All social animals communicate with each other, from bees and ants to whales and apes, but only humans have developed the language which is more【M1】______ than a set of prearranged signals. Our speech even differs on a physical way【M2】______ from the communication of other animals. It comes from a speech center which does not respond instinctively, but organizes sound and meaning on a rational basis. This section of the brain is unique to humans. When and how the special talent of language developed is impossible to say. So it is generally【M3】______ assumed that their evolution must have been a long process. Our ancestors【M4】______ were probably speaking a million of years ago, but with a slower delivery, a【M5】______ smaller vocabulary and of all a simpler grammar than we are accustomed to.【M6】______ The origins of human language will perhaps remain for ever obscure. With【M7】______ contrast the origin of individual languages has been the subject of very precise study over the past two centuries. There are about 5,000 languages spoken in the world today(a third of them in Africa), but scholars group them together into relative few families—probably less than twenty. Languages are linked【M8】______ to each other in shared words or sounds or grammatical constructions. The【M9】______ theory is that the members of each linguistic group have descended from one language, a common ancestor. In many cases that original language is judged by the experts to have been spoken in surprisingly recent times—as little a few【M10】______ thousand years ago.
【M1】