Language is one character that distinguishes man from other animals. Words give us the power to express complicated ideas, and this skill has taken us far.

No one knows exactly when our ancestors started talking, but new evidence suggests that it might have happened a long, long, long time ago. A set of bones found last year in Central Asia shows that human ancestors living 1.8 million years ago were capable of speaking to one another. The fossils, which include several types of vertebrae (椎骨), were found at a site called Dmanisi in the country of Georgia.(格鲁吉亚) They belonged to a human ancestor known as Homo erectus (直立人).

Anthropologists (人类学家) from the University of Pennsylvania in Philadelphia and the Georgian State Museum in Tbilisi compared the fossil bones with more than 2,200 vertebrae from people, chimpanzees, and gorillas.

The structure of the ancient human’s spine (脊椎), they found, could have supported the muscles and nerves needed for speech. The new finding counters previous interpretations of a 1.6-million-year-old skeleton found in Kenya in 1984. The backbone, which belonged to a 16-year-old boy, appeared too small to support the structures necessary for speech. Now, some scientists say that the boy had simply not grown correctly. With better nutrition, his spine would probably have been bigger.

Still, the final verdict(判决) isn’t in. Some scientists say that speech began only about 50,000 years ago, roughly 150,000 years after our species, Homo sapiens (现代人), emerged on Earth. Before then, they argue, neck bones were too short to allow a full range of speech sounds from the vocal tract (声道).

However, many populations today, including Australian abori- gines (土着居民), have similarly short neck vertebrae, but that doesn’t keep these people from talking, say researchers involved in the new study.