Bill Nye (left) and Ken Ham debated whether creation is a viable model of origins in the modern scientific era during a lengthy debate Tuesday. The points they raised have fueled an online conversation that continues. YouTube hide caption

itoggle caption YouTube

Bill Nye, left, and Ken Ham will debate the issue Tuesday at 7 p.m. ET. AnsweringGenesis.org hide caption

itoggle caption AnsweringGenesis.org

Kansas Board of Education members look over language for a science textbook in 2007. The fight over the teaching of evolution has been particularly fierce in Texas, which because of its size influences many textbook publishers. Charlie Riedel/AP hide caption

itoggle caption Charlie Riedel/AP

Charles, Prince of Wales, smells before tasting some ice cream during a visit to Gloucestershire. Maybe he was sniffing for fat? Barry Batchelor/Getty Images hide caption

itoggle caption Barry Batchelor/Getty Images

A new study on lactose tolerance among early farmers in Spain challenges a leading theory that humans developed an appetite for milk to avoid calcium deficiency. iStock hide caption

itoggle caption iStock

Say aaaaaah! Dental caries and other signs of oral disease are plain to see in the upper teeth of this hunter-gatherer, between 14,000 and 15,000 years old. The findings challenge the idea that the original paleo diet was inherently healthy, says paleo-anthropologist Louise Humphrey. It all depended, she says, on what wild foods were available. Courtesy of Isabelle De Groote hide caption

itoggle caption Courtesy of Isabelle De Groote

A display of a series of skeletons showing the evolution of humans at the Peabody Museum, New Haven, Conn., circa 1935. Hulton Archive/Getty Images hide caption

itoggle caption Hulton Archive/Getty Images

Humans and chimpanzees — like this individual at a zoo in Australia — are animals who have evolved to forge extensive and elaborate social connections. Lisa Maree Williams/Getty Images hide caption

itoggle caption Lisa Maree Williams/Getty Images

The Cathedral Spires in the Black Hills of South Dakota are just one of innumerable formations across the planet that speak to the Earth's ancient history. K. Scott Jackson/Ohio Water Science Center/USGS hide caption

itoggle caption K. Scott Jackson/Ohio Water Science Center/USGS