SILOAM SPRINGS — Bryan Austin of Siloam Springs thought he’d found a crime scene when he spotted a human skull under a pile of rocks while he was duck hunting in northeast Oklahoma. Looking for a good place to set up a camouflage hunting screen Nov. 19 on a mud flat in the Spavinaw Creek drainage area, Austin found what turned out to be an ancient skull. He later learned that the site is an ancient Indian burial ground. “ It’s absolutely amazing, ” Austin said. “ I’m incredibly interested in this kind of stuff. It’s in my line of...