Cheetahs are so inbred that two unrelated animals might seem genetically like identical twins!
About 10,000 years ago, all but one species of cheetah became extinct due to climate changes. There was a drastic reduction of that one species’ numbers and the remaining ones were forced to breed, even though they were close relatives. Since then, all cheetahs are closely related.
When you look at their gene composition, related cheetahs share about 99% of their genes, when in most species’ that number is about 80%. This lack of genetic diversity can cause a lot of problems, because it makes the species as a whole more susceptible to disease and less adaptable to new environments. This means that a single deadly virus could kill off all wild cheetahs in the world.
Learn more about this problem here