Dolphins appear to make a tasty meal for many predators (捕食性动物). And why? With an exceptionally high fat content, dolphins provide great nutrition for predators who track throughout the ocean. However, dolphins are more troublesome than it’s worth and most predators generally learn to avoid dolphin groups, including sharks. Like elephants, dolphins will circle protectively around the weak members of the group, and attack anything that approaches in a threatening manner. And they can kill sharks. Most predators take one look, and then just swim away.
Dolphins don’t worry a lot about being eaten. In general, their only real predator is the shark, and even then only the larger species of sharks dare to attack dolphins. Dolphins have evolved (进化) over a long time to be pretty tough, so in general even the most dangerous sharks stay away from them. Dolphin parts have been found in the bellies of killer whales, who will eat just about anything. In fact, dolphins and killer whales team up sometimes to catch some prey.
As with most edible (可以食用的) species today, the most dangerous threat is man. Sometimes, dolphins are killed not because they are a source of food, but because they prey on the same fish species as humans. Therefore, many fishermen have killed dolphins specifically because they think dolphins will ruin their catch.
Even more, there are some countries that eat cetaceans, including dolphins. In Japan, the meat of some dolphin species is seen as a delicacy, and can cost up to $25 a pound. In Peru and many other Latin American countries where the ocean has been largely short of fish due to overfishing or environmental conditions such as El Niño, fishermen have turned to catch dolphins and porpoises to sell in fish markets.
5. What can we learn from the first paragraph?
A.No ocean animals can attack dolphins. | B.Dolphins are not easy to deal with. |
C.Dolphins often kill sharks. | D.Dolphins are quite low in fat. |
6. What does the underlined part in the passage mean?
A.People have ever found the evidence of killer whales eating dolphins. |
B.Dolphins and killer whales have something in common concerning bellies. |
C.Dolphins and killer whales join hands to hunt and feed. |
D.Dolphins and killer whales are not similar in belly parts. |
7. Which is one of the reasons why dolphins are killed according to Para. 3?
A.The number of dolphins is too large. |
B.Dolphins are more delicious than other species. |
C.Dolphins compete with humans on the same fish species. |
D.Dolphins’ meat is the main economic source for some fishermen. |
8. Why do the Japanese kill dolphins?
A.Dolphins cause overfishing. |
B.Dolphins affect their way of living. |
C.Dolphins are a source of delicious food. |
D.There are not so many fish in the ocean as before. |