Anthropologist Find: Vesuvius turned human brain cells into glass

Irina Ziganshina

As is known in 79 AD. in southern Italy there was a catastrophic eruption of Vesuvius. A powerful pyroclastic flow - a cloud of gases, hot ash and rock debris formed during the eruption of a volcano - hit the nearby Pompeii and Herculaneum and sealed them tightly. In these extreme conditions, the flesh of the victims buried under the lava remained for centuries exactly what it was at the moment when it was exposed to a temperature of 500 ° C.

Anthropologists from the Frederick II University of Naples who participated in the excavations of Herculaneum discovered the finds, which were described in an article published in the journal of the American Medical Association JAMA.

Excavations for the Collegium of Augustals - a building in the city center that was a kind of headquarters for worshiping Emperor Augustus as a deity - revealed the remains of a 20-year-old man, apparently a member of the college. The young man's skull was cracked and charred, but inside was a shiny black material. Using an electron microscope to see the smallest details of the sample, the researchers found tiny spherical structures as well as long tubular structures that look exactly like neurons and their processes, axons.

Energy dispersive X-ray spectroscopy, in which X-rays are used to determine the chemical composition, showed that the sample was rich in carbon and oxygen, that is, organic. By comparing these ancient proteins to a database of proteins found in the human brain, the scientists found that all the proteins they found are present in brain tissue. And based on the concentration of these proteins and the fact that the sample was found in the back of the skull, Italian anthropologists suggested that they found part of the spinal cord and cerebellum.

Preserved brain tissue is a rare find in archeology. Although sometimes they can persist for hundreds and even thousands of years. For example, in the north of England in 2008, an Iron Age human skull was found that had lain there for 2,600 years, with the remains of a brain containing some proteins that remained unchanged. It is likely that the chemicals in the clay that surrounded the skull acted as preservatives, preventing decomposition. Also widely known is the case of a mummified mammoth, discovered ten years ago in Russia, near the Laptev Sea: thanks to the permafrost, the animal, 39,000 years after its death, looked as if it had died yesterday, and its brain was perfectly preserved.

Hot lava is also a preservative: the structure of brain cells is still visible in the black vitreous material found in the skull of an inhabitant of Herculaneum. “The results of our research show that a unique process of vitrification took place in Herculaneum - the transition of a liquid with a decrease in temperature to a glassy state. He froze the victim's brain structures, keeping them intact to this day”, - write the Italian anthropologists.