TAMARA KEITH, HOST:
Ever sat around a campfire roasting s'mores? Well, campfires like that went mainstream among early humans at least 400,000 years ago, though maybe not for s'mores.
RAN BARKAI: Fire was used mainly for cooking, for warmth and roasting meat. So it is clearly that barbecue started 400,000 years ago.
ARI SHAPIRO, HOST:
Ran Barkai is an archaeologist at Tel Aviv University. And he says there's a paradox in prehistoric fire use. How do you build one indoors in a cave?
BARKAI: When you make fire in a closed chamber, there is a danger of inhaling smoke. And this is not good for the health. And in many cases, it does not allow one even to stay near the fire because of the smoke.
SHAPIRO: In fact, modern scientists have tried this. And within half an hour, smoke sent them fleeing from the cave.
KEITH: Barkai and his team wanted to learn more about how early humans like Neanderthals might have pulled it off. So they built a virtual model of Lazaret Cave on France's Mediterranean coast, a place people called home 170,000 years ago. They placed 16 hypothetical hearths throughout the cave and studied where the smoke went.
BARKAI: And we found out that at the middle of the cave is the optimal place if you wish to avoid as much smoke as possible but to be able to work around the cave.
SHAPIRO: As it happens, the middle of the cave is exactly where prehistoric people put their fires for generations.
BARKAI: It is clear to us that once they entered, they made the surview of the cave, and they invited the Neanderthal internal designer. And they decided, we'll put the kitchen here. We'll put the sleeping area over here and so on. I'm not kidding.
SHAPIRO: The work appears in Scientific Reports.
KEITH: Sarah Hlubik of George Washington University was not involved in the study, but called it clever.
SARAH HLUBIK: What I would like to see most is to take a look at other sites that have relatively intact caves and see if this bears out.
KEITH: She says the work shows how early humans use their smarts to deal with a punishing climate.
HLUBIK: It was really cold (laughter). It was not like the south of France today. So they had to make a really intelligent decisions about where they lived, how they utilized those spaces.
And what's interesting is that we can see that Neanderthals were making those choices, and probably, you know, other humans at the same time were making those choices. And they were just as smart as we are.
SHAPIRO: Something to keep in mind next time you, modern human, are struggling to start a campfire.
(SOUNDBITE OF BILLY JOEL SONG, "WE DIDN'T START THE FIRE") Transcript provided by NPR, Copyright NPR.
