Most scientific researchers believed that mummification practices took place in 2,200BC, but a new Australian study shows that the practice was occurring much earlier – in, say, 4,500-3,500BC.

The study, conducted by Macquarie University, analyzed the tomb linens of deceased persons from Egypt’s Badari and Mostagedda that were excavated in the 1920s and 30s. Macquarie University’s Dr. Jana Jones noticed that the excavations from 80 years ago showed the presence of some petroleum ingredient that many researchers had associated with later mummification. “There was no fundamental change in the embalming mixture used some 3,000 years later. The differences lay in substitution of an ingredient, but it already contained the empirical science that would become true mummification,” Jones said.

Jones took 92 samples of evidence back to Australia for further analysis, but she also said that the samples collected are shown to have come from the tombs of wealthy individuals. The tombs not only showed the dead, but also pets and jewelry – which would not be present in the tombs of poor and impoverished individuals. It seems, then, that the early mummification period discovered in this study was a trend that started with the well-to-do upper echelon of Egyptian society.

The results of this mummification study can be found in the PLOS ONE journal.