Post by DinosaurMichael on Nov 30, 2013 19:26:21 GMT 5
Jaguar - Panthera onca
The jaguar (/?d?æ?w?r/ or UK /?d?æ?ju?.?r/) is a big cat, a feline in the Panthera genus, and is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest in the Western Hemisphere. The jaguar's present range extends from Southern United States and Mexico across much of Central America and south to Paraguay and northern Argentina. Apart from a known and possibly breeding population in Arizona (southeast of Tucson), the cat has largely been extirpated from the United States since the early 20th century. This spotted cat most closely resembles the leopard physically, although it is usually larger and of sturdier build and its behavioural and habitat characteristics are closer to those of the tiger. While dense rainforest is its preferred habitat, the jaguar will range across a variety of forested and open terrain. It is strongly associated with the presence of water and is notable, along with the tiger, as a feline that enjoys swimming. The jaguar is largely a solitary, opportunistic, stalk-and-ambush predator at the top of the food chain (an apex predator). It is a keystone species, playing an important role in stabilizing ecosystems and regulating the populations of the animals it hunts. The jaguar has an exceptionally powerful bite, even relative to the other big cats. This allows it to pierce the shells of armoured reptiles and to employ an unusual killing method: it bites directly through the skull of prey between the ears to deliver a fatal bite to the brain. The jaguar is a compact and well-muscled animal. There are significant variations in size and weight: weights are normally in the range of 56–96 kilograms (124–211 lb). Larger males have been recorded at as much as 160 kg (350 lb) (roughly matching a tigress or lioness), and the smallest females have low weights of 36 kg (79 lb). Females are typically 10–20% smaller than males. The length of the cat varies from 1.2 to 1.95 m (3.9 to 6.4 ft), and its tail may add a further 45 to 75 cm (18 to 30 in). It stands about 63 to 76 cm (25 to 30 in) tall at the shoulders. Like the slightly smaller Old World leopard, this cat is relatively short and stocky in build. Further variations in size have been observed across regions and habitats, with size tending to increase from the north to south. A study of the jaguar in the Chamela-Cuixmala Biosphere Reserve on the Mexican Pacific coast, showed ranges of just about 50 kilograms (110 lb), about the size of the cougar. By contrast, a study of the Jaguar in the Brazilian Pantanal region found average weights of 100 kilograms (220 lb) and weights of 136 kilograms (300 lb) or more are not uncommon in old males. Forest jaguars are frequently darker and considerably smaller than those found in open areas (the Pantanal is an open wetland basin), possibly due to the smaller numbers of large herbivorous prey in forest areas. A short and stocky limb structure makes the jaguar adept at climbing, crawling and swimming. The head is robust and the jaw extremely powerful. The jaguar has the strongest bite of all felids, capable of biting down with 2,000 pounds-force (8,900 N). This is twice the strength of a lion and the second strongest of all mammals after the spotted hyena; this strength is an adaptation that allows the jaguar to pierce turtle shells. A comparative study of bite force adjusted for body size ranked it as the top felid, alongside the clouded leopard and ahead of the lion and tiger. It has been reported that "an individual jaguar can drag a 360 kg (800 lb) bull 8 m (25 ft) in its jaws and pulverize the heaviest bones". The jaguar hunts wild animals weighing up to 300 kilograms (660 lb) in dense jungle, and its short and sturdy physique is thus an adaptation to its prey and environment. The base coat of the jaguar is generally a tawny yellow, but can range to reddish-brown and black. The cat is covered in rosettes for camouflage in its jungle habitat. The spots vary over individual coats and between individual Jaguars: rosettes may include one or several dots, and the shape of the dots varies. The spots on the head and neck are generally solid, as are those on the tail, where they may merge to form a band. The underbelly, throat and outer surface of the legs and lower flanks are white. While the jaguar closely resembles the leopard, it is sturdier and heavier, and the two animals can be distinguished by their rosettes: the rosettes on a jaguar's coat are larger, fewer in number, usually darker, and have thicker lines and small spots in the middle that the leopard lacks. Jaguars also have rounder heads and shorter, stockier limbs compared to leopards.
Thylacosmilus - Thylacosmilus atrox
Thylacosmilus ("pouch sabre") was a genus of sabre-toothed metatherian predators that first appeared during the Miocene. Remains of the animal have been found in parts of South America, primarily Argentina. Though Thylacosmilus is one of several predatory mammal genera typically called "sabre-toothed cats", it was not a felid but a sparassodont, a group closely related to marsupials, and only superficially resembled other sabre-toothed mammals due to convergent evolution. Thylacosmilus had long, sabre-like upper canines and short, blunt, peg-like lower canines. The incisors were missing altogether and the other teeth were severely reduced, but, as distinct from machairodonts, their number was complete. It is estimated to have weighed around 150 kilograms (330 lb). Thylacosmilus and the similarly sized Marsupial Lion were the largest carnivorous metatherians. Thylacosmilus' sabre-teeth kept growing throughout its life, unlike those of true sabre-toothed felines. It also had a pair of elongated, scabbard-like flanges growing from the lower jaw, which protected the sabre-teeth when it closed its mouth. The cervical vertebrae were very strong and to some extent resembled the vertebrae of machairodonts. Thylacosmilus went extinct during the Pliocene, a timeframe closely corresponding to the arrival of the sabre-toothed cat Smilodon from North America in the Great American Interchange. Out-competition from the anatomically similar Smilodon appears to have driven the extinction, though this is not typical of other South American extinctions during the period.
