Elt (or extreme long-term) refers to the study of living systems that have been exposed to conditions beyond the limits of their natural endurance. These conditions may include extremely high or low temperatures, pressures, radiation levels, or toxic substances. The goal of elt research is to understand how these organisms survive and adapt to these hostile environments.
One well-known example of an elt organism is the tardigrade, a tiny creature that can withstand temperatures as low as -328 degrees Fahrenheit (-200 degrees Celsius) and as high as 304 degrees Fahrenheit (151 degrees Celsius). Tardigrades are also resistant to pressures 6 times greater than those found in the deepest ocean trenches, and they can survive being completely dehydrated for years at a time. In addition to their impressive tolerance for extreme conditions, tardigrades are also capable of withstanding large doses of ionizing radiation—enough to kill a human being within minutes.
While the tardigrade is perhaps the best-known elt organism, there are many other examples of creatures that can endure extreme conditions. For instance, some bacteria can survive boiling water or being frozen solid in ice. Other bacteria thrive in hot springs with temperatures above 150 degrees Fahrenheit (65 degrees Celsius). There are even microbes that live in deep-sea hydrothermal vents where temperatures exceed 700 degrees Fahrenheit (370 degrees Celsius)!
The ability of some organisms to thrive in such hostile environments has led scientists to believe that life may exist on other planets with similarly harsh conditions. Indeed, recent discoveries have shown that there are microbial communities living in Earth’s upper atmosphere and inside rocks miles below the surface—places where no one thought life could exist!
As we continue to explore our own planet and others like it, it’s likely that we will find even more examples of organisms capable of surviving under incredibly adverse conditions. And each new discovery will give us a better understanding of how Life itself is able to adapt and thrive in any environment imaginable.