Around 75% of all mammals living in North America, Europe, and Australia disappeared when the ice age began 10,000-12,000 years ago. This made cheetahs nearly extinct, but a few of them survived and managed to continue the species to this day. In science, this is known as a population bottleneck. Cheetahs exist in a gene pool so small that the genetic variations among them can compare to those of deliberately inbred livestock.
This makes cheetahs virtual clones. There’s so much that can go wrong for these cats over time because of the lack of genetic diversity. It’s not easy for them to produce healthy offspring. Right now, the death rate of cheetahs in captivity in the U.S. and Canada exceeds the birth rate. The species has very high infant mortality rates — over 20% of infants born in captivity don’t live past six months, while the number for those born in the wild is around 70%, according to Smithsonian National Zoological Park.
Adult cheetahs are vulnerable to disease and the packs are prone to spreading various illnesses to each other.