Believed to have existed for more than 60 million years, crested ibises (朱鹮) are one of the oldest species of bird on Earth. Due to pollution and other human activities, the birds 【小题1】 (begin) to disappear in the 1960s. In 1981, seven crested ibises were found in Yangxian county, Shaanxi province, 【小题2】were believed to be the last remaining ones worldwide. But now, they have come back from the brink of 【小题3】(extinct). Researchers said that 【小题4】 number has risen to more than 7,000 worldwide. There are 5,000 crested ibises in Shannxi alone.

“The secret for the inspirational case of 【小题5】 (successful) saving crested ibises from a small population is the immediate onsite protection approach adopted at the very beginning,” Zhang Yueming, an expert who works at the crested ibis nature reserve in Yangxian.

【小题6】 the fourth day after the discovery of the seven crested ibises, the local government published a series of emergency notices to protect crested ibises, for example, the bans on hunting. Later, it also established the Qinling No. 1 protection station and sent four people 【小题7】 (guard) the seven birds. These guardians observed and recorded the birds’ habits and kept them safe. Meanwhile, new methods were used to protect crested ibises, mainly 【小题8】 (include) artificial breeding and reintroduction. In 1990, the Shaanxi Crested Ibis Rescue and Breeding Center was established. At the center, crested ibises are artificially bred and can receive timely treatment 【小题9】 they are sick. Over the next 30 years, they 【小题10】 (establish) a complete system of artificial breeding techniques, laying a foundation for the birds’ later reintroduction into the wild.

Every autumn, 【小题1】(million) of North American monarch butterflies begin a long and difficult journey. Somehow they manage to travel around 4,000 kilometers south and find【小题2】way to California or Mexico. However, until recently no one knew how they did this.

A team of scientists 【小题3】(lead) by Professor Eli Shlizerman at the University of Washington has now found the answer. They have found out that the monarch is able to tell the time of day. It uses its eyes to measure the position of the sun. These two pieces of information - the time of day and the point where the sun is in the sky-   allow   the   butterfly   to   determine   the   way   to   go【小题4】 (eventual), it manages to reach   the   place 【小题5】it will spend the winter.

The solution【小题6】the mystery of the monarch’s amazing ability comes at a time when it is in serious trouble.   Its population 【小题7】(crash) by as mush as 90 per cent in the last few years. Sadly, human activity is the main reason 【小题8】the number of monarch butterflies is falling. In many of the places where the butterfly can be found, people are destroying the natural environment. The research on the monarch’s behaviour has however led to【小题9】greater   awareness   of   this   creature.   People   have   been   working   together 【小题10】(record) its migration and make sure that there are enough plants for it to feed on .If this works, there may come a time when the number of monarch butterflies increases once again.

The fresh thin air, snow-covered mountains and graceful animals running on the plains are why we’re here to observe Tibetan antelopes(羚羊), which are being hunted, 【小题1】 (illegal), for their valuable fur(毛皮).

My guide is Zhaxi, 【小题2】 (work) at the Changtang National Nature Reserve. “We’re not trying to save the animals,” he says. “Actually, we’re trying to save 【小题3】 (we).”

During the 1980s and 1990s, the population of Tibetan antelopes 【小题4】 (drop) by more than 50 percent, as hunters were shooting antelopes to make 【小题5】 (profit). To save this species from 【小题6】 (extinct), the Chinese government placed it under national protection. Zhaxi and other volunteers watched over the antelopes day and night 【小题7】 (keep) them safe from attacks. Bridges and gates were constructed to let the antelopes move easily and keep them safe from cars and trains.

【小题8】 a result, the antelope population has recovered and in June 2015, the Tibetan antelope was removed from the 【小题9】 (endanger) species list. The government, however, does not intend to stop the protection programmes, since the 【小题10】 (threat) to the Tibetan antelope have not yet disappeared.

Only when we learn to live in harmony with nature 【小题11】 we stop being a threat to wildlife and to our planet.