American Bullfrog

The American Bullfrog (Rana catesbeiana) is an aquatic frog, a member of the family Ranidae, or "true frogs", native to much of North America. This is a frog of larger, permanent water bodies, swamps, ponds, lakes, where it is usually found along the water's edge . On rainy nights, bullfrogs along with many other amphibians, go overland and may be seen in numbers on country roads.

American bullfrogs live longer in warm weather. They have been widely introduced across North America (see range map). The original, naturally determined range did not include far western regions where it is found today.

Western tiger swallowtail

The Western tiger swallowtail (Papilio rutulus) is a common swallowtail butterfly of western North America, frequently seen in urban parks and gardens as well as in rural woodlands and riperian areas. It is a large, brightly colored and active butterfly, rarely seen at rest; its wingspan is 7 to 10 cm, and its wings are yellow with black stripes, and in addition it has blue and orange spots near its tail. It has the "tails" on the hind wings that are often found in swallowtails.

Polar bear

The polar bear (Ursus maritimus) is a bear native largely within the Arctic circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the world's largest carnivore species found on land. It is also the largest bear, together with the omnivore Kodiak bear which is approximately the same size. An adult male weighs around 400–680 kg (880–1,500 lb), while an adult female is about half that size. Although it is closely related to the brown bear, it has evolved to occupy a narrow ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the seals which make up most of its diet. Although most polar bears are born on land, it spends most of its time at sea, hence its name meaning "maritime bear", and can hunt consistently only from sea ice, spending much of the year on the frozen sea.

The polar bear is classified as a vulnerable species, with 5 of the 19 polar bear subpopulations in decline. For decades, unrestricted hunting raised international concern for the future of the species; populations have rebounded after controls and quotas began to take effect. For thousands of years, the polar bear has been a key figure in the material, spiritual, and cultural life of Arctic indigenous peoples, and the hunting of polar bears remains important in their cultures.

The IUCN now lists global warming as the most significant threat to the polar bear, primarily because the melting of its sea ice habitat reduces its ability to find sufficient food. The IUCN states, "If climatic trends continue polar bears may become extirpated from most of their range within 100 years."On May 14, 2008, the United States Department of the Interior listed the polar bear as a threatened species under the Endangered Species Act.

Zebu

Zebu, Bos primigenius indicus or Bos indicus, sometimes known as humped cattle or indicus cattle, are a type of domestic cattle originating in South Asia. They are characterised by a fatty hump on their shoulders, drooping ears and a large dewlap. They are highly adapted to high temperatures, and are farmed throughout the tropical countries, both as pure zebu and as hybirds with taurine cattle, the other main type of domestic cattle. Zebu are used as draught oxen, as dairy cattle and as beef cattle, as well as for byproducts such as hides and dung for fuel and manure.

Zebras

Zebras are African equids best known for their distinctive white and black stripes. Their stripes come in different patterns unique to each individual. They are generally social animals and can be seen in small harems to large herds. In addition to their stripes, zebras have erect, mohawk-like manes. Unlike their closest relatives, horses and asses, zebras have never been truly domesticated.

There are three species of zebra: the Plains Zebra, Grevy's Zebra and the Mountain Zebra. The Plains zebra and the Mountain Zebra belong to the subgenus Hippotigris, but Grevy's zebra is the sole species of subgenus Dolichohippus. The latter resembles an ass while the former two are more horse-like. Nevertheless, DNA and molecular data show that zebras do indeed have monophyletic origins. All three belong to the genus Equus along with other living equids. In certain regions of Kenya, Plains zebras and Grevy's zebras coexist.

The unique stripes and behaviors of zebras make these among the animals most familiar to people. They can be found in a variety of habitats, such as grasslands, savannas, woodlands, thorny scrublands, mountains and coastal hills. However, various anthropogenic factors have severely impacted zebra populations, in particular hunting for skins and habitat destruction. Grevy's zebra and the Mountain zebra are endangered. While Plains zebras are much more plentiful, one subspecies, the quagga, went extinct in the late nineteenth century.

The name "zebra" comes from the Old Portuguese word zevra which means "wild ass". The pronunciation is /'zebra/ ZEB-ra internationally, or /'zi:bra/ ZEE-bra in North America.

yak

The yak (Bos grunniens) (Tubetan: གཡག་; Wylie: g.yak) is a long-haired bovine found throughout the Himalayan region of south Central Asia, the Tibetan Plateau and as far north as Mongolia. In addition to a large domestic population, there is a small, vulnerable wild yak population. In Tibetan, the word gyag refers only to the male of the species; a female is a dri or nak. In most languages which borrowed the word, including English, yak is usually used for both sexes.

Yaks belong to the genus Bos, and are, therefore, closely related to cattle, with whom they commonly interbreed, as well as the Southeast Asian banteng, gaur or Indian Bison, and the now extremely rare Kouprey.

Yaks are herd animals. Wild male yaks stand about 2 to 2.2 metres (6.6 to 7.2 ft) tall at the shoulder and average 1,000 kg (2,200 lb); the females weigh about one third of this. domesticated yaks are much smaller, males weighing 350 to 580 kg (770 to 1,300 lb) and females 225 to 255 kg (500 to 560 lb). Both types have long shaggy hair to insulate them from the cold. Wild yaks can be brown or black. Domesticated ones can also be white. Both males and females have horns.

Domestic yaks mate in about September; the females may first conceive at about 3–4 years of age, calving April to June about every other or every third year, apparently depending upon food supply. This gestation period is approximately 9 months. In the absence of more data, wild animals are assumed to mirror this reproductive behavior. Calves will be weaned at one year and become independent shortly thereafter. Yaks may live to somewhat more than 20 years.

worm

The term worm is used to describe many different distantly-related animals which have a long cylindrical body and no legs.

Most animals called "worms" are invertebrates, but the term is also used for the amphbian caecilians and the slow worm Anguis, a legless burrowing lizard. Invertebrate animals commonly called "worms" include annelids (earthworms), nematodes (roundworms), flatworms, marine polychaete worms (bristle worms), marine nemertean worm ("bootlace worms"), and insect larvae such as caterpillars, grubs, and maggots.

Worms vary in size from microscopic to over a metre in length for marine polychaete worms (bristle worms), 6.7 m (22 ft) for the African giant earthworm, Microchaetus rappi, and 55 m (180 ft) for the marine nemertean worm (bootlace worm), Lineus longissimus.

Historical English-speaking cultures have used the (now depreciated) terms worm, wurm, or wyrm to describe carnivorous reptiles ("serpents"), and the related mythical beasts dragons.

Various types of worm occupy a wide variety of parasitic niches, living inside the bodies of other animals. Free-living worm species may live on land, in marine or freshwater environments, or burrow.