Message in a bottle: Forensics meets marine science with eDNA

It doesn’t look like much. At a glance, it seems Mark Stoeckle is holding a bottle of water to quench his thirst. But there’s so much more than H2O in that small plastic bottle. 

Dr. Stoeckle pours the fluid through a special filter atop a glass contraption that looks a bit like a pour-over coffee maker. A yellowish gunk collects on the filter. Clearly this liquid isn’t potable. It’s seawater the scientist collected in Barnegat Light, New Jersey. 

And that slime? That’s actually the stuff he wants. It potentially contains cells, or bits of cells, from as many as 20 species of fish that sloughed off into the water as the fish were going about their business. By sequencing the