Skull found at site of York University 's $ 745 million campus expansion . Investigator spotted an unusual yellow substance inside the skull . Hospital scanner used to produce clear images of the brain tissue . Expert : Dr Sonia O'Connor , Research Fellow in Archaeological Sciences at the University of Bradford added : `` The survival of brain remains where no other soft tissues are preserved is extremely rare . " The yellow stuff is a protein that looks like it might be in there for some reason, but we don't know what purpose it serves or how it got there.
Skull found at site of York University 's $ 745 million campus expansion . Investigator spotted an unusual yellow substance inside the skull . Hospital scanner used to produce clear images of the brain tissue . Expert : " The yellow stuff is a protein that looks like it might be in there for some reason, but we don't know what purpose it serves or how it got there.