While it is known that early humans learned how to use fire over a million years ago, scientists are still trying to gain a deeper understanding about how the process happened. There are numerous theories on how early humans learned to use fire to their advantage but little empirical evidence exists to back these theories up. However, a recently unearthed excavation site in Israel may shed new light on this age-old question.

A team of researchers has recently unearthed what is left of a caveman hearth that dates back around 300,000 years in an archaeological excavation site near the vicinity of Tel Aviv, Israel. The researchers discovered the fire pit that may have been used by early humans repeatedly as a source of fire. Around the hearth, researchers found evidence of charred bones and ash that may have accumulated while early humans gathered around the fire for social gatherings. 

In addition to bones and ash, the scientists working in the Qesem Cave site also discovered small bits and pieces of prehistoric stone tools that may have been used to prepare animals for human consumption. The excavation team was comprised of professors from the nearby Tel Aviv University, including Avi Gohper and Ran Barkai. Other team members include Dr. Ruth Shahack-Gross from the Weizmann Institute's Kimmel Center for Archaeological Science. Shahack-Gross was also responsible for analyzing the samples unearthed from the site in her lab.

"These findings help us to fix an important turning point in the development of human culture - that in which humans first began to regularly use fire both for cooking meat and as a focal point - a sort of campfire - for social gatherings," says Shahack-Gross.  "They also tell us something about the impressive levels of social and cognitive development of humans living some 300,000 years ago."

Shahack-Gross found that the center of the cave, which also served as the hearth, had large amounts of wood ash. Along with the ash, Shahack-Gross also found evidence of soil and bone fragments that have been exposed to heat in the past. The analysis was conducted using infrared spectroscopy. After the initial analysis, Shahack-Gross also conducted tests on the micro-morphology of the wood ash. By hardening a lump of ash and slicing the resulting mass into thin layers, Shahack-Gross was able to examine the samples under a microscope and the results were conclusive - the site was indeed a caveman hearth from 300,000 years ago.