They think that as long ago as 1.5 million years, an early human called Homo erectus might have been able to talk a little. But scientists think it wasn t until the arrival of fully modern man, Homo sapiens , that people made full use of language. If this is true, people were able to tell stories, make jokes, and describe the beauty and dangers of the world around them starting about 100,000 years ago. One factor is their brain size. Baboon brains are larger than the brains of most primates, but a lot smaller than what we ve got knocking around in our heads.
Humans also have the right kind of larynx, or voice box.
In non-human mammals, the voice box is high in the neck. Its high position limits the ability to form complex sounds and speak. In adult humans, though, the voice box is deep down in the throat. Fossil File, humans are special because we walk on two legs rather than on four. From Week 2, you know that walking on two legs freed our hands to make and carry tools.