Perhaps for the cheetah, though, individual numbers of animals may not be the important poin, but the numbers of viable populations still existing. Viable populations may be found in only half or less of the countries where cheetahs still exist.
The cheetah has suffered a devastating decline of available habitat and prey, both necessary for its survival. Since then, they have faced pressure from climate change, habitat loss, and human activities. At the turn of the 19th century, more than , cheetahs are estimated to have been living in Africa, the Middle East, and elsewhere in Asia. Today, cheetahs are found in the wild in several locations in Africa, and a tiny population of another subspecies, the Asiatic cheetah, is found in Iran.
Scientists estimate that fewer than 8, African cheetahs are living in the wild today and that there may be fewer than 50 Asian cheetahs left in the world. These data reflect an overall decline of about 50 percent in the last four decades, as well as a significant shrinkage in the historic range of the species. Cheetahs today are heading toward extinction, though notably cheetahs have faced and overcome the threat of extinction before.
Genetic analysis of wild cheetahs shows they may have survived two historical bottlenecks, events that sharply reduce the size of a population. When this happens, the few remaining individuals end up inbreeding , or mating with relatives. Inbreeding reduces the size of the gene pool , which can lead to problems such as decreased genetic variability and the persistence of potentially harmful mutation s, making it harder for the remaining population to adapt to changes in their environment.
In a very small population, any mutations that occur are much more likely to be passed on to offspring and propagate through successive generations. The first bottleneck event that cheetahs may have undergone occurred around , years ago when cheetahs expanded their range into Asia, Europe, and Africa.
This range expansion is believed to have occurred rapidly, dispersing the cheetahs over a very large area and thus restricting their ability to exchange genes. The second likely bottleneck event occurred about 10, to 12, years ago, around the end of the last ice age.
In this bottleneck the cheetahs of North America and Europe went extinct, leaving extant only the species' Asian and African populations.
As large mammals died out across the world, the number of surviving cheetahs dwindled, which caused extreme inbreeding. Even though the number of cheetahs grew to as many as , during the 19th century, their genetic variability remained low due to the extreme bottleneck event that took place thousands of years previously. Present-day cheetah populations have relatively low genetic variability, evidence for which comes from several different indicators. One way to test for the degree of inbreeding is to perform a skin graft.
This involves transplanting a piece of skin from one cheetah onto another to see if the receiving cheetah accepts or rejects the graft. In inbred populations, skin grafts are easily accepted by individuals unrelated to the donor. This occurs among cheetahs, suggesting they have lost some genetic diversity. Another sign of inbreeding is asymmetrical skull development. In inbred animals, the skull is more asymmetrically shaped.
It gets as close to the prey as possible; then in a burst of speed, it tries to outrun its quarry. These big cats are the fastest of all land mammals. Once the cat closes in, it knocks the prey to the ground with its paw and suffocates the animal with a bite to the neck. Once it has made a kill, it eats quickly and keeps an eye out for scavengers—lions, leopards, hyenas, vultures, and jackals will steal from this timid predator.
The majority of hunts result in failure. The historic distribution of this species is very wide. But in the s, European settlers saw these big cats as vermin to be eradicated, and populations were widely reduced.
Currently, they only inhabit about 10 percent of their historic range. Their range occurs widely but is extremely sparse and fragmented in the regions they still inhabit. Southern and Eastern Africa are strongholds for cheetah populations. Unleash more canine heroes to save elephants. Donate now. Learn how we're protecting Africa's species each and every day so we never have to live in a world without elephants, rhinos, and other precious wildlife.
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