By Will Dunham

Dec 10 (Reuters) - Scientists have discovered the oldest-known evidence of fire-making by prehistoric humans in the English county of Suffolk - a hearth apparently made by Neanderthals about 415,000 years ago - revealing that this milestone for our evolutionary lineage occurred far earlier than previously known.

At an old clay pit ​for making bricks near the village of Barnham, the researchers found a patch of heated clay, some heat-shattered flint handaxes and two pieces of iron pyrite - ‌a mineral that creates sparks when struck against flint to ignite tinder - that they identified as a repeatedly used campfire.

It was situated near a watering hole where these humans encamped.

"We think humans brought pyrite to the site ‌with the intention of making fire. And this has huge implications pushing back the earliest fire-making," said archaeologist Nick Ashton, curator of Palaeolithic Collections at the British Museum in London and leader of the research published on Wednesday in the journal Nature.

Until now, the earliest-known evidence of fire-making was from about 50,000 years ago at a site in northern France, also attributed to Neanderthals.

The controlled use of fire was a landmark event for the human evolutionary lineage, not only for cooking and providing protection from predators but for providing warmth that enabled hunter-gatherers to thrive ⁠in areas with colder environs.

"Places like Britain, for example," British Museum ‌archaeologist and study co-author Rob Davis said.

Through cooking, our forerunners were able to eliminate pathogens from meat and toxins from edible roots and tubers. Cooking made these foods more tender and digestible, freeing up bodily energy from the gut to fuel development of the brain.

Being able to ‍consume a greater range of foods supported better survival and allowed for feeding larger groups of humans, according to the researchers.

Fire also may have contributed to social evolution. The use of fire at nighttime allowed these humans to gather and socialize, perhaps engaging in storytelling and developing language and belief systems.

"The campfire becomes a social hub," Davis said.

"We're a species who have used fire to really shape ​the world around us," Davis said, noting that the new findings show that this trait is something our species Homo sapiens has in common with the Neanderthals and possibly ‌other large-brained human relatives living at that time like the Denisovans.

The Palaeolithic, or Old Stone Age, site at Barnham dates to before the earliest-known Homo sapiens fossils in Africa.

The researchers believe that Neanderthals, our close evolutionary cousins, were the fire-makers, another piece of evidence showing the intelligence and ingenuity of these archaic humans long maligned in popular culture.

Paleoanthropologist and study co-author Chris Stringer said no human fossil remains were found at the Barnham site.

But Stringer noted that pieces of a human skull about 400,000 years old characteristic of a Neanderthal were found in the mid-20th century less than 100 miles (160 km) to the south at a town called Swanscombe. Stringer said the Swanscombe skull fragments match Neanderthal fossils from a site ⁠called Sima de los Huesos, meaning "Pit of the Bones," near Burgos in Spain, dating to about 430,000 ​years ago.

"Thus the Barnham fire-makers were very likely to have been early Neanderthals, like Swanscombe and the Sima ​people," Stringer said.

Neanderthals went extinct roughly 39,000 years ago not long after Homo sapiens swept through the European territory they called home. Their legacy lives on in the genomes of most people on Earth, thanks to interbreeding between Homo sapiens and Neanderthals before their disappearance.

Previous archaeological work at ‍the site has given scientists a good understanding ⁠of what the place was like at the time the hearth was made, with a rich array of animals from elephants to smaller mammals and birds, and evidence of human activity in the form of cut marks on animal bones.

There is archaeological evidence from Africa dating to more than a million years ago of humans ⁠using naturally occurring fire - from wildfires or lightning strikes - but those sites lacked evidence of deliberate fire-making.

The researchers spent four years conducting tests to show that the evidence from Barnham was of deliberately made fire. They ‌said numerous pieces of evidence demonstrated this including geochemical testing that revealed there had been temperatures of more than 700 degrees Celsius (1290 degrees Fahrenheit) with ‌repeated fire-use in the same location.

(Reporting by Will Dunham in Washington; Editing by Daniel Wallis)