Cheetah

The cheetah (Acinonyx jubatus) is a member of the cat family (Felidae) that is unique for making up in speed and stealth what it lacks in climbing abilities. As such, it is placed in its own genus, Acinonyx. It is the fastest of all land animals and can reach speeds between 112 kilometres per hour (70 mph) and 120 kilometres per hour (75 mph)[3] in short bursts up to 460 metres (500 yd), and has the ability to accelerate from 0 to 110 kilometres per hour (68 mph) in three seconds, faster than most supercars.[4]
The word "cheetah" is derived from the Sanskrit word chitrakaya?, meaning "variegated body", via the Hindi ???? cita.[5]
The cheetah's chest is deep and its waist is narrow. The coarse, short fur of the cheetah is tan with round black spots measuring from 2 centimetres (0.79 in) to 3 centimetres (1.2 in) across, affording it some camouflage while hunting. There are no spots on its white underside, but the tail has spots, which merge to form four to six dark rings at the end. The tail usually ends in a bushy white tuft. The cheetah has a small head with high-set eyes. Black "tear marks" run from the corner of its eyes down the sides of the nose to its mouth to keep sunlight out of its eyes and to aid in hunting and seeing long distances.
The adult cheetah weighs from 40 kilograms (88 lb) to 65 kilograms (140 lb). Its total body length is from 115 centimetres (45 in) to 135 centimetres (53 in), while the tail can measure up to 84 centimetres (33 in) in length. Males tend to be slightly larger than females and have slightly bigger heads, but there is not a great variation in cheetah sizes and it is difficult to tell males and females apart by appearance alone. Compared to a similarly-sized leopard, the cheetah is generally shorter-bodied, but is longer tailed and taller (it averages about 90 centimetres (35 in) tall) and so it appears more streamlined.
Some cheetahs also have a rare fur pattern mutation: cheetahs with larger, blotchy, merged spots are known as 'king cheetahs'. It was once thought to be a separate subspecies, but it is merely a mutation of the African cheetah. The 'king cheetah' has only been seen in the wild a handful of times, but it has been bred in captivity.
The cheetah's paws have semi-retractable claws[6] (known only in three other cat species - the Fishing Cat, the Flat-headed Cat and the Iriomote Cat) offering the cat extra grip in its high-speed pursuits. The ligament structure of the cheetah's claws is the same as those of other cats; it simply lacks the sheath of skin and fur present in other varieties, and therefore the claws are always visible, with the exception of the dewclaw. The dewclaw itself is much shorter and straighter than other cats.
Adaptations that enable the cheetah to run as fast as it does include large nostrils that allow for increased oxygen intake, and an enlarged heart and lungs that work together to circulate oxygen efficiently. During a typical chase its respiratory rate increases from 60 to 150 breaths per minute.[6] While running, in addition to having good traction due to its semi-retractable claws, the cheetah uses its tail as a rudder-like means of steering to allow it to make sharp turns, necessary to outflank prey who often make such turns to escape.
Unlike "true" big cats, the cheetah can purr as it inhales, but cannot roar. By contrast, the big cats can roar but cannot purr, except while exhaling. However, the cheetah is still considered by some to be the smallest of the big cats. While it is often mistaken for the leopard, the cheetah does have distinguishing features, such as the aforementioned long "tear-streak" lines that run from the corners of its eyes to its mouth. The body frame of the cheetah is also very different from that of the leopard, most notably so in its thinner and longer tail, and unlike the leopard, its spots are not arranged into rosettes.
The cheetah is a vulnerable species. Out of all the big cats, it is the least able to adapt to new environments. It has always proved difficult to breed in captivity, although recently a few zoos have been successful. Once widely hunted for its fur, the cheetah now suffers more from the loss of both habitat and prey.
The cheetah was formerly considered to be particularly primitive among the cats and to have evolved approximately 18 million years ago. New research, however puts the last common ancestor of all 40 existing species of feline more recently, at 11 million years. The same research indicates that the cheetah, while highly derived morphologically, is not a particularly ancient lineage, having separated from its closest living relatives (the cougar Puma concolor and the jaguarundi Puma yaguarondi) around 5 million years ago.[7][8]

