extremophiles

Geobiologist Alexis Templeton thinks it matters: We humans tend to see the world as a solid rock coated with a thin layer of life. But to scientists like Templeton, the planet looks more like a wheel of cheese, one whose thick, leathery rind is perpetually gnawed and fermented by the microbes that inhabit its innards. Those creatures draw nourishment from sources that sound not only inedible, but also intangible: the atomic decay of radioactive elements, the pressure-cooking of rocks as they sink and melt into the Earth’s deep interior—and perhaps even earthquakes. And the implications for finding life on Mars? Finding that life will be a challenge. With existing technologies, a probe sent to Mars could drill no more than Read More ›

Researchers have found some of the oldest and slowest life forms on Earth: In a bid to hone in on the lower energy limits for life, Hans Røy at Aarhus University in Denmark probed the clays below the North Pacific gyre. Under the microscope, he found a community made up of bacteria and single-celled organisms called archaea in vanishingly small numbers. “There are only 1000 tiny cells in 1 cubic centimetre of sediment, so finding just one is literally like hunting for a needle in a haystack.” The microbes rely on oxygen, carbon and other nutrients in their deep environment to live, but Røy’s team found that carbon is so limited that the cells respire oxygen 10,000 times slower than bacteria Read More ›

Careful study showed that this was not the result of contamination: In a surprise to scientists, cyanobacteria have been found thriving nearly 2,000 feet below the strange landscape, where sunlight, water, and nutrients are scarce. Researchers previously thought these microbes could survive only while basking in the sun’s rays, although they are otherwise a versatile bunch; researchers have found them alive nearly everywhere on Earth. … Control samples helped the team determine that the microbes did not come from contamination due to the drilling fluid nor from processing in the lab. And the cyanobacteria were not found in random locations, as you might expect if the samples had been doused in contaminated liquid. Instead, they were congregating along the fractures Read More ›