Rare species can be difficult to detect, but scientists are looking to environmental DNA (traces of cells from skin, feces, and hair) to pin them down, according to The Scientist.
What they found: There are billions of cells that organisms leave behind in their environment, and they act as a marker of which species have traveled through various areas. So far, scientists studying eDNA have discovered the only cave-dwelling salamander to exist in Europe and Yangtze finless porpoise in China's Yangtze River. Bighead and silver carp in Lake Michigan, and alien and Asian carp in the Illinois and Mississippi rivers were also detected early thanks to eDNA.
Why it matters: The eDNA is helping scientists discover rare species "that are some of the most elusive animals on Earth," per The Scientist. "eDNA represents a revolution over traditional monitoring methods," Kathryn Stewart, a postdoc at the University of Amsterdam who led the study, wrote in an email to The Scientist. It is "perfectly suited for studying this cryptic, elusive, and rare species."