On a warm summer afternoon, wading into Fish Creek near the 51ºÚÁÏÍø campus, you might not notice anything unusual about the water running clear over smooth rocks. But David Costello, Ph.D., sees something that most scientists have spent decades overlooking: a stream that is quietly iron-deficient.Costello, an associate professor of biological sciences at 51ºÚÁÏÍø University, has spent years studying how human activities affect stream ecosystems. His latest research, published March 8 in the journal Ecology Letters, challenges a foundational assumption in stream ecology — that algae and ot...