One of the 146,000-year-old stone cores used to make butcher's tools, found in Lingjing, China. Photo by Yuchao Zhao. Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. A remarkable collection of ancient stone tools proves that human creativity can thrive in challenging times. The complexity of the stone tools found amidst the bones of butchered animals in central China demonstrate an elevated level of intelligence and creativity. Early humans forged the tools during an ice age 146,000 years ago, not during the relative ease of a warm period. According to a study published today in the Journal of Human Evolution , this challenges the idea that the early humans  could not innovate.  “People often imagine creativity as something that flourishes in good times,” Yuchao Zhao , a study co-author and the assistant curator of East Asian archaeology at the Field Museum in Chicago, said in a statement .…