September 3, 2013
Language And Tools Share Evolutionary Origins
Lee Rannals for redOrbit.com - Your Universe Online
Language and tool-making were two essential abilities that separated humans from apes when their evolutionary paths first diverged millions of years ago. Now, scientists say that these two traits appear to have evolved at the same time.University of Liverpool researchers have discovered that the same brain activity used for the production of language and is also required for complex tool making. To reach this conclusion, the researchers studied the brain activity of 10 expert stone makers as they created tools and took a language test.
Scientists measured brain blood flow activity using a functional Transcranial Doppler Ultrasound (fTCD) while participants performed tasks associated with tool making and language development. They found that brain patterns for both tasks correlated, suggesting that these tasks evolved from this area of the brain.
“This is the first study of the brain to compare complex stone tool-making directly with language," said Dr Georg Meyer from the University Department of Experimental Psychology and one of the authors of the study published in the journal PLOS ONE.
“Our study found correlated blood-flow patterns in the first 10 seconds of undertaking both tasks. This suggests that both tasks depend on common brain areas and is consistent with theories that tool-use and language co-evolved and share common processing networks in the brain.”
Although this may be the first study to compare the two using an fTCD, they are not the first scientists to theorize about the the possible connection. Charles Darwin, who is thought of as the father of the theory of evolution, was the first to suggest a possible link between language development and tool-use. He noticed that both depend on complex planning and the coordination of actions, but he didn't have modern technology to test the theory.
“Nobody has been able to measure brain activity in real time while making a stone tool. This is a first for both archaeology and psychology," said Dr Natalie Uomini from the University’s Department of Archaeology, Classics & Egyptology, and ao-author of the study.
Scientists from the University of Colorado say that language, art and technology all emerged about 75,000 years ago when the formation of a "super-brain" took place. He said the formation of the super-brain, or collective mind, was a consequence of the rare ability to share complex thoughts among individual brains.
“Humans obviously evolved a much wider range of communication tools to express their thoughts, the most important being language,” said John Hoffecker, a fellow at CU’s Institute of Arctic and Alpine Research. “Individual human brains within social groups became integrated into a neurologic Internet of sorts, giving birth to the mind.”