We do not know how large and complex a brain has to be to make language possible. May be chimpanzee’s brain is too small for language, but whether the brain obtained the necessary size in Homo erectus, Homo heidelbergensis, Homo
neanderthalensis, or not until Homo sapiens, will at our present state of knowledge be nothing but conjecture. Claims have often been made since the 19th century to the effect that modern humans have a «language center» in their brain, and we shall come back to this in section 1.3.
Psychologists have tried to teach chimpanzees human language. After some unseccessful attempts 40–50 years ago to teach them spoken language, some chimpanzees have been taught parts of American Sign Language, the language used by deaf people in the United States. The reasons why chimpanzees did not manage to learn to speak are probably quite numerous. They may not have sufficiently developed articulatory organs; they may lack the ability to perceive and later to articulate sounds in a particular sequence; they may lack a sufficiently developed brain in a more general sense; or all of this may be true. When the chimpanzees were allowed to use their eyes, hands and arms instead of the ears and mouths, they were more successful. Linguists have been arguing ever since how much they learnt, and we shall get involved in that discussion. Instead, we shall take a look at research around the following question: Did the Neanderthals have an anatomy that enabled them to speak?