News ID: 194990
Published: 0805 GMT June 18, 2017

Researchers identify DNA left by ocean animals to survey marine ecosystems

Researchers identify DNA left by ocean animals to survey marine ecosystems

Researchers have shown genetic clues left behind in shed cells, tissues, scales and feces by ocean animals can be used as forensic markers to accurately and easily survey marine life in complex deep-water environments.

erWhile there is no easy method for detecting sea creatures' presence in the vast watery realm, researchers at Stanford University showed progress in using deoxyribonucleic acid (DNA) analysis to detect ocean animals in locations where the water can be nearly 2,200 meters, deep, wrote.

Elizabeth A. Andruszkiewicz, a graduate student in Stanford's Department of Civil and Environmental Engineering and lead author of a paper published in PLOS ONE, said, "We want to know what's out there.

“Eventually, this technology may answer bigger questions, such as how communities of organisms have adapted to environmental changes over time."

Of the few previous environmental DNA, or eDNA, studies of ocean animals, all were done in relatively shallow nearshore environments.

Most were done in controlled systems such as saltwater tanks. The Stanford-led study was done in the deep waters of Monterey Bay, an important ecosystem in the California Current, which flows southward along the western coast of North America.

Collecting eDNA is fairly straightforward, as a basic water sample does the trick, and researchers can archive these samples for long periods by freezing them.

The approach promises a faster and less invasive way to measure abundance and distribution of organisms.

Study coauthor Alexandria Boehm, professor of civil and environmental engineering at Stanford, said, "This could revolutionize the way we keep track of animals.”

The eDNA survey identified 72 species of vertebrates, namely marine fishes, mammals such as elephant seals, humpback whales, sharks and rockfishes, at study sites across 45 kilometers, of the Monterey Bay National Marine Sanctuary.

The researchers found DNA of some creatures, such as sunfishes, salmon, seahorses and mackerel sharks, only in locations where the water was less than 183 meters, deep.

DNA of other animals, such as dolphins and marine smelts, turned up only in waters more than 182 meters deep. The shallowest waters held the greatest biodiversity.

Taken as a whole, the findings provide a proof of concept for eDNA as an ocean sleuthing tool.

Coauthor Barbara Block, the Charles and Elizabeth Prothro Professor in Marine Sciences at Stanford, said, "It is a remarkably powerful way to answer a simple question: What species are present in space and time in our oceans?

"It could change how we view our planet's marine biodiversity."

Security Key:
Captcha refresh
Page Generated in 0/9118 sec