Cats

Cat are also known as the Domestic Cat or House Cat to distinguish it from other felines, is a small carnivorous species of crepuscular mammal that is often valued by humans for its companionship and its ability to hunt vermin. It has been associated with humans for at least 9,500 years.

A skilled predator, the cat is known to hunt over 1,000 species for food. It is intelligent and can be trained to obey simple commands. Individual cats have also been known to learn to manipulate simple mechanisms, such as doorknobs. Cats use a variety of vocalizations and types of body language for communication, including mewing ("meow" or "miaow"), purring, hissing, growling, squeaking, chirping, clicking, and grunting. Cats are popular pets and are also bred and shown as registered pedigree pets. This hobby is known as the "Cat Fancy."

Cats typically weigh between 2.5 and 7 kg (5.5–16 pounds); however, some breeds, such as the Maine Coon, can exceed 11.3 kg (25 pounds). Some have been known to reach up to 23 kg (50 pounds) due to overfeeding.

Cats have 7 cervical vertebrae like almost all mammals, 13 thoracic vertebrae (humans have 12), 7 lumbar vertebrae (humans have 5), 3 sacral vertebrae like most mammals (humans have 5 because of their bipedal posture), and, except for Manx cats, 22 or 23 caudal vertebrae (humans have 3 to 5, fused into an internal coccyx). The extra lumbar and thoracic vertebrae account for the cat's enhanced spinal mobility and flexibility, compared with humans. The caudal vertebrae form the tail, used by the cat as a counterbalance to the body during quick movements. Cats also have free-floating clavicle bones, which allows them to pass their body through any space into which they can fit their head.

Cats have highly specialized teeth for the tearing of meat. The premolar and first molar together compose the carnassial pair on each side of the mouth, which efficiently functions to shear meat like a pair of scissors. While this is present in canids, it is highly developed in felines. The cat's tongue has sharp spines, or papillae, useful for retaining and ripping flesh from a carcass. These papillae are small backward-facing hooks that contain keratin which also assist in their grooming.

Thirty-two individual muscles in each ear allow for a manner of directional hearing. A cat can move each ear independently of the other. Because of this mobility, a cat can move its body in one direction and point its ears in another direction. Most cats have straight ears pointing upward.

Hippo

The hippopotamus (Hippopotamus amphibius), from the Greek ‘ιπποπόταμος (hippopotamos, hippos meaning "horse" and potamos meaning "river"), often shortened to "hippo", is a large, mostly plant-eating African mammal, one of only two extant species in the family Hippopotamidae (the other being the Pygmy Hippopotamus).

The hippopotamus is semi-aquatic, inhabiting rivers and lakes in sub-Saharan Africa in large groups of up to 40 hippos. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water, where territorial bulls preside over a stretch of river. They emerge at dusk to graze on grass. While hippos rest near each other in territories in the water, grazing is a solitary activity and hippos are not territorial on land.

Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans—whales, porpoises and the like. The common ancestor of whales and hippos split from other even-toed ungulates around 60 mya. The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 mya.

The hippopotamus is recognizable for its barrel-shaped torso, hairless body, stubby legs and tremendous size. It is similar in size to the White Rhinoceros; only elephants are consistently larger and despite its stocky shape and short legs, it can easily outrun a human. Despite its popularity in zoos and cuddly portrayal as gentle giants in fiction, the hippopotamus is among the most dangerous and aggressive of all mammals. There are an estimated 125,000 to 150,000 hippos remaining throughout Sub-Saharan Africa, of which Zambia (40,000) and Tanzania (20,000-30,000) have the largest populations. They are still threatened by poaching for their meat and ivory canine teeth, and by habitat loss.

Lion

The lion (Panthera leo) is a member of the family Felidae and one of four "big cats" in the genus Panthera. Reaching 272 kg (600 lb), it is the second-largest cat after the tiger. They currently exist in the wild in sub-Saharan Africa and in Asia with a critically endangered remnant population in northwest India, having disappeared from North Africa, the Middle East and western Asia in historic times. Until the late Pleistocene (about 10,000 years ago), the lion was the most widespread large land mammal beside man. They were found in most of Africa, much of Eurasia from western Europe to India and the Bering land bridge and in the Americas from Yukon to Peru.

Lions live for approximately 10–14 years in the wild, while in captivity they can live over 20 years. They typically inhabit savanna and grassland, although they may take to bush and forest. Lions are unusually social compared to other cats. A lion pride consists of related females and offspring and a small number of dominant males. Groups of female lions typically hunt together, preying mostly on large ungulates. The lion is an apex and keystone predator, though will resort to scavenging if the opportunity arises. While lions, in general, do not selectively hunt humans, some have been known to become man-eaters and seek human prey.

