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  The Magnificent World of Snakes 

Snakes which have an important role to play in various potions of Chinese traditional medicine have often had a bad press in the West. To a large extent, this stems from the Christian Bible story about the snake in the Garden of Eden being the tempter and the cause of the downfall of Adam and Eve, the first man and woman in Biblical mythology. The legend goes that God said the snake would forever crawl on its belly as a result of its wrongdoing.

However, 20th_century scientists are interested not only in the snake’s powers of locomotion, but in its numerous characteristics. Snakes such as the extensive boa family of South America or the cobra family of south Asia have many unknown aspects. Scientists are still exploring and discussing the differences in the classification of these snakes, the range of their habitats and so on, all the while discovering new aspects of reptilian creatures.

One scientist feels that snakes are under-valued. Robert W.   Henderson has worked with the Bronx Zoo Wildlife Conservation Society of New York and the Venezuelan government in classifying the boa family n South America. He says there are gaping holes in the knowledge about the boa constrictor, tree boa, anaconda and other snakes of this family, and these animals “are every bit as splendid as tigers, whales, bald eagles or pandas”.

A quick rundown of some known facts about snakes gives an idea of the variety and character to be found among the different types:

The green anaconda is the most massive snake in the world. The female anaconda can weigh more than 910 kilograms. These South American snakes can grow up to more than eight metres long.

Snakes have hinged jaws which allow them to swallow large animals which are equivalent to a good proportion of their own body weight. However, because snakes cannot chew, they are gape-limited, that is, limited to prey which they can take in whole in one gape or swallow.

Anacondas have been recorded as eating whole, small deer. A36-kilogram anaconda was recorded as killing (by constricting its strong coils) and swallowing a 16-kilogram capybara, a large South American rodent, which was nearly half the snake’s body weight.

A female anaconda mates with as many as a dozen of the much smaller males. They form AA “breeding ball” in which the male snakes coil along the length of the female, and can remain together for several weeks. The female later fives birth to as many as 70 young snakes, most of which will be eaten by various predators.

Tree boas have deep. Heat-sensitive pits on the scales around their mouth. This sense allows snakes to target warmblooded prey in darkest conditions in dense jungle.

The pit viper family of snakes (including rattlesnakes and copperheads) has heat-sensing pits in the face, and nocturnal vision, a sense that helps to detect prey in the dark. Animals that hunt at night have proportionally bigger eyes then humans, and pupils that open more widely to gather more light than human eyes do in dark conditions.  Nocturnal snakes also have more rods in their eyes for low-light detecting, and a mirror-like membrane which reflects light through the retina a second time. This gives the low light another chance to stride the light-sensitive rods.

The most poisonous snake is the sea snake.  A single drop of its venom can kill a person.  Sea snakes feed on fish and crabs, and do not attack humans unprovoked, They can swim to a depth of 45 metres and stay under water for several hours before surfacing for breath.

The king cobra, the world’s longest poisonous snake which can reach five metres long, is unique among snakes in making a nest for its eggs. The female of the cobra, which is found in southern China, the Philippines, Malaysia and India, remains on the nest for three weeks until the eggs hatch.

When roused, the hood of the cobra is extended by ribs behind its head pushing out loose skin.

The spitting cobra of Africa can accurately project its venom more than two metres.

 Oriental snake charmers use the cobra because these snakes respond well to musical cues and look spectacular when their hoods are extended.

While snakes are seen as dangerous and aggressive for many animals, the aquatic and small land snakes of southern Asia have to be careful themselves of another aggressor-the fishing cat (Felis viverrinda). This stocky but heavy cat (which can weigh up to 12 kilograms) lives near swamps, marshes and reed beds. It may dive headfirst into the water to catch fish or cars, or tap the water with its paw to draw aquatic animals to where it waits on the bank. Other than fish, frogs, and crabs, the fishing cat also preys on land animals such as snakes, birds, and small mammals. When food is scarce, it may prey on dogs, goats, calves, and chicken. The fishing cat is generally a nocturnal hunter.

 

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