In a study published in the journal PLOS One, the team described three tools that Paleolithic-era humans likely used: torches, fireplaces, and grease lamps.
Stone lamps with fat from cows and deer burned for long periods of time, but didn’t light the space as well as torches.
The top panel shows the light distribution of a wooden torch, compared to a portable grease lamp (middle panel), and wood fireplace (bottom panel).
Read more stories about science here.