The walrus (Odobenus rosmarus) is a large flippered marine mammal with a discontinuous distribution about the North Pole in the Arctic Ocean and subarctic seas of the Northern Hemisphere. The walrus is the only living species in the family Odobenidae and genus Odobenus. This species is subdivided into two subspecies:[2] the Atlantic walrus (O. r. rosmarus), which lives in the Atlantic Ocean, and the Pacific walrus (O. r. divergence), which lives in the Pacific Ocean.
Adult walrus is characterized by prominent tusks and whiskers, and their considerable bulk: adult males in the Pacific can weigh more than 2,000 kilograms (4,400 pounds)[3] and, among pinnipeds, are exceeded in size only by the two species of elephant seals.[4] Walruses live mostly in shallow waters above the continental shelves, spending significant amounts of their lives on the sea ice looking for benthic bivalve mollusks to eat. Walruses are relatively long-lived, social animals, and they are considered to be a "keystone species" in the Arctic marine regions.
The walrus has played a prominent role in the cultures of many indigenous Arctic peoples, who have hunted the walrus for its meat, fat, skin, tusks, and bone. During the 19th century and the early 20th century, walruses were widely hunted and killed for their blubber, walrus ivory, and meat. The population of walruses dropped rapidly all around the Arctic region. Their population has rebounded somewhat since then, though the populations of Atlantic and Laptev walruses remain fragmented and at low levels compared with the time before human interference.
The white-faced saki (Pithecia Pithecia), called the Guianan Saki and the golden-faced saki, is a species of the New World saki monkey. They can be found in Brazil, French Guiana, Guyana, Suriname, and Venezuela. This species lives in the understory and lower canopy of the forest, feeding mostly on fruits, nuts, seeds, and insects. Although they are arboreal creatures and are specialists of swinging from tree to tree (brachiation), they are also terrestrial when foraging. White-faced sakis typically live around 14 years in their natural habitat and have been recorded to live up to 36 years in captivity. Sakis are active in the day and sleep highly elevated (15-20m) in trees with many leaves to shelter them from weather and flying predators. [6]
The wildebeest (/ˈwɪldɪbiːst/ WIL-dib-eest,[1][2][3] /ˈvɪl-/ VIL-,[3] /-dəb-/, plural wildebeest or wildebeests), also called the gnu (/njuː/ NEW or /nuː/ NOO),[4][5][6] is an antelope in the genus Connochaetes. It belongs to the family Bovidae, which includes antelopes, cattle, goats, sheep, and other even-toed horned ungulates. Connochaetes includes two species, both native to Africa: the black wildebeest or white-tailed gnu (C. gnou), and the blue wildebeest or brindled gnu (C. taurinus).
Fossil records suggest these two species diverged about one million years ago, resulting in a northern and a southern species. The blue wildebeest remained in its original range and changed very little from the ancestral species, while the black wildebeest changed more like an adaptation to its open grassland habitat in the south. The most obvious way of telling the two species apart are the differences in their coloring and in the way their horns are oriented.[7]
In East Africa, the blue wildebeest is the most abundant big-game species; some populations perform an annual migration to new grazing grounds, but the black wildebeest is merely nomadic. Breeding in both takes place over a short period of time at the end of the rainy season and the calves are soon active and are able to move with the herd, a fact necessary for their survival. Nevertheless, some fall prey to large carnivores, especially the spotted hyena.
Wildebeest often graze in mixed herds with zebra, which gives heightened awareness of potential predators. They are also alert to the warning signals emitted by other animals such as baboons. Wildebeest are a tourist attraction but compete with domesticated livestock for pasture and are sometimes blamed by farmers for transferring diseases and parasites to their cattle. Some illegal hunting goes on but the population trend is fairly stable and some populations are in national parks or on private land. The International Union for Conservation of Nature lists both as least-concern species.
The wolf (Canis lupus[a]), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of Canis lupus have been recognized, and gray wolves, as colloquially understood, comprise non-domestic/feral subspecies. The wolf is the largest extant member of Canidae, males averaging 40 kg (88 lb) and females 37 kg (82 lb). Wolves measure 105–160 cm (41–63 in) in length and 80–85 cm (31–33 in) at shoulder height. The wolf is also distinguished from other Canis species by its less pointed ears and muzzle, as well as a shorter torso and a longer tail. The wolf is nonetheless related closely enough to smaller Canis species, such as the coyote and the golden jackal, to produce fertile hybrids with them. The banded fur of a wolf is usually mottled white, brown, gray, and black, although subspecies in the arctic region may be nearly all white.
Of all members of the genus Canis, the wolf is most specialized for cooperative game hunting as demonstrated by its physical adaptations to tackling large prey, its more social nature, and its highly advanced expressive behavior. It travels in nuclear families consisting of a mated pair accompanied by their offspring. Offspring may leave to form their own packs on the onset of sexual maturity and in response to competition for food within the pack. Wolves are also territorial and fights over territory are among the principal causes of wolf mortality. The wolf is mainly a carnivore and feeds on large wild hooved mammals as well as smaller animals, livestock, carrion, and garbage. Single wolves or mated pairs typically have higher success rates in hunting than do large packs. Pathogens and parasites, notably rabies virus, may infect wolves.
The global wild wolf population was estimated to be 300,000 in 2003 and is considered to be of Least Concern by the International Union for Conservation of Nature (IUCN). Wolves have a long history of interactions with humans, having been despised and hunted in most pastoral communities because of their attacks on livestock, while conversely being respected in some agrarian and hunter-gatherer societies. The wolf is also considered the ancestor of most domestic dog breeds. Although the fear of wolves exists in many human societies, the majority of recorded attacks on people have been attributed to animals suffering from rabies. Wolf attacks on humans are rare because wolves are relatively few, live away from people, and have developed a fear of humans because of their experiences with hunters, ranchers, and shepherds.
The Wolverine (/ˈwʊlvəriːn/) (also spelled wolverene), Gulo gulo (Gulo is Latin for "glutton"), also referred to as the glutton, carcajou, skunk bear, or quickhatch (from East Cree, kwiihkwahaacheew), is the largest land-dwelling species of the family Mustelidae. It is a stocky and muscular carnivore, more closely resembling a small bear than other mustelids. A solitary animal,[2] it has a reputation for ferocity and strength out of proportion to its size, with the documented ability to kill prey many times larger than itself.
The wolverine is found primarily in remote reaches of the Northern boreal forests and subarctic and alpine tundra of the Northern Hemisphere, with the greatest numbers in Northern Canada, the U.S. state of Alaska, the mainland Nordic countries of Europe, and throughout western Russia and Siberia. Its population has steadily declined since the 19th century owing to trapping, range reduction, and habitat fragmentation. The wolverine is now essentially absent from the southern end of its European range.
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