely extinct… because then genetic diversity would truly be zero.