Cheetah

The cheetah (Acinonyx jubatus) is a large felid native to Africa and parts of Iran, famous for being the fastest land animal. But from the perspective of conservation biology, the cheetah is more significant as a case study in genetic load and the consequences of population bottleneck. The species experienced a severe genetic bottleneck approximately 10,000 years ago, and modern cheetahs show remarkably low genetic diversity — so low that skin grafts between unrelated individuals are accepted as if they were identical twins.

This genetic uniformity makes the cheetah exceptionally vulnerable to disease, environmental change, and inbreeding depression. It is a living demonstration that a population can be numerically large but genetically doomed — a counterexample to the naive assumption that headcount equals viability. The cheetah is the canary in the coal mine for the Sixth Mass Extinction: a species that looks healthy on the surface but is walking on a genetic tightrope.

See also: Conservation biology, Genetic load