Chimpanzee brains were made up of equal halves, or hemispheres, whereas in human brains, a subtle twist was present.

Chimpanzee brains may be more different to humans than previously thought, according to new research, which sheds light on how we developed language skills.

Scientists from the University of Edinburgh explored the phenomenon of ‘brain torque’, which is the slight twisting seen in human brains. Until now, this was also thought to exist in other primates.

The team compared existing chimpanzee brain scans from the US, with MRI scans of human brains. They found the chimpanzee brains were made up of equal halves, or hemispheres, whereas in human brains, a subtle twist was present.

While the left hemisphere was longer than the right in human brains, this was not the case in the chimpanzee brains.

Language ability has previously been linked to areas in the left hemisphere of the brain, and is also associated with asymmetry. Researchers now believe the pattern of asymmetry in human brains could be a unique feature of our species.

“Our findings highlight a special, subtle feature of the human brain that distinguishes us from our closest primate cousins and may have evolved rapidly,” explained Neil Roberts, professor of medical physics and imaging science.

“Better understanding of how this came about in our evolution could help explain how humans developed language.”

The findings have been published in the journal Neuroimage.