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Many science fiction stories tell about explorers arriving in a new world. The explorers use some kind of high-tech device to test for breathable air or signs of life. But here on Earth, science fiction is becoming reality through a new sampling technology called environmental DNA, or eDNA for short. Scientists can use it to identify rare or invasive species, study biodiversity or estimate fish populations with just a little air or water. Ryan Kelly is an ecologist at the School of Marine and Environmental Affairs at the University of Washington in Seattle. He works in a laboratory there with other researchers. They study the genetic material released by living creatures. Ryan Kelly says he and his research team are studying water samples collected from Puget Sound. He says the cost of gene sequencing has gone down sharply in recent years. That makes DNA testing more widely available. Environmental DNA can be used in two ways. One is to identify the creatures that live in a certain place. The other is to confirm the presence or lack of a specific creature. Caren Goldberg heads the new eDNA lab at Washington State University in Pullman, Washington. She is one of the first biologists in the northwestern United States to use the technology. She says it helps her study species that are hard to find. Caren Goldberg sees eDNA as a way to get answers more efficiently, safely and with less destruction compared to traditional methods. A related research goal is to show how long environmental DNA can last and how far it can travel in different environments.