A rendering of Neanderthals cooking and eating. The ancient humans inhabited Europe and western Asia between 230,000 and 29,000 years ago. Mauricio Anton/Science Source hide caption

itoggle caption Mauricio Anton/Science Source

Love your hair. Artists' depictions of a Neanderthal man and woman at the Neanderthal Museum in Mettmann, Germany. Martin Meissner/AP hide caption

itoggle caption Martin Meissner/AP

Research excavations like these in Siberia's Denisova Cave are yielding clues to the mating choices of early hominids. Bence Viola/Nature hide caption

itoggle caption Bence Viola/Nature

A piece of red ochre with a deliberately engraved design is pictured here at Cape Town's Iziko/South African Museum in 2002. The piece was discovered in Blombos Cave near Stilbaai, about 300 kilometers from Cape Town. Anna Ziemenski/AFP/Getty Images hide caption

itoggle caption Anna Ziemenski/AFP/Getty Images