None of the recently discovered planets outside the solar system show signs of water or atmospheric chemistry indicative of life below. The two seemingly opposite environments have become linked as scientists study newly discovered microbes thriving in the scalding, lava-heated vents deep in the sea and wonder if such primitive, but tenacious life could arise elsewhere. The deep, hot biosphere In 1977, a small submarine dubbed Alvin descended to about 8,000 feet near the Galapagos Islands where the sea floor was cracking under the pressure of volcanic activity. As the searchlights scanned the sea floor, they revealed among the barren expanses dense communities of life clustered around vents spewing lava-heated water and debris into the frigid surroundings. Researchers were astonished to discover the food chain here was built upon previously unknown forms of heat-loving microbes.
Temperatures can only go so high before all biochemistry becomes impossible.
Some can endure intense cold while others can withstand crushing pressure or toxic environments that would kill the mesophiles of this world, or those creatures that prefer medium conditions. But since medium conditions are unique to Earth as far as we know, scientists have found the extremes much more interesting to study as they explore how life could develop on other planets. Many scientists now regard deep-sea thermal vents as a dark window into the primordial conditions that gave rise to life billions of years ago when Earth was far less hospitable. One of the most hotly debated new ideas, known as the theory of the deep, hot biosphere, turns the traditional explanation of genesis upside down. It is far more likely that life began deep within the planet.