A recent study found that extreme environmental change could cause an “extinction domino effect.”【小题1】it may seem unimportant if we lose one rat species, it matters because all species【小题2】(connect ) through their interactions in a web of life. A balanced ecosystem is one in which each species plays an important role and relies on the services provided by other species【小题3】(survive). Healthy ecosystems are more productive and resistant to disruptions.

Researchers believe they have found a 【小题1】 (previous) unknown kind of whale in waters off Mexico’s western coast. If others confirm the finding, the new whale would be an important 【小题2】(discover) among giant animals.

The team of researchers came upon three unusual whales while 【小题3】(follow) a rare group of beaked whales (突吻鲸) on Nov. 17. The whales were near Mexico’s distant San Benito Islands,【小题4】 is about 500 km south of the U.S. border. Beaked whales usually avoid contact with humans. These animals suddenly appeared near the surface right next to the boat. It’s very rare to see a beaked whale, and to find a friendly group of beaked whales, it’s even 【小题5】 (rare).

Researchers did not realize they were seeing a possible new kind of whale until later. The group, 【小题6】(lead) by the non-profit Sen Shepherd Conservation Society, saw something different about the whales’【小题7】 (tooth) when they studied photos they took of the animals. The underwater recordings of the wholes’ calls also suggested they were different 【小题8】 all others.

The researchers are now waiting for test results on water they【小题9】(collect) near the whales. There could be skin cells in the water from the whales. If so, they will examine the DNA to confirm 【小题10】the whales are a new species.

The mountain bongo antelope (山地紫羚), one of the most 【小题1】 (endanger) animals, is likely to continue wandering in the wild for longer. Having followed 18 years of conservation efforts, staff members from the Mount Kenya Wildlife Conservancy reached a milestone this year — the first baby mountain bongo was born in the wild.

Native 【小题2】 equatorial forests, the mountain bongo is the largest and most colorful of the forest antelopes. The species 【小题3】 (see) a dramatic decline in numbers in the last few decades from 【小题4】 estimated population of 25, 000 to less than 100. It was mostly humans who caused its population to decrease 【小题5】 (dramatic). Now the Conservancy is making efforts in partnership with the Kenyan government to help the mountain bongo through one 【小题6】 (create) breeding (饲养) and rewilding program.

“Due to the massive decline, we 【小题7】 (leave) with less than 100 of the species in the wild. The mountain bongo is only found in Kenya and its decline in this area therefore means its decline in the world. That explains 【小题8】 taking immediate action here is so urgent,” Robert Aruho from the Conservancy said. He added that 【小题9】 (enable) the animals to adapt to life in the wild, they had taken a series of measures. With the first phase of the 【小题10】 (adapt) being complete, the Conservancy has moved to the second phase which involves introducing the antelopes to the wild.