Archaeologists found the world's oldest piece of string. It is 50,000 years old. It shows that early humans (called Neanderthals) were very intelligent. Neanderthals all died 35,000 years ago. The string shows they understood how to make rope. They also made clothes, bags and other things. They were as intelligent as we are.
The string is very small. It shows how people lived 50,000 years ago. A researcher said she learned many things from the string. The Neanderthals made the string from different fibres. They also knew about plants and trees. They had the intelligence, "to use different parts of the environment".