1 . GPS has completely transformed how we get around. But other animals have long had their navigation (领航) systems built right in.

“We know their eyes are quite sensitive to polarized (偏振的) light and the sky has a particular pattern of polarized light relative to the position of the sun,” Barbara Webb, a researcher at the University of Edinburgh, says.

You can see polarized light firsthand if you take a pair of polarized sunglasses and spin them against the sky-the light passing through the glasses changes. Webb says the insects have polarization like that built into their many eyes. “You can think of it as having lots of sunglasses pointing in different directions.”

But Webb was curious whether there’s really enough information in the sky to give insects an accurate sense of direction. So her team built a sensor (传感器) modeled after a desert ant eye and put it under artificial light meant to simulate the sky. They then put that sensor into a model meant to model the brains of desert ants and other insects. And they found that with the insects’ sensing and processing equipment, they can likely sense direction down to just a couple degrees of error.

A system based on that of insects could someday be a cheap, low-energy choice to GPS. Insects have very tiny brains. A brain the size of a pinhead that’s using hardly any energy. And yet they’re still able to navigate better than we can with GPS, which is surprising. Webb is now working on building a robot that can use light to get its directions.

1. What can we learn from the text?

A．GPS is not accurate enough.

B．Insects have better eyes than humans.

C．Light changes passing through polarized sunglasses.

D．Insects have tiny brains that use no energy.

2. What does the underlined word “simulate” in paragraph 4 probably mean?

A．Pretend.	B．Cover.
C．Block.	D．See.

3. What did Webb’s research find?

A．Insects can’t find their ways during nights.

B．Insects can find directions with little mistakes.

C．Insects always make mistakes finding directions.

D．Insects have sensing and processing equipment in their eyes.

4. Which of the following can best describe insects’ navigation ability?

A．Disappointing.	B．Interesting.
C．Amazing.	D．Confusing.