Life In Extreme Environments

Extremophiles: These are organisms that thrive in conditions that would kill almost anything else, from boiling hydrothermal vents and acid rivers to frozen deserts and rock kilometers underground; they have rewritten the limits of life and shape where scientists search for it on other worlds.

Thermus aquaticus: Found in a Yellowstone hot spring in the 1960s, this heat loving bacterium supplied the enzyme that made PCR possible, the technique behind DNA fingerprinting and COVID tests.

Grand Prismatic Spring: The rainbow rings around Yellowstone's largest hot spring are not minerals but mats of microbes, each color band marking a different species adapted to a different water temperature.

Methanopyrus kandleri: One strain of this deep sea microbe can still reproduce at 122°C, the highest temperature known for life.

Alvin: In 1977 scientists in this deep sea submersible found thriving communities of giant tube worms and clams around hydrothermal vents near the Galápagos, ecosystems fueled by chemicals instead of sunlight.

Pompeii Worm: Living in tubes on hydrothermal vent chimneys, it may tolerate one of the steepest temperature gradients of any animal, with its tail end in scalding water and its head in far cooler water.

Lost City Hydrothermal Field: Discovered in 2000 in the mid Atlantic, its towering white chimneys vent alkaline fluid instead of acid and have been active for at least 30,000 years, a leading model for where life began.

Tardigrade: In 2007 these half millimeter 'water bears' survived exposure to the vacuum and radiation of open space on the FOTON-M3 mission, and some reproduced afterward.

Deinococcus radiodurans: Nicknamed Conan the Bacterium, it survives radiation doses thousands of times higher than would kill a human by rapidly stitching its shattered DNA back together.

Chernobyl: Black, melanin rich fungi were found growing on the walls of the ruined reactor, and some studies suggest they may even use radiation as an energy source.

Rio Tinto: This Spanish river runs blood red and about as acidic as lemon juice, yet teems with microbes, making it one of NASA's favorite stand ins for ancient Mars.

Dallol: In Ethiopia's Danakil Depression, some hot, hyperacidic, salty pools here appear to be completely sterile, one of the rare places on the surface of Earth where life seems unable to survive.

Dead Sea: Despite its name, after unusually rainy winters its surface water has bloomed red with salt loving algae and microbes, as recorded in 1980 and 1992.

Don Juan Pond: This shallow Antarctic pond is so salty it stays liquid at temperatures around minus 50°C, and scientists still debate whether anything can live in it.

Atacama Desert: Some parts of this Chilean desert went centuries without meaningful rain, yet microbes survive by hiding inside salt crusts and rocks that pull moisture from the air.

Lake Vostok: Buried under nearly 4 kilometers of Antarctic ice and sealed off for millions of years, this giant subglacial lake is a model for the hidden oceans of moons like Europa.

Wood Frog: Each winter it freezes nearly solid, with its heart and breathing stopped, then thaws and hops away in spring, protected by glucose that acts as natural antifreeze inside its cells.

Antarctic Icefish: These fish have no red blood cells or hemoglobin at all, with clear blood that works only because the icy Southern Ocean holds so much dissolved oxygen.

Mariana Snailfish: This small, translucent fish lives around 8,000 meters down in the Mariana Trench, where the pressure is like having an elephant stand on your thumb.

Saharan Silver Ant: It forages in the midday heat when predators hide, protected by triangular silver hairs that reflect sunlight and help it survive body temperatures above 50°C.

Mponeng Gold Mine: Nearly 3 kilometers underground in South Africa, scientists found Desulforudis audaxviator, a bacterium that lives alone in an ecosystem of one species, powered indirectly by radioactive decay in the rock.

Movile Cave: Sealed off from the surface for over 5 million years, this Romanian cave supports spiders, scorpions and leeches that live on a food chain built from chemical energy, not sunlight.

Lechuguilla Cave: Bacteria isolated deep in this New Mexico cave for millions of years turned out to be resistant to modern antibiotics, proving resistance is ancient and not just caused by medicine.

Loricifera: In 2010 researchers reported that tiny members of this group living in the oxygen free L'Atalante basin under the Mediterranean may be the first animals known to spend their whole lives without oxygen.

Watermelon Snow: Pink and red streaks in summer snowfields come from cold loving algae with a red pigment that works like sunscreen, and they even speed up snow melt by darkening the surface.