J. Craig Venter, leader of a team that successfully decoded the human genome, now has his sights set on reading the DNA of an entire ecosystem — the Sargasso Sea, a warm swath of water in the Atlantic around the Bermuda Triangle. Working with teams he’s assembled at private biotech institutes in Maryland, Venter believes his “shotgun” technique of DNA deciphering can be adapted to quickly read the genetic code of hundreds of thousands of microbes in a sampling of seawater. Even if the method is not successful at distinguishing all of the individual genomes in an ecosystem, it should still uncover whole groups of organisms and allow researchers to track genetic changes in an ecosystem. With a solid understanding of the species makeup of an ocean ecosystem, scientists may be able to spot population shifts that could be early indicators of pollution or other environmental problems. “I think it will become the No. 1 way that environments are monitored in the future,” says Venter.