A number of possibly ritualistic objects were found to have been deposited in several pits, including the skull, which had belonged to a man probably in his 30s.

It is not clear why the Heslington brain survived, although the presence of a wet, anoxic environment underground seems to have been an essential factor, and research is still ongoing to shed light on how the local soil conditions may have contributed to its preservation.

The site where the brain was discovered is about 3 kilometres (1.9 mi) south-east of York city centre on the eastern edge of Heslington village.

[5] The inhabitants seem to have relocated during the Roman period to a site further up the ridge, leaving the area of the Iron Age settlement to revert to fields.

Jim cleaned it up and recorded it but had to leave, so the task of lifting the skull fell to his colleague and friend Rupert Lotherington.

She said later that it "jogged my memory of a university lecture on the rare survival of ancient brain tissue ... we gave the skull special conservation treatment as a result and sought expert medical opinion.

J1d has been identified previously in only a few people from Tuscany and the Middle East; it may have been more widely present in Britain in the past, and lost through genetic drift.

[3] The presence of such an environment is thought to have been responsible for a similar but less complete preservation of brain matter discovered in the 1990s during the construction of a new magistrates' court in Hull.

There had also been a major decrease in the amount of proteins and lipids and their replacement by fatty acids and other substances produced as degradation products.

Much of the original substance of the brain has been replaced by a high molecular weight, long-chain, hydrocarbon material that is as yet unidentified.

In this particular case, the head was severed from the alimentary tract and drained of blood, so the intestinal bacteria did not have an opportunity to contaminate it.

The precise mechanism by which the Heslington brain was preserved is unclear, however; in a bid to shed light on this question, researchers buried a number of pigs' heads in and around the campus to see what happened to them[needs update].

[7] In a paper published on 8 January 2020 in the Journal of the Royal Society Interface, Axel Petzold et al performed molecular studies on a sample of the brain, and identified over 800 proteins.

This may partly explain how the Heslington brain has been able to stave off decomposition, in addition to the wet, anoxic environment in which the skull was found that could have prevented aerobic microorganisms from surviving.