Catching nearly 4,000 wild butterflies with handheld nets and taking the temperature of each tiny insect must rank among the harder of scientific efforts.

However, researchers have discovered significant differences in the ability of British butterflies to maintain a suitable temperature, raising fears that global heating will threaten the populations of some species.

Butterflies are ectotherms-unable to generate their own body heat-and require warm temperatures to fly. However, extreme temperatures can pose problems, particularly for those butterflies that must find shady habitats to regulate (调节) their body temperature.

The study shows that larger, paler butterflies are best able to protect themselves from extreme temperatures, changing the angles of their reflective wings in relation to the sun to direct heat away from or on to their bodies. Darker, large species have greater difficulty controlling their body temperature, but even they are better than “thermal specialists”, which rely on finding a spot at a specific temperature in a landscape-a “microclimate”-to control their body temperature.

“After being caught in butterfly nets on British nature reserves, the 29 different species of butterflies’ temperatures were taken with a fine probe. As we plan conservation measures to address the effects of climate change, it will be important to understand not only the habitat requirements of different butterfly species, but also their temperature requirements,” said Dr Ed Turner, of the University Museum of Zoology, Cambridge, who led the work. “With this new understanding of butterflies, we should be able to better manage habitats and landscapes to protect them, and in doing so we’re probably also protecting other insects too.”

【小题1】Why did scientists take the temperatures of butterflies?

A．To seek solutions to global heating.

B．To uncover climate threats to them.

C．To classify them into different species.

D．To stress the toughness of scientific research.

【小题2】How do larger, paler butterflies regulate their temperature?

A．By angling their wings.

B．By generating the body heat.

C．By choosing a microclimate.

D．By making use of their colour.

【小题3】On what basis do butterflies seek specific locations?

A．Finding a nature reserve.

B．Attracting other butterflies.

C．Adapting to climate change.

D．Perceiving the surroundings.

【小题4】What can we learn from the last paragraph?

A．Understanding butterflies should be strengthened.

B．Better management of butterfly habitats is popular.

C．Protecting butterflies can lead to additional benefits.

D．Goals of protecting butterflies have been achieved.