Cheetahs are probably the most inbred species on the planet. They are so closely related to each other that organ transplants are not a problem as this article explains:
Will evolution doom the cheetah?
"If a cheetah needed a kidney transplant, it could probably get one from any other individual. Siblings, third cousins twice removed and even complete strangers on the other side of Africa could all probably donate a kidney to a fellow cheetah."
I have not read this particular article, but it is almost as if they have read my posts where I say the fact that you won't end up in a skid row motel in a bathtub full of ice missing a kidney tells us that the flood never happened. With a Noah's Ark level bottleneck we would be even more closely related than cheetahs. I can't find it now, but I swear that I did read in one article on them that their breeding population got down to around ten individuals at the worst of the bottleneck. Cheetahs still suffer today due to that extreme bottleneck and with humans messing up their hunting ranges they may go extinct yet.
There are some other species that had very few individuals left. Both the California Sea Otter and the European Bison or Wisent had populations that got down to about 50 individuals In the Wisent's case a breeding program was started to save as much genetic diversity as possible:
European bison - Wikipedia
It is so odd that there are so many totally independent sources of evidence that refute the flood myth and yet it lives on.