How apes 'talked' 40m years ago: Our primate ancestors developed capacity for language, scientists say
Our ancient primate ancestors developed the capacity for language 30 to 40million years ago, scientists believe.
The crucial ability to understand relationships between words in a sentence came long before modern Homo sapiens, they said.
Our arrival about 200,000 years ago is thought to have been when the building blocks of language began to take shape.
However the concept of the links between groups of sounds came long before that, said researchers at the universities of Warwick and Zurich.
Our ancient primate ancestors developed the capacity for language 30 to 40million years ago, scientists believe. Pictured: Australopithecus Afarensis, one of our most ancient ancestors that lived between 3.9million and 2.9million years ago
They examined the way chimpanzees, monkeys and humans processed tones in a string of sounds, which are much like words in a sentence.
The study looked at elements next to one another, known as an adjacent dependency, and those apart from one another or non-adjacent dependency.
There were 'notable similarities' as all three species could process both types, reported the journal Science Advances.
Professor Simon Townsend at the University of Warwick, who led the study, said: 'This indicates that this critical feature of language already existed in our ancient primate ancestors, predating the evolution of language itself by at least 30 - 40 million years.'
The team said that being able to process relationships between words in a sentence is one of the key cognitive abilities underpinning language.
Researchers examined the way chimpanzees, monkeys and humans processed tones in a string of sounds, which are much like words in a sentence. Pictured: Chimpanzees in Tanzania
One example they gave which highlighted this phenomena was the sentence: 'The dog who bit the cat ran away.'
In this sentence, it is understood that is it the dog who ran away rather than the cat, a result of being able to process the relationship between the first and last phrases.
Dr Stuart Watson, from the University of Zurich, added: 'Most animals do not produce non-adjacent dependencies in their own natural communication systems, but we wanted to know whether they might nevertheless be able to understand them.'
For this study, the researchers created 'artificial grammars' - where sequences made up of meaningless sounds instead of words were used to examine the abilities of the test subjects to process the relationships between sounds.
They found that all three species were readily able to process the relationships between both adjacent and non-adjacent sound elements.
This meant apes and monkeys were able to track relationships between sounds the same way as humans, showing that this ability predates the evolution of language itself by millions of years.
The study authors wrote: 'These notable similarities between monkeys, apes, and humans indicate that nonadjacent dependency processing, a crucial cognitive facilitator of language, is an ancestral trait that evolved at least 40 million years before language itself.