Deer are generally slender and long-legged. Their most striking characteristic is the presence of antlers. The deer family includes about 45 species. The legs are long and slender, well-suited for fast running. Most species of deer have antlers. Usually only males have them, however, in Rangifer, the caribou, both sexes have antlers. Other species, such as the Chinese water deer and the tufted deer, have tusks. Deer are native to Europe, Asia, North America, South America, and northern Africa. People have brought them to Australia, New Zealand, and other areas. Most deer live in small family groups, though the males generally spend some time alone. Female deer usually give birth to one or two young.
The smallest deer, the South American pudu, is about 30 centimeters tall at the shoulder. The largest deer, the moose, may be more than 2.1 meters tall at the shoulder.
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Gulls are among the most common waterbirds of ocean and coastal zones worldwide. There are more than 40 species of gull, including kittiwakes. Adult gulls are usually white or gray, sometimes with dark markings. They range in length from about 28 to 79 centimeters. A gull’s bill is strong and slightly hooked. Their wings are long and pointed, and gulls have a short squared tail.
Along the shore, gulls are helpful to the people who clean beaches and harbors. They swoop down to pick up messy things. Gulls eat almost anything, from dead fish and animals to potato chips. Gulls also follow fishing boats, feeding on offal and by-catch as it is discarded overboard. These birds eat all day long just to stay alive. While flying many miles without stopping, they use up a lot of energy. Some gulls travel enormous distances between their summer and winter homes.
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Crayfish are freshwater crustaceans of the order Decapoda, which includes crabs, shrimps, lobsters, and hermit crabs. Crayfish are found on all continents on Earth except Africa and Antarctica. They are an essential part of the food chain. They feed on algae, insects, mussels, and snails, while fish, herons, otters, and other larger animals feed on them. This feeding balance has been maintained for hundreds of thousands of years. Unfortunately, people destroy this balance.
Crayfish evolved from marine ancestors dating back some 280 million years. There are more than 300 species of crayfish worldwide. Although nearly half of the species are endangered or imperiled. They live in water, hiding beneath rocks, logs, sand, mud, and vegetation. Some species dig burrows.
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Only the female mosquito bites and leaves those itchy lumps on our arms and legs. She needs the blood for her eggs to develop. The humming sound we hear comes from the fast beat of the mosquito’s wings. The male mosquito feeds on nectar and other plant juices. Mosquitoes are part of a large group of insects called flies. A mosquito has two narrow wings, two antennas, and six long legs. A female mosquito usually has a mouthpart called a proboscis, which looks like a long tube. There are more than 3000 species of mosquitoes.
Mosquitoes are usually found wherever the weather is damp or where there are rivers, lakes, or swamps. That’s because these insects must lay their eggs in water. They even lay eggs in tin cans partly filled with rainwater. Mosquitoes have four stages in their life cycle beginning with the egg, then proceeding into a larva stage, followed by a pupa stage, and finally adulthood. When the eggs hatch, the young mosquitoes look like little worms.
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Cod is an important sources of food. Cod-liver oil is very rich in vitamins A and D and other things that people need to stay healthy. There are about 21 genera and 55 species of codfishes.
Cod live in the cold waters of the northern Atlantic and Pacific oceans, and the North Sea in Europe. They are gray-green fish with speckles and a white line on their sides. Atlantic cod may also be reddish in color. Pacific cod is smaller than their Atlantic relatives.
Barbel, a thin tentacle that hangs from the cod’s lower jaw, is an unusual physical feature of the cod. Scientists think this organ may be a tool for finding food.
In fact, cod may grow to be 1.8 meters long and more than 90 kilograms in weight.
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The bullfinch has a bright red breast and gray back set off by a coal–black head. However, only males have red breasts, the female’s breasts are brown. They have an excellent ability to imitate different sounds. Some of these birds can memorize and whistle several very complex melodies. All you need is patience to train a bird. It is quite easy to tame bullfinch.
Despite the fact that most bullfinches live in Eurasia, the largest of them, white-cheeked bullfinches, live in the hot Philippines.
In captivity, these birds live less than in nature. The weight of an adult bullfinch is about thirty grams.
Bullfinches are monogamous. During the breeding season, males coax females by offering food. Males never take part in the construction of a nest. Nestlings of bullfinches gain their independence in the third week of life.
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Flies belong to a group that also includes mosquitoes, gnats, and midges. There are about 100,000 species of fly. They live in almost every corner of the globe – in soils, plants, and around water bodies. Many flies are free-living, feeding off a wide range of plants, while others are parasites and scavengers. A number are of economic importance in controlling pest species, while others serve as vectors for a range of human, animal, and plant diseases.
Flies have a single pair of functional wings and a pair of knoblike vestigial wings known as halteres. Its head is free-moving and attached by a slender neck to the thorax. The fly has two large compound eyes. It has three pairs of legs, each ending in a pair of claws. Crane flies are exceptional in having extremely long legs.
Many species are a dull dung color. Hover flies are among the most colorful species, many of which are colored in similar patterns to bees and wasps.
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