The jaguar (/?d?æ?w?r/ or UK /?d?æ?ju?.?r/) is a big cat, a feline in the Panthera genus, and is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest in the Western Hemisphere. The jaguar's present range extends from Southern United States and Mexico across much of Central America and south to Paraguay and northern Argentina. Apart from a known and possibly breeding population in Arizona (southeast of Tucson), the cat has largely been extirpated from the United States since the early 20th century. This spotted cat most closely resembles the leopard physically, although it is usually larger and of sturdier build and its behavioural and habitat characteristics are closer to those of the tiger. While dense rainforest is its preferred habitat, the jaguar will range across a variety of forested and open terrain. It is strongly associated with the presence of water and is notable, along with the tiger, as a feline that enjoys swimming. The jaguar is largely a solitary, opportunistic, stalk-and-ambush predator at the top of the food chain (an apex predator). It is a keystone species, playing an important role in stabilizing ecosystems and regulating the populations of the animals it hunts. The jaguar has an exceptionally powerful bite, even relative to the other big cats. This allows it to pierce the shells of armoured reptiles and to employ an unusual killing method: it bites directly through the skull of prey between the ears to deliver a fatal bite to the brain. The jaguar is a compact and well-muscled animal. There are significant variations in size and weight: weights are normally in the range of 56–96 kilograms (124–211 lb). Larger males have been recorded at as much as 160 kg (350 lb) (roughly matching a tigress or lioness), and the smallest females have low weights of 36 kg (79 lb). Females are typically 10–20% smaller than males. The length of the cat varies from 1.2 to 1.95 m (3.9 to 6.4 ft), and its tail may add a further 45 to 75 cm (18 to 30 in). It stands about 63 to 76 cm (25 to 30 in) tall at the shoulders. Like the slightly smaller Old World leopard, this cat is relatively short and stocky in build. Further variations in size have been observed across regions and habitats, with size tending to increase from the north to south. A study of the jaguar in the Chamela-Cuixmala Biosphere Reserve on the Mexican Pacific coast, showed ranges of just about 50 kilograms (110 lb), about the size of the cougar. By contrast, a study of the Jaguar in the Brazilian Pantanal region found average weights of 100 kilograms (220 lb) and weights of 136 kilograms (300 lb) or more are not uncommon in old males. Forest jaguars are frequently darker and considerably smaller than those found in open areas (the Pantanal is an open wetland basin), possibly due to the smaller numbers of large herbivorous prey in forest areas. A short and stocky limb structure makes the jaguar adept at climbing, crawling and swimming. The head is robust and the jaw extremely powerful. The jaguar has the strongest bite of all felids, capable of biting down with 2,000 pounds-force (8,900 N). This is twice the strength of a lion and the second strongest of all mammals after the spotted hyena; this strength is an adaptation that allows the jaguar to pierce turtle shells. A comparative study of bite force adjusted for body size ranked it as the top felid, alongside the clouded leopard and ahead of the lion and tiger. It has been reported that "an individual jaguar can drag a 360 kg (800 lb) bull 8 m (25 ft) in its jaws and pulverize the heaviest bones". The jaguar hunts wild animals weighing up to 300 kilograms (660 lb) in dense jungle, and its short and sturdy physique is thus an adaptation to its prey and environment. The base coat of the jaguar is generally a tawny yellow, but can range to reddish-brown and black. The cat is covered in rosettes for camouflage in its jungle habitat. The spots vary over individual coats and between individual Jaguars: rosettes may include one or several dots, and the shape of the dots varies. The spots on the head and neck are generally solid, as are those on the tail, where they may merge to form a band. The underbelly, throat and outer surface of the legs and lower flanks are white. While the jaguar closely resembles the leopard, it is sturdier and heavier, and the two animals can be distinguished by their rosettes: the rosettes on a jaguar's coat are larger, fewer in number, usually darker, and have thicker lines and small spots in the middle that the leopard lacks. Jaguars also have rounder heads and shorter, stockier limbs compared to leopards.
Thylacosmilus - Thylacosmilus atrox
Thylacosmilus ("pouch sabre") was a genus of sabre-toothed metatherian predators that first appeared during the Miocene. Remains of the animal have been found in parts of South America, primarily Argentina. Though Thylacosmilus is one of several predatory mammal genera typically called "sabre-toothed cats", it was not a felid but a sparassodont, a group closely related to marsupials, and only superficially resembled other sabre-toothed mammals due to convergent evolution. Thylacosmilus had long, sabre-like upper canines and short, blunt, peg-like lower canines. The incisors were missing altogether and the other teeth were severely reduced, but, as distinct from machairodonts, their number was complete. It is estimated to have weighed around 150 kilograms (330 lb). Thylacosmilus and the similarly sized Marsupial Lion were the largest carnivorous metatherians. Thylacosmilus' sabre-teeth kept growing throughout its life, unlike those of true sabre-toothed felines. It also had a pair of elongated, scabbard-like flanges growing from the lower jaw, which protected the sabre-teeth when it closed its mouth. The cervical vertebrae were very strong and to some extent resembled the vertebrae of machairodonts. Thylacosmilus went extinct during the Pliocene, a timeframe closely corresponding to the arrival of the sabre-toothed cat Smilodon from North America in the Great American Interchange. Out-competition from the anatomically similar Smilodon appears to have driven the extinction, though this is not typical of other South American extinctions during the period.
