奇速英语

Deep under the Pacific Ocean lie coral reefs colored by some algae that live with corals. Corals usually provide nitrogen (氮) to algae, and in return they get carbon (碳), which gives them energy.

In the early 1980s, a huge heat wave turned more than 90 percent of these corals a pale, lifeless white. And it was believed that about 50 percent of reefs with beautiful corals might disappear by 2030. Heat waves warmed up the same Pacific waters in the late 1990s and again in 2015—2016, but scientists noticed that these heat waves didn’t influence the reefs as badly as the first. Maybe corals have found a way to adapt (适应).

Swimming to cooler waters is not a good choice for corals, for it makes them easily hurt by the changing climate. But corals are able to adapt. Some turn to those algae that can deal well with heat. Others can use rows of tiny hairs on their bodies to “fan” away too much harmful oxygen  (O₂) let out by stressed-out algae. Certain baby corals change their own metabolisms (新陈代谢) in order to fight the warming waters. But all these adaptations can protect themselves only to some degree.

After studying and understanding these adaptations, scientists are trying to find ways to help corals fight. If researchers can make corals accept algae that can deal with heat pressure or if they energize genes (基因) that can deal with heat pressure, it will raise the corals’ chance of living through future ocean heat waves.

“When I go down to the sea and see a beautiful healthy reef with these colorful corals, I feel this pleasure of being in this underwater world,” a famous biologist says. “It will be really sad to see it dead. But that does drive you to want to use your skills and your love to help fight.”