Global warming could make humans shorter, warn scientists who are said 【小题1】(find)evidence that it caused the world’s first horses to shrink nearly 50 million years ago.
In fact, a team from the universities of Florida and Nebraska says it has found a link between the earth 【小题2】(heat)up and the size of mammals — horses. The scientists used fossils to follow the evolution(进化)of horses from their earliest 【小题3】(appear)56 million years ago.
“As temperatures went up, 【小题4】(they)size went down, and vice versa; at one point they were as small as a house cat,” said Dr. Jonathan Bloch, curator of the Florida Museum of Natural History. The scientists say that the current warming could have the same effect 【小题5】 mammals — and could even make humans 【小题6】(small).
Horses 【小题7】(start)out small, about the size of a small dog like a miniature schnauzer.【小题8】 is surprising is that after they first appeared, they then became even smaller and then dramatically increased in size, and that 【小题9】(exact)agrees with the global warming event. “It had been known that mammals were small when it was warm,【小题10】 we hadn’t understood that the temperature really was driving the evolution of body size,” Dr. Bloch said in the Science journal.