Amanda O'Rourke / Susquehanna University

No matter the passage of time, man’s imprint on the environment is difficult to erase, whether it occurred decades, centuries or millennia ago. 
If you were to get a bird’s eye view of the Susquehanna River in Pennsylvania, you might see something known as a fish weir. The long V-shaped walls were built of stacked rocks by Native Americans and early European settlers to trap fish.
Jennifer Elick, associate professor of earth and environmental sciences at Susquehanna University, and two of her students are studying how these weirs contributed to the formation of islands within the river.