Common Ancestor Of Complex Life Lived Near Underwater Volcanic Vents

There is a fascinating story in the Science section of the New York Times about the origins of complex life. A recent study created a genetic portrait of an organism that looks to be the common ancestor to the two earliest domains of life - bacteria and archaea (bacteria with a different metabolism than regular bacteria). The 