 For example, a study conducted on a population of South African cheetahs demonstrated that the lack of genetic variability among individuals in the population has resulted in negative consequences for individuals, such as a greater rate of juvenile mortality and spermatozoal abnormalities.When heterozygotes possess a fitness advantage relative to a homozygote, a population with a large number of homozygotes will have a relatively reduced fitness, thus leading to inbreeding depression.Through these described mechanisms, the effects of inbreeding depression are often severe enough to cause the evolution of inbreeding avoidance mechanisms.