Stone age humans took two million years to develop brain power

London: Stone age humans took nearly two million years to develop the brain power to make sophisticated tools like hand-held stone axes, a new study has claimed.

According to the researchers, the ability to form language and to design advanced tools occurs in the same part of the brain and so these skills were likely to have developed in humans at around the same time.

Lead researcher Dr Aldo Faisal was quoted by the `Daily Express` as saying, "The advance from crude stone tools to elegant hand-held axes was a massive leap for our ancestors."

The study, published in the `PLoS One` journal, employed a craftsman called a flintnapper to copy ancient tool -making techniques while being monitored.

Computer modelling using tiny sensors embedded in a "data glove" assessed the hand skills needed to make a crude sharp stone from the Lower Palaeolithic period, which began around 2.5 million years ago, and then a hand-held stone axe dating from near the end of the period.

Dr Faisal said: "We found there was no difference between hand movements for a two-million-year-old tool and the 200,000-year-old tool.

"So it is highly likely it was brain function and not dexterity limitations holding back prehistoric man. We also found that when creating the hand-held axe a part of the brain associated with language lit up."

Computer tool mapping will now investigate modern tools to improve designs. Dr Faisal said: "As we get older,
we are slower, more fragile and find it more difficult to use tools. This technique can discover what tools are easier to use and pass this information to manufacturers."

In the future, the scientists also plan to use their technology to compare tools made by Neanderthals, an extinct ancestor of humans, to glean insights into their brain development.