人教版高三英语课文全册Unit 14 Zoology - Reading 2
EAT OR BE EATEN (Ⅰ)
All animals are part of the food chain: they are listed on someone else's menu and always run the risk of ending up as someone else's lunch, dinner or snack. To protect themselves from being eaten and to survive in the wild, many animals have developed clever ways to escape from or avoid danger.
Like human beings, animals often try to hide or run away when they are being attacked. Many animals have adapted to their environment in such a way that they can hide better. Having the right colour can make a big difference. Many animals have the same or similar colour as their environment, making it more difficult for other animals to find them. Some can change colour very quickly, even in a few seconds. Other animals and insects have a body shape that helps them hide. Some insects look just like a small stick and can easily hide in a tree or bush.
If it is too late to hide or run away, an animal must use other methods to survive an attack. One type of snake that lives in Texas has developed an interesting way to defend itself. If it is attacked, it first makes itself look bigger and pretends to be a dangerous snake. If that doesn't work, the snake uses another trick: it rolls over, opens its mouth and acts as if it were dead. The snake is such a good actor that it seems quite dead. If someone picks it up, it hangs like a rope and doesn't move. However, if you roll it back on its stomach, it will roll over on its back again in order to look dead.
Another way to survive an attack is to have useful body parts. The turtle has a thick shell that protects it from its enemies, and other animals have teeth, claws, and horns that they can use to defend themselves. There are also animals that can use their tails to fight off attackers. A long tail can be used to hit an attacker, and there is even an animal whose tail will break off so that it can run away if someone grabs it.
The best way to stay safe is to develop a way to receive an early warning when danger approaches. Many animals stay together in large groups and use sounds and body language to warn each other if they see or hear something suspicious. Some animals even work together with other species to stay safe. The birds you often see on the back of a water buffalo have an important job: they help warn the buffalo of danger.
EAT OR BE EATEN (Ⅱ)
The "eat or be eaten" nature of life in the wild also causes predators, or animals that hunt other animals, to adapt in order to become better at finding and killing their prey. Predators often use one of three basic strategies: they run after their prey, slowly follow their prey, or hide and wait for their prey. All three methods have their advantages and disadvantages. Running after the prey is usually effective, but it requires great speed and a lot of energy. Since the running makes the predator very tired, it usually selects large animals as its prey. By doing so, the difficult chase will be worth the effort. To slowly follow another animal, for example, to walk in the water looking for fish as many birds do, requires very little energy but takes a lot of time. A predator that hunts in this way can choose smaller prey, since the method is less firing and it can hunt several times a day. Hiding and waiting is of course the easiest way to hunt, but it is not as effective. It may take a very long time until something edible walks by. Therefore, animals that hunt in this way have adapted by digesting food slowly. They are able to go without food for a long period of time.
Scientists who study animals can often tell what an animal eats and how it hunts by looking at its body or bones. As the animals adapt, their bodies gradually change. The shape of an animal's head and other features provide clues to how and where the animal lives. There are still many questions, however, and the scientists can't explain some of the shapes and changes that they have found. For a long time, animal experts were puzzled by the fact that so many ancient reptiles had very long necks. A new archeological find in China may help scientists answer the question. Scientists found the bones of an ancient reptile that lived in Southeast China more than 230 million years ago. It looked a bit like a dinosaur, and it had a very long neck. The neck was about 1.7 metres long, twice as long as the creature's body, and the head was very small. Scientists now believe that the reptile used its long neck to hunt other animals. The neck made it possible for the reptile to hide in the depths of brown water and fool fish and other animals. An animal that saw the head "floating" on the surface would mistake it for a small harmless animal. When the prey got close enough to realise that the "animal" was in fact only the head of a large and dangerous creature, it would be too late. The ancient reptile could also change the shape of its neck in order to strike quickly and swallow its prey.
