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 Wiessner 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. Wiessner 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 percent of group conversations were storytelling, often about people living far away or in the spirit world.