1. Koala
Length: 60-85 centimeters
Life span: 10-15 years
Physical Description:
The Koala has large, sharp claws to assist with climbing tree trunks. The koala's five fingers are arranged with opposable thumbs, providing better gripping ability. The first two fingers are positioned in apposition on the front paws, and the first three fingers for the hind paws. The teeth of koalas are adapted to their herbivorous diet, and are similar to those of other diprotodont marsupials, such as kangaroos and wombats. They have sharp incisors to clip leaves at the front of the mouth, separated from the grinding cheek teeth by a wide diastema.
Reproduction:
Females reach maturity at 2 to 3 years of age, males at 3 to 4 years. If healthy, a female Koala can produce one young each year for about 12 years. Gestation is 35 days. Mating normally occurs between December and March, the Southern Hemisphere's summer.
A baby koala is referred to as a joey and is hairless, blind, and earless when born. Young remain hidden in the pouch for about six months, only feeding on milk. During this time they grow ears, eyes, and fur. The joey then begins to explore outside of the pouch. The baby koala will remain with the mother for another six months or so, riding on her back, and feeding on both milk and eucalyptus leaves until weaning is complete at about 12 months of age. Young females disperse to nearby areas at that time; young males often stay in the mother's home range until they are two or three years old.
Diet:
Koalas only eat eucalyptus leaves. Koalas prefer the leaves of about three dozen varieties. Joeys learn to eat eucalyptus leaves on their own gradually. At first the joey goes after leaves with its mouth. Its early attempts look like a game of bobbing for apples, with its nose getting in the way and pushing the leaves out of reach! Fortunately, joeys keep trying until they are successful. Eventually they figure out how to grab leaves with their front paws and put them in their mouths.
2. Otter
Length: 6 feet
Characteristics:
Otter fur is a rich dark brown, lighter on the underparts; the throat and chin are grayish, the nose black and bare. Two fur layers -- short dense underfur and longer guard hairs -- combine with a subcutaneous layer of fat to insulate the body. In autumn, the normally thick fur grows in even thicker for extra cold resistance. All four feet are wide and webbed between the toes, although the hind pair are used more in swimming than the front pair.
Diet:
Otters obtain most of their food from the water. They love to eat fish such as minnows, sunfish, suckers, carp and trout. Other foods are frogs, turtles, snails, mussels, crayfish, snakes and snake eggs, worms, insects, aquatic plants, roots and, occasionally, muskrats.
Reproduction:
Otters mature sexually by two years of age. They breed sometime between January and May, mating taking place in the water. Approximately two months later, from February to April, one to five (most often two or three) young are born. Females usually have their first litter at age three. Baby otters are referred to as pups and weigh 4-5 ounces and are blind and toothless at birth. They do not open their eyes for five weeks, and their mother keeps them in the den until they are three or four months old.
Habitat:
Otters are found in extremely varied habitat in North America, including high Rocky Mountain lakes, spruce and birch forests in the North, marshes and swamps in the South, and major river basins. Dens may be excavations under tree roots or rock piles, abandoned beaver, muskrat or woodchuck burrows, or unused beaver lodges. A typical den has an underwater entrance hole, a living space above water level and several air or exit-entry holes to dry ground.
3. Rabbits
Length: 30-60 centimetres
Life span: 5-10 years
Characteristics and anatomy:
The long ears of rabbits are most likely an adaptation for detecting predators. In addition to their prominent ears, which can measure up to 6 cm (more than 2 inches) long, rabbits have long, powerful hind legs and a short tail. Each foot has five digits (one reduced); rabbits move about on the tips of the digits in a fashion known as digitigrade locomotion. Full-bodied and egg-shaped, wild rabbits are rather uniform in body proportions and stance.
Diet:
Rabbits are herbivores who feed by grazing on grass, forbs, and leafy weeds. In addition, their diet contains large amounts of cellulose, which is hard to digest. Rabbits solve this problem by passing two distinctive types of feces: hard droppings and soft black viscous pellets, the latter of which are immediately eaten. Rabbits reingest their own droppings in order to fully digest their food and extract sufficient nutrients.
