A cache of prehistoric tools used by ancient humans living in what is now the UK has been confirmed to be at least 560,000 years old. The artifacts are the oldest of their kind known from the UK and among the earliest known in Europe.
Archaeologists first found ancient hand axes at the site in Fordwich, Canterbury, in the 1920s. But their age was unclear.
Alastair Key at the University of Cambridge and his colleagues used a modern dating technique to determine the ages of several of the tools, which are now stored in the British Museum. They also conducted fresh excavations at the site and uncovered more evidence of ancient human activity.
The hand axes may have been used to butcher animals and to process animal skins for making clothes. “Early humans probably needed animal skins to keep warm,” says David Bridgland at Durham University in the UK, who worked on the study.
The team used a method called infrared radio-fluorescence dating to establish how old the tools were. This method involves dating the sand in which the tools were buried, and was made possible because the new excavations helped establish which layer of sand at the site had contained the hand axes found a century ago.
The technique works by establishing when the sand grains were last exposed to daylight. “This provides a signal for how long [the tools] have been buried,” says Bridgland.
The team estimates that the tools are about 560,000 to 620,000 years old. This makes the hand axes among the earliest found in Europe. But they are still relatively young compared to hand axes found in Africa, some of which are over a million years old, says Bridgland.
“These are important findings,” says Chris Stringer at the Natural History Museum in the UK. “Although we have even earlier stone tool assemblages [in the UK] from Happisburgh in Norfolk and Pakefield in Suffolk, these do not include hand axes, making the Fordwich examples the oldest well-dated ones from Britain, and among the oldest known hand axes in Europe.”
“We don’t know the human species responsible but the age of about 600,000 years is close to that of the Mauer sandpit in Germany, which produced the jawbone of Homo heidelbergensis, which could have been the species responsible,” says Stringer.