Scientists recently found three animal species living two miles below the surface of the Mediterra-nean Sea, where the super-salty waters don't have oxygen. They're multicellular (多细胞的),which means their bodies have many cells. They each are as small as a large grain of sand. But they are animals.
The most exciting thing about these creatures, say the scientists, is that they obviously don't need oxygen to live. What biologists know about life so far is that only single-celled living things can live in places that have no oxygen, and that multicellular organisms (有机物)can visit these places,but not live there. These newly found creatures could change that idea.
Finding animals down there was so surprising that the scientists couldn't believe it. “At first, we thought they were dead bodies, ” Roberto Danovaro ,a scientist at the Polytechnic University of Marche in Ancona, Italy, told Science News. To find out whether the animals could actually live there, Danovaro and his colleagues brought up more samples from the ocean floor. Studying the animals in the new samples showed that they appeared to be alive.
The researchers did more tests, and found that some of the animals had eggs—which suggests they were reproducing. Also in the samples were old skins, suggesting that the animals had lived there long enough to grow. Finally, pictures taken showed that the insides of the animals appear to adapt to living in an environment that has no oxygen.
These clues suggest the animals don't need oxy-gen, but the evidence is indirect, which means that scientists still have not observed how the animals live without oxygen. This means more studies are needed, but the scientists think they're on the right track. And if they're right, biologists will need to rethink what they know about where animals live.
What excited the scientists most is that __________.
A.they found three animal species visit the salty water under the Mediterranean Sea |
B.single-celled animals can live in super-salty waters |
C.the tiny animals have many cells |
D.three kinds of animals can live in places that have no oxygen |
The underlined phrase in Paragraph 2 means the scientists could think __________.
A.only single-celled creatures don't need oxygen to live |
B.multicellular animals can visit the super-salty waters |
C.the newly found creatures can't live in the super-salty waters |
D.multicellular animals can also live without oxy-gen besides single-celled ones |
Which of the following CAN'T be used to prove the newly found creatures can live in super-salty waters?
A.Their dead bodies are found there. |
B.Some in the samples have eggs. |
C.Some old skins are found in the samples. |
D.The pictures of their insides have been taken. |
More studies are needed to prove __________.
A.where single-celled animals can live |
B.how the newly found animals live without oxy-gen |
C.whether the multicellular creatures can live underwater |
D.why the super-salty waters have no oxygen |