Some environments on our planet can be extremely unwelcoming and you might be surprised that life is even able to survive there. These are often areas where the pressure or temperature or salinity is so intense that you wouldn't survive for even a few minutes; but extremophiles on the other hand are small creatures who not only survive, but thrive in these environments. While you may have heard of these heat or salt loving organisms, did you know that there are also extremophiles who live in solid rocks?
Called endoliths, from the Greek words "inside" and "rock," this group includes all kinds of bacteria, fungi, algae, and archaea that live between the grains of rocks and minerals. Although many endoliths have the ability to live in perhaps friendlier environments, they choose to live in rocks because not many other organisms are vying for that real estate. And that real estate market is all over the world, from the lichen living in Antarctic rocks in temperatures of down to -76 degrees Fahrenheit with winds up to 200 kilometers per hour or 3 kilometers deep within gold mines in South Africa where temperatures reach 140 degrees F and air pressure is double that of sea level. The extremophiles living in these places often use the rocks they live in as a form of shelter from the extreme conditions of their environment. Many are either autotrophs, producing their own sugars from photosynthesis, or chemotrophs, relying on chemical processes for food. And just like many of the sediments that the organisms have been found in, some of the critters themselves may be millions of years old. To learn more about these hardy creatures, watch the video!