Reproduction:
Most rabbits produce many offspring each year, although scarcity of resources may cause this potential to be suppressed. A combination of factors allows the high rates of reproduction commonly associated with rabbits. Rabbits generally are able to breed at a young age, and many regularly conceive litters of up to seven young, often doing so four or five times a year due to the fact that a rabbit's gestation period is only 28 to 31 days. Newborn rabbits are naked, blind, and helpless at birth. The young grow rapidly, and most are weaned in about a month.
Location and Habitats:
Rabbits are ground dwellers that live in environments ranging from desert to tropical forest and wetland. Their natural geographic range encompasses the middle latitudes of the Western Hemisphere. In the Eastern Hemisphere rabbits are found in Europe, portions of Central and Southern Africa, the Indian subcontinent, Sumatra, and Japan. The European rabbit has been introduced to many locations around the world, and all breeds of domestic rabbit originate from the European. Nearly half of the world's rabbit species are in danger of extinction; many are among the most vulnerable of all mammals.
4. Kangaroo
Length: 20-25 feet
Different species of kangaroos eat different diets. Eastern grey kangaroos are predominantly grazers eating a wide variety of grasses whereas some other species (e.g. red kangaroos and swamp wallabies) include significant amounts of shrubs in the diet. The smaller species of kangaroos also consume hypogeal fungi. Many species are nocturnal and crepuscular, usually spending the days resting in shade and the cool evenings, nights and mornings moving about and feeding.
Reproduction:
As with all marsupials, the young are born at a very early stage of development – after a gestation of 31–36 days. The joey will usually stay in the pouch for about nine months before starting to leave the pouch for small periods of time. It is usually fed by its mother until reaching 18 months. The female kangaroo is usually pregnant in permanence, except on the day she gives birth; however, she has the ability to freeze the development of an embryo until the previous joey is able to leave the pouch. This is known as diapause, and will occur in times of drought and in areas with poor food sources. The composition of the milk produced by the mother varies according to the needs of the joey. In addition, the mother is able to produce two different kinds of milk simultaneously for the newborn and the older joey still in the pouch.
Species of Kangaroos:
~The Red Kangaroo
~The Eastern Grey Kangaroo
~The Western Grey Kangaroo
~The Antilopine Kangaroo
5. Owls
Length: 5-28 inches
Characteristics:
Owls have large forward-facing eyes and ears, a hawk-like beak, and usually a conspicuous circle of feathers around each eye called a facial disc. Although owls have binocular vision, their large eyes are fixed in their sockets, as with other birds, and they must turn their entire head to change views.
Outer Covering:
The owls outer covering is feathers. Another important adaptation for owls is silent flight. Where other birds have stiff feathers that make a whooshing sound when they fly, owl feathers have soft edges that allow them to fly silently. This is important for owls, allowing them to swoop down on prey without being heard. In the darkness, owls don’t soar like eagles or hawks but rather fly low to the ground as they look for prey, from small rodents to fish. Larger owls have been known to carry off young deer, weasels, and foxes.
Family Life:
Male owls may bring offerings of food, dropping the item near the female to catch her interest. Even so, it may be several hours before she loses her fear and moves closer to him. The number of eggs that are laid depends on the food supply. If prey is scarce, only two or three eggs may be laid; if food is easily available, then six or more eggs may be laid. Chicks generally hatch two days apart, with the oldest chicks getting the most food. This ensures survival of at least a few chicks if food is scarce.Young owl chicks get the best of care from their mother for about three months. They are fed, protected from predators, and learn to fly and hunt so they can leave the nest and find territories of their own. Fathers are also often involved in rearing the chicks, including sitting on the eggs and bringing food back for the family. By about six months, most owl chicks look like their parents.
No comments:
Post a Comment