Fossil evidence shows that cheetahs may have originated in North America as early as 3 million years ago and then spread into Eurasia and Africa. Scientists found that around 12,000 years ago a significant climate change caused a rapid decline in the cheetah population. Overhunting and habitat destruction place cheetahs at high risk for extinction. Farmers often kill cheetahs to prevent them from threatening their livestock.
Scientists study cheetahs in the wild by using radio tracking, in which a collar with a radio transmitter attached is placed around the neck of a cheetah. Scientists monitor the radio transmissions as the cheetah travels in order to track the cat’s whereabouts and learn about its life history and behaviors.
Cheetahs are well adapted to dry habitats such as savanna grasslands and semideserts. They can survive for long periods without water. Although their populations were greatly reduced during the 20th century, as the 21st century began cheetahs still inhabited a broad section of Africa, including areas of the Sahel, East Africa, and southern Africa. Namibia has the largest population of cheetahs, with about 2,500 of them.
The name cheetah comes from the Hindu word chita, meaning “spotted one”, a reference to the cheetah’s light brown to tawny yellow skin colour. The spots change into a band pattern on the end of the tail that is distinctive in each cat.
Adult cheetahs measure 112 to 140 cm (44 to 55 in) from head to rear end and stand 66 to 94 cm (26 to 37 in) at the shoulder. A long tail extends 61 to 79 cm (24 to 31 in) in length. Cheetahs usually weigh around 39 to 65 kg (86 to 143 lb). Male cheetahs are generally bigger than females.
All cats are speedy runners, but the physical features adapted for speed are developed to the extreme in cheetahs. The long tail acts as a rudder to maintain balance at high speeds. Enlarged nasal and sinus passages,lungs and oversized heart support the extensive oxygen exchange needed during fast runs.
The cheetah has a small skull with a short muzzle, and its jaw is weaker than the jaws of other big cats. Cheetahs have 30 teeth, 15 on each side of the mouth. Their teeth are relatively smaller than those of other cats, leaving more room for the expanded nasal passages that help cheetahs run at such faster speeds. Cheetahs have excellent vision. Cheetah uses its vision and its acute sense of hearing and smell to locate and track prey.
Cubs are blind and helpless at birth, weighing around 250 to 300 g (9 to 10 oz). Long gray hairs, appear on the neck, shoulders, and back soon after birth and disappear at about three months. The cubs stay hidden in a den for about eight weeks, and the mother is extremely careful to avoid attracting predators to the den. She must be away for up to 48 hours while hunting, and predators often prey on her cubs while she is absent. At about eight weeks, cubs begin to accompany their mother as she hunts, and they partake in eating the meat of her kills. Nursing ends when cubs are about 4 months of age. Very young cubs begin to practice hunting through play behavior. The cubs stalk, chase, and wrestle with one another, and they will even chase prey that they know they cannot catch. Cubs do not become proficient hunters until they are about 24 months old. Young leave their mother at 13 to 20 months of age.
Female cheetahs reach sexual maturity when they are about 24 months old, while males do not become sexually mature until they are around 30 to 36 months old. Once they reach adulthood, cheetahs may live up to 12 years in the wild and up to 16 years in zoos. Most wild cheetahs do not live as long as 12 years, because they are frequently preyed upon by lions, hyenas, wild dogs, and leopards. In Tanzania’s Serengeti National Park, about 90 percent of all cubs die before they are three months old, and half of these deaths are due to predation. The period between leaving the mother and reaching adulthood is also dangerous, especially for males.
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