This is Scientific American 60 Second Science.

I'm Cynthia Graber.

Got a minute?

Some scientists say the use of fire helped make us modern humans.

It dramatically changed what and how we eat and may have even

altered our anatomy. But University of Utah anthropologist Polly Weisner

thinks that Fire was also important in shaping human social interactions and

cultural traditions.

Her conclusions are in the proceedings of the National Academy of Sciences.

Wiesner evaluated day and night activities and conversations of Kalahari Bushmen from Botswana and Namibia.

These communities still live by hunting and gathering, as most humans did over evolutionary history.

During the day, nearly a third of the conversations dealt with economic issues such as hunting strategies and

foraging plans. Another third covered complaints, criticisms, and gossip. But at

night, around the fire, more than 80% of group conversations were storytelling, often about people living far away or in the spirit world.

Wiesner says that humans are unique in that we create ties to others outside of our immediate group.

Gathering at the fire expanded listener's imaginations and

allowed for the development of cognitive processes that made it possible to

form those links to distant communities which makes fire the precursor to Facebook.

Thanks for the minute.

For Scientific American 60 Second Science, I'm Cynthia Graber.