The lion is a vulnerable species, having seen a possibly irreversible population decline of 30 to 50% over the past two decades in its African range;^[1] populations are untenable outside designated reserves and national parks. Although the cause of the decline is not well-understood, habitat loss and conflicts with humans are currently the greatest causes of concern. Lions have been kept in menageries since Roman times and have been a key species sought after and exhibited in zoos the world over since the late 18th century. Zoos are cooperating worldwide in breeding programs for the endangered Asiatic subspecies.

The male lion is highly distinctive and is easily recognized by its mane. The lion, particularly the face of the male, is one of the most widely recognized animal symbols in human culture. Depictions have existed from the Upper Paleolithic period, with carvings and paintings from the Lascaux and Chauvet Caves, through virtually all ancient and medieval cultures where they historically occurred. It has been extensively depicted in literature, in sculptures, in paintings, on national flags, and in contemporary films and literature.

Zebra

The Zebra is an odd-toed ungulate of the Equidae family; native to eastern, southern and southwestern Africa. It is best known for its distinctive white and black stripes, which come in different patterns unique to each individual. They are generally social animals and can be seen in large herds with other grazers.

In addition to their stripes, zebras have erect, mohawk-like manes. They are generally 2.3 m (8ft) long, stand 1.25-1.5 m (4-5ft) at the shoulder, and weigh around 300kg (660 lbs), although some can grow to more than 410 kg (900 lbs). Unlike their closest relatives, horses and donkeys, zebras have not been truly domesticated. There are three species of zebra: the Plains Zebra, Grevy's Zebra and the Mountain Zebra. They can be found in a variety of habitats, such as grasslands, savannas, woodlands, thorny scrublands, mountains and coastal hills.

The pronunciation is IPA: /ˈzɛbrə/ (ZEB-ra) in the United Kingdom and /ˈziːbrə/ (ZEE-bra) in North America.

Elephant

The elephants (Elephantidae) are a family in the order Proboscidea in the class Mammalia. They were once classified along with other thick skinned animals in a now invalid order, Pachydermata. There are three living species: the African Bush Elephant, the African Forest Elephant (until recently known collectively as the African Elephant), and the Asian Elephant (also known as the Indian Elephant). Other species have become extinct since the last ice age, which ended about 10,000 years ago, the Mammoth being the most well-known of these.

The word "elephant" has its origins in the Greek ἐλέφας, meaning "ivory" or "elephant".

Elephants are mammals, and the largest land animals alive today. The elephant's gestation period is 22 months, the longest of any land animal. At birth it is common for an elephant calf to weigh 120 kilograms (265 lb). An elephant may live as long as 70 years, sometimes longer. The largest elephant ever recorded was shot in Angola in 1956. This male weighed about 12,000 kg (26,400 lb), with a shoulder height of 4.2 m (13.8 ft), a metre (3 ft 4 in) taller than the average male African elephant. The smallest elephants, about the size of a calf or a large pig, were a prehistoric species that lived on the island of Crete during the Pleistocene epoch.

Elephants are symbols of wisdom in Asian cultures, and are famed for their memory and high intelligence, and are thought to be on par with cetaceans and hominids. Aristotle once said the elephant was "the beast which passeth all others in wit and mind."

Bear

Bears (family Ursidae) are large mammals in the order Carnivora. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although there are only eight living species of bear, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere.

Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, plantigrade paws with five nonretractile claws, and a short tail. While the polar bear is mostly carnivorous and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous, with largely varied diets including both plants and animals.

With the exceptions of courting individuals and mothers with their young, bears are typically solitary animals. They are sometimes diurnal, but are usually active during the night (nocturnal) or twilight (crepuscular). Bears are aided by an excellent sense of smell, and despite their heavy build and awkward gait, they can run quickly and are adept climbers and swimmers. Bears use shelters such as caves and burrows as their dens, which are occupied by most species during the winter for a long period of sleep similar to hibernation.

Deer

A deer is a ruminant mammal belonging to the family Cervidae. A number of broadly similar animals from related families within the order Artiodactyla (even-toed ungulates) are often also called deer. Male deer, also called bucks, grow and shed new antlers each year, as opposed to antelope, which are in the same order and bear a superficial resemblance to deer physically, but are permanently-horned. Deer tend to travel in herds of nine and gather in low elevations.