Fish DNA in Ozark streams reveals region’s complex geologic history

A student collects a water sample for DNA analysis. David Duvernell, CC BY My students and I encountered a mystery. We were partnering with the Missouri Department of Conservation to monitor for fish presence and abundance in the Missouri Ozarks. We visited half a dozen rivers and streams across the region and collected a few cups of water from each. We were testing for DNA in the environment to determine which species had left behind their genetic material and were therefore present in the…