Soft parts of the body normally do not fossilize. Still, an extended low-density area in the rock still inside the skull could suggest brain tissue after bacterial decay.
“We saw this cavity near the frontal part inside the skull that had a strange shape,” said researcher Paul Tafforeau, a paleoanthropologist at the European Synchrotron Radiation Facility.
“One way to explain that cavity is that when this individual died, it was mummified, and the mummification made the brain shrink by losing water, leading to an odd shape,” Tafforeau said. “Later you had water with sediment come up, fossilizing the individual and filling the brain case, but you still had that brain remnant inside.”
If it is a shrunken brain, it is perhaps one-twentieth of its original size of 420 and 450 cubic centimeters, which was already small when compared to the human brain of about 1,200 to 1,600 cubic centimeters. The shrinkage would make teasing apart its original structure virtually impossible, and the possibility of it holding any useful amounts of protein, DNA or other biomolecules is slim.
“It’s quite an unexpected discovery, but for the moment, I’m not sure we can find any important information in it,” Tafforeau said. “I hope that I’m wrong. It’s too early to say.”