London, March 20 (IANS): Researchers have found prehistoric flint tools that resemble "Swiss Army knife" and were used to butcher animal carcasses.

Among elephant remains some 500,000 years old at a Lower Palaeolithic site in Revadim, Israel, professor Ran Barkai of the Tel Aviv University and colleagues recently analysed 'hand axes' and 'scrapers', replete with animal residue.

The research, published recently in PLOS ONE, represents the first scientifically verified direct evidence for the precise use of Palaeolithic stone tools - to process animal carcasses and hides.

"Fracturing rocks in order to butcher and cut animal meat represents a key biological and cultural milestone," Barkai said.

"At the Revadim quarry, we found butchered animal remains, including an elephant rib bone which had been neatly cut by a stone tool, alongside flint hand axes and scrapers still retaining animal fat," Barkai said.

"It became clear from further analyses that butchering and carcass processing indeed took place at this site," he added.

Through use-wear analysis to determine their function and the Fourier Transform InfraRed (FTIR) residue analysis, the researchers were able to demonstrate for the first time direct proof of animal exploitation by flint tools.

Archaeologists have until now only been able to suggest scenarios about the use and function of such tools.

"It makes sense that these tools would be used to break down carcasses, but until evidence was uncovered to prove this, it remained just a theory," Barkai explained.

By replicating the flint tools for a modern butchering experiment, and then comparing the replicas with their prehistoric counterparts, the researchers determined that the hand axe was prehistoric man's sturdy Swiss Army knife, capable of cutting and breaking down bone, tough sinew, and hide.

The slimmer, more delicate scraper was used to separate fur and animal fat from muscle tissue.