Oceans contain much more bacteria than scientists assumed

Using a new genetic mapping technique, U.S., Dutch and Spanish scientists said they found more than 20,000 different types of microbe in a single liter (1.8 pint) of water from deep sites in the Pacific and Atlantic Oceans.

"These observations blow away all previous estimates of bacterial diversity in the ocean," said lead author Mitchell Sogin of the Marine Biological Laboratory at Wood's Hole, Massachusetts.

He said past studies had suggested that one liter of water would contain 1,000 to 3,000 types of microbe -- the oldest form of life on the planet. Microbes make up more than 90 percent of the total mass of life in the seas, from bacteria to whales.