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In 2009, biologist Charles Anderson put forward an assumption that globe skimmer dragonflies (蜻蜓) on the Maldives had flown in from what he assumed was India. When they flew off again, it was towards East Africa. 12 years later, a group of researchers decided to investigate his claim.

Globe skimmer dragonflies are too small to be fitted with electronic devices. Instead, the researchers examined its physical aspects and calculated how long a globe skimmer dragonfly could stay in the air using the energy that can be stored in its body. In addition, the researchers used wind models to determine if there are winds that facilitate the migration in both directions.

“Our study shows that this migration from India to East Africa is actually possible. However, the globe skimmer dragonfly can’t manage it using only the fat in its body. It also requires favorable winds and these are present during certain periods of the year,” says Johanna Hedlund, a biology researcher at Lund University.

According to the migration experiments using wind models, about 15 percent of the dragonflies could manage the migration from India to Africa in the spring. In the autumn, 40 percent could make the same journey in the opposite direction.

Johanna Hedlund and her colleagues consider it impressive that dragonflies can do this at all. Even more impressive is the fact that the globe skimmer dragonfly migration across the Indian Ocean is the longest in the animal kingdom in relation to an animal’s size.

Other animals also rely on favorable wind conditions when they migrate. Two examples are the amur falcon and the Jacobin cuckoo, which also fly across the Indian Ocean. The researchers warn that climate change may affect the chances of these birds and the globe skimmer dragonfly in the future. There is a risk that wind patterns will change when the water surface gets warmer.

【小题1】What can be learned from the text?
A.The dragonfly flies using the fat in its body.
B.The dragonfly flies the longest in the animal world.
C.Charles Anderson spotted dragonflies flying to India.
D.15 percent of the dragonflies left Africa for the Maldives.
【小题2】How do the researchers mainly prove their assumption?
A.By fitting electronic devices.B.By giving examples.
C.By performing experiments.D.By making comparisons.
【小题3】Why are two examples mentioned in the last paragraph?
A.To illustrate how the animals fly.
B.To warn people of the climate change.
C.To evidence that water surface gets warmer.
D.To show the influence of wind on the migration.
【小题4】What’s main idea of the text?
A.Wind conditions are crucial to dragonflies.
B.Climate change may affect animals’ migration.
C.Dragonflies can migrate across the Indian Ocean.
D.Johanna and her colleagues investigate dragonflies.
2022·福建宁德·一模
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