Golden Lion Tamarin

The Golden Lion Tamarin (Leontopithecus rosalia) also known as Golden Marmoset, is a small New World monkey of the family Cebidae. Native to the Atlantic coastal forests of Brazil, the Golden Lion Tamarin is an endangered species and among the rarest animals in the world, with an estimated wild population of 1,000 individuals and a captive population of approximately 500.
As its name would suggest, this lion tamarin is a reddish orange to golden brown in colour. Its hair is longer and darker around the face, forming a mane on top of the head and on the cheeks and throat. Its limbs are slender yet capable with sharp claws, befitting its strictly arboreal life. Although quite long, its tail is not prehensile. The tail and forepaws of this monkey may have a black coloration. Its body may be up to 335 millimetres (13.2 in) long and its tail up to 400 millimetres (16 in). The male reaches a maximum weight of just 700 grams (25 oz) in the wild though higher weights can be found in captivity. The pregnant female may weigh up to 790 grams (28 oz) but a non-gestating female typically weighs closer to 550 grams (19 oz).
Most of the wild population is confined to the Poço das Antas Biological Reserve, a protected area of swampy forests in the state of Rio de Janeiro. It is an important bastion of the Golden Lion Tamarin, as only 2% of forests in the monkey's original range remains. Furthermore, its existing habitat has been broken up by logging and agriculture; this has led to isolated populations and inbreeding, a combination likely to result in extinction.
A high canopy with dense tangles of vines is required by the Golden Lion Tamarin; other than providing a home, the labyrinthine forest affords some degree of protection from its many predators. Its main predators are raptors, large cats and snakes. The canopy also provides an important source of food; the omnivorous lion tamarins rely on rainwater and insects concentrated in the reservoirs of bromeliads and other small animals inhabiting the bark of trees. Fruit is also eaten.

Wolverine

The wolverine (Gulo gulo) is the largest land-dwelling species of the Mustelidae or weasel family (the Giant Otter is largest overall), and is the only species currently classified in the genus Gulo (meaning "glutton"). It is also called the Glutton or Carcajou. Some authors recognize two subspecies: the Old World form Gulo gulo gulo and the New World form G. g. luscus. A third subspecies limited to Vancouver Island (G. g. vancouverensis) is also occasionally described. However craniomorphic evidence suggests that the Vancouver Island wolverines are properly included within G. g. luscus.
The wolverine is, like most mustelids, remarkably strong for its size. It has been known to kill prey as large as moose, although most typically when these are weakened by winter or caught in snowbanks.[4] Wolverines inhabiting the Old World (specifically, Fennoscandia) are more active hunters than their North American cousins.[5] This may be because competing predator populations are not as dense, making it more practical for the wolverine to hunt for itself than to wait for another animal to make a kill and then try to snatch it.
Armed with powerful jaws and a thick hide,[6] wolverines may defend kills against larger or more numerous predators.[7] There is at least one published account of a 27-pound wolverine's attempt to steal a kill from a much larger predator—namely, a black bear (adult males weigh 400 to 500 pounds). Unfortunately for the mustelid, the bear won what was ultimately a fatal contest, crushing the wolverine's skull.[8][9]
Mating season is in the summer, but the actual implantation of the embryo (blastocyst) in the uterus is stayed until early winter, delaying the development of the fetus. Females will often not produce young if food is scarce. The young (typically three or four) are born in the spring. Kits develop rapidly, reaching adult size within the first year of a lifespan that may reach anywhere from five to (in exceptional individuals) thirteen years.[9]
Adult wolverines have no natural predators, save man, though they do come into conflict with (and may be killed by) other large predators over territory and food. Juveniles are, unsurprisingly, more vulnerable and infants (kits) have been known on occasion to be taken by predatory birds, such as eagles.[10]

Gray Wolf

The gray wolf (Canis lupus), also known as the timber wolf or wolf, is a mammal of the order Carnivora. The gray wolf is the largest wild member of the Canidae family, with its shoulder height ranging from 0.6 to 0.9 meters (26–36 inches) and its weight varying between 32 and 62 kilograms (70–135 pounds). DNA sequencing and genetic drift studies indicate that the gray wolf shares a common ancestry with the domestic dog (Canis lupus familiaris).[2] A number of other gray wolf subspecies have been identified, though the actual number of subspecies is still open to discussion.
Human expansion has had a dramatic effect on wolves. Though once abundant over much of North America and Eurasia, the gray wolf inhabits a very small portion of its former range because of widespread destruction of its habitat, human encroachment of its habitat, and the resulting human-wolf encounters that sparked broad extirpation. Considered as a whole, however, the gray wolf is regarded as being of least concern for extinction according to the International Union for the Conservation of Nature and Natural Resources. Today, wolves are protected in some areas, hunted for sport in others, or may be subject to extermination as perceived threats to livestock and pets.
Gray wolves play an important role as apex predators in the ecosystems they typically occupy. Gray wolves are highly adaptable and have thrived in temperate forests, deserts, mountains, tundra, taiga, and grasslands.
Wolves have been featured in the folklore and mythology of many cultures throughout history. Norse mythology tells the legend of the giant Fenrir. More sympathetic depictions include the suckling of Romulus and Remus in the Roman creation story. Wolves have also appeared in Western fairy tales such as Little Red Riding Hood and the Three Little Pigs, in which the wolf plays the role of the villain.

Platypus

The Platypus (Ornithorhynchus anatinus) is a semi-aquatic mammal endemic to eastern Australia, including Tasmania. Together with the four species of echidna, it is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth to live young. It is the sole living representative of its family (Ornithorhynchidae) and genus (Ornithorhynchus), though a number of related species have been found in the fossil record.
The bizarre appearance of this egg-laying, venomous, duck-billed, beaver-tailed, otter-footed mammal baffled European naturalists when they first encountered it, with some considering it an elaborate fraud. It is one of the few venomous mammals; the male Platypus has a spur on the hind foot that delivers a poison capable of causing severe pain to humans. The unique features of the Platypus make it an important subject in the study of evolutionary biology and a recognizable and iconic symbol of Australia; it has appeared as a mascot at national events and is featured on the reverse of the Australian 20 cent coin.
Until the early 20th century it was hunted for its fur, but it is now protected throughout its range. Although captive breeding programs have had only limited success and the Platypus is vulnerable to the effects of pollution, it is not under any immediate threat.

Orca

The Orca or Killer Whale (Orcinus orca), less commonly, Blackfish or Seawolf, is the largest species of the oceanic dolphin family. It is found in all the world's oceans, from the frigid Arctic and Antarctic regions to warm, tropical seas.
Orcas are versatile and opportunistic predators. Some populations feed mostly on fish, and other populations hunt marine mammals, including sea lions, seals, and even large whales. There are up to five distinct Orca types, some of which may be separate subspecies or even species. Orcas are highly social; some populations are composed of matrilineal family groups which are the most stable of any animal species.[1] The sophisticated social behaviour, hunting techniques, and vocal behaviour of Orcas have been described as manifestations of culture.[2]
Although Orcas are not an endangered species, some local populations are considered threatened or endangered due to pollution, depletion of prey species, conflicts with fishing activities and vessels, habitat loss, and whaling. Wild Orcas are usually not considered a threat to humans.[3] There have, however, been isolated reports of captive Orcas attacking their handlers at marine theme parks.[4]
The Orca is an apex predator. They are sometimes called the wolves of the sea because they hunt in packs like wolves.[16] On average, an Orca eats 227 kg (500 lb) of food each day.[17]
Orcas prey on a diverse array of species. However, specific populations show a high degree of specialization on particular prey species. For example, some populations in the Norwegian and Greenland sea specialise in herring and follow that fish's migratory path to the Norwegian coast each autumn. Other populations in the area prey on seals. In field observations of the resident whales of the northeast Pacific, salmon accounted for 96% of animals' diet, with 65% of the salmon being the large, fatty Chinook.[1] They have been observed to swim through schools of the smaller salmon species without attacking any of them. Depletion of specific prey species in an area is therefore cause for concern for the local Orca population, despite the high overall diversity of potential Orca prey.
Although resident Orcas have never been observed to eat other marine mammals, they are known to occasionally harass and kill porpoises and seals for no apparent reason.[1]

Babirusa

The Babirusa or pig-deer, Babyrousa babyrussa, is a pig-like animal native to Sulawesi and surrounding islands of Indonesia. It has two pairs of large tusks; enlarged canine teeth that curve back up through the top of the snout. This species is considered endangered.
The babirusa has usually been classified as a single species in the genus Babyrousa, but recent work suggests that there may be several species, differentiable on the basis of geography, body size, amount of body hair, and the shape of the upper canine tooth of the male. Most experts agree that babirusas are part of the pig family, and are one of the oldest living members of the family, representing a subfamily, Babyrousinae, that branched off from the warthog branch of the pig family (Subfamily Phacochoerini) during the Oligocene or early Miocene.
The Babirusa is native to the large eastern Indonesian island of Sulawesi and surrounding islands. Its habitat is the underbrush of tropical forests and canebrakes, and the shores of rivers and lakes. Its mostly-hairless, mottled-grey-and-brown hide provide it with a degree of camouflage. The babirusa is known for its two pairs of tusks; both its upper and its lower pairs of canine teeth are greatly enlarged, and curve up and back towards the head. The upper canines of the male babirusa are so curved and enlarged that they emerge through the flesh, by way of holes, to pass through the top of the snout.
This species is on the endangered list.
Because it is split-hooved and has a three-chambered stomach (and was thus thought to be a ruminant for a long time), there was some dispute in Halakha (Jewish law) as to whether the babirusa pig is, in fact, kosher (permitted according to Jewish dietary laws). Eventually it was found that the animal is not a true ruminant, and thus remains 'trefe' like other pigs.