First migration from AfricaBy Nancy Steinbach
This is Bill White with the VOA Special English SCIENCE REPORT.
Scientists say the ancestors of humans first developed in Africa. Fossil bones found there are older than human remains found anywhere else. Now scientists digging in the nation of Georgia say they have found fossils of the first human-like creatures to leave Africa.
The two head bones were found last summer in the Georgian city of Dmanisi, in the Caucasus Mountains southwest of the capital, Tbilisi. The discovery team included scientists from France, Germany, Georgia and the United States. Results of the team's research were reported recently in the publication Science.
The scientists say the fossils are bones of the oldest human ancestors ever found in Europe or Asia. They are about one-million-seven-hundred-thousand years old. The bones are very similar to fossils that have been found in East Africa.
The scientists say this is the best evidence yet that human-like creatures left Africa much earlier than had been thought. It supports the idea that human ancestors left Africa just after they had developed into more modern creatures. Human ancestors changed over a long period of time from having short legs and long arms to having short arms and long legs that could walk long distances.
The scientists also found animal bones and more than one-thousand stone tools near the human fossils. The discovery of these tools disputes a theory about the earliest humans.
Scientists had thought that human ancestors left Africa soon after they invented improved tools such as stone axes. But the tools found in Georgia are similar to the simpler tools that have been found in Africa. This means the creatures moved before they invented improved tools. Scientists think these human ancestors left Africa to follow large groups of animals that they could kill for food. They say that when human ancestors began eating meat, they were forced to expand their territory to find food.
The scientists say the fossils found at Dmanisi are not similar to remains found later in Europe. They say that the discovery suggests that the creatures first moved from Africa to the Caucasus area. They moved to nearby areas of Europe much later.
This VOA Special English SCIENCE REPORT was written by Nancy Steinbach. This is Bill White.