The modern-day homes of a kind of cave-living spiders trace the long-gone southern limits of glaciers at the top of the last 【小题1】 (majority) ice age, about 22,000 years ago. Some species live 【小题2】 cold, humid caves in the Pyrenees, the Alps and the Balkan Peninsula, forming a narrow band across Europe. Researchers 【小题3】 (compare) this range with geologists" models of glacier cover during the last ice age and found the band almost 【小题4】 (exact) matched the maximum southern edges of the glaciers, with only slight variations. An expert says the creatures not only would likely not have survived if ice had covered their caves, 【小题5】 they also probably could not have survived the warmer temperatures farther from the glaciers' edge, "There was 【小题6】 balance between cool conditions and a cave that wasn't totally 【小题7】 (cover) ,he notes, "What you see now 【小题8】 (be) just the shadow of a larger ancestral distribution. ⁿ These species are indicators of geographic change since they don't move much over a lifetime or over a generation. 【小题9】 (map) the distribution of cave species could act as 【小题10】 (addition) evidence for researchers investigating past climate conditions.

A century ago, a bird called the passenger pigeon (旅鸽) lived in North America. There were so many passenger pigeons 【小题1】 people often saw thousands, even millions of birds flying overhead. However, there is not a single one 【小题2】 (leave) today. What happened on earth? How did all passenger pigeons 【小题3】 (appear) from the earth entirely at an 【小题4】(alarm) rate?

The passenger pigeon became extinct 【小题5】 two reasons. First, their habitats—the forests 【小题6】 they lived were cut down to make way for farms and cities. Second, many pigeons were 【小题7】 (illegal) shot and eaten because they were good to eat. At that time, the authorities didn’t make hunting laws to protect 【小题8】 (endanger) species, so the extinction was happening 【小题9】 (fast) than ever before.

Later, people realized the problem. Up to now, many measures 【小题10】 (take) by government to protect wildlife from extinction.

The red-crowned crane is known as one of the 【小题1】(large) crane species worldwide, reaching an 【小题2】(impress) height of approximately 150 cm. The crane has white feathers that are as pure as snow, with some black feathers on its face, neck, and wings. But what makes it really special is the bright red skin on top of its head, 【小题3】 gives it its name.

This magnificent species can be found inhabiting various regions, 【小题4】(include) China, Russia, Mongolia, Japan, and the Korean Peninsula. In China, during the warmer months, the red-crowned crane resides in rivers and wetlands 【小题5】(locate) in the northeastern parts of the country. As the temperature 【小题6】(drop), these cranes migrate to the east-central regions of China.

The red-crowned crane’s diet primarily consists 【小题7】 fish, snails, and aquatic plants. It skillfully captures its prey, displaying its agility and adaptability in aquatic habitats.

In Chinese culture, the red-crowned crane holds great symbolic significance. It 【小题8】(see) as a representation of long life and good luck. The graceful presence of this crane in folklore and traditional art highlights its esteemed status as a symbol of prosperity and vitality.

To witness the red-crowned crane in flight or observe its elegant courtship displays is 【小题9】(true) a remarkable experience. This remarkable bird’s stature, beauty, and cultural significance make it a cherished species, beloved by nature enthusiasts and those 【小题10】 appreciate the wonders of the world.