It is like a scene from a horror film:a spider web is several meters wide,which is home to thousands of spiders.And that was what Jason G.Goldman,an animal behavior researcher,found along a muddy path in the Peruvian Amazon jungle—the web arched from tree to tree,a structure containing too many spiders to count.They appeared to function as a society,just like ants or bees.

Anelosimus eximius,the species Goldman met in the rainforest,is not the only kind of social spiders in the world,but it does construct the biggest webs.Some can reach more than 7.6m long and 1.5m wide.A web of that size could contain as many as 50,000 individual spiders.

Anelosimus eximius was first discovered more than a century ago by a French scientist named Eugene Simon.More social spiders have been discovered since.One was found as recently as 2006.

An Anelosimus eximius colony(群体) contains adult males and females as well as youngsters,but the majority of spiders on the web are females. Males account for only between 5% and 22% of any colony’s population.Social spiders work together to build,maintain and clean their webs.They work together to catch prey(猎物),and dine together when they trap a large feast.The females work together to care for the young in the colony.They feed their youngsters by vomiting(吐出) up food for them,just like mother birds.

Why did these spiders become social?Researchers have discovered three ecological(生态的) elements that often lead to cooperative(合作的) living among spiders.

Social spiders tend to feed on bigger prey,for one thing.Spiders living in places where it is difficult to hunt large or more profitable prey alone may eventually figure out that it is in their interest to work together.

1.What can we know about Anelosimus eximius from the text?

A. Its latest branch was found in 2006.

B. It was discovered by Jason G.Goldman.

C. It has been in existence for less than a century.

D. It builds bigger webs than other kinds of spiders.

2.Which of the following correctly shows the parts of an Anelosimus eximius colony?

A. B.

C. D.

3.What’s the main feature of social spiders?

A. They live on big prey.

B. They care for the young.

C. They live and work together.

D. They mainly exist in the rainforest.

4.The following paragraph would discuss .

A. new threats to spiders’ colonies

B. new research on spiders’ colonies

C. more reasons for spiders’ cooperative living

D. more species of social spiders in the world

Science, as we think, was born when the Greek(希腊) philosopher ( 哲学家 ) Thales ( about 640-546 B.C.) asked a difficult question: What makes up our universe?

No one had a ready answer, so Thales went on studying the earth around him, the sky and the stars. He saw so much water on earth and so much water falling from the sky as rain that he decided water must be the basic substance ( 物质 ) of the universe.

Other Greek thinkers became interested in this question. They suggested other answers. One said that because air lies around the earth, it must be air that makes up all things. Another said that fire, appearing in different forms, was the building block of the universe.

The Greek philosophers were feeling their way towards the ideas on which chemistry is based. Centuries later, scientists proved that the universe is made up of certain basic substances. But the list is much more complicated than the Greeks realized. We now know of 103 basic substances which we call “ elements ( 元素 )”.

1.Thales, the famous Greek philosopher, died when he was about _______________.

A. 94 years old B. 106years old

C. 40 years old D. 46 years old

2.The meaning of the underlined word “ complicated” in the last paragraph is “ ____________”.

A. not difficult B. not simple

C. not famous D. not different

3.On the whole, the passage tells about ______________.

A. early tries to understand the universe B. the famous Greek thinkers

C. water falling from the sky D. air lying all around the earth

4.After reading the passage, we can be sure that________________.

A. nothing ever changes in the universe

B. Thales decided that the basic substance of the universe was air

C. the universe is made up of four different substances

D. the early Greek thinkers did much valuable work for the progress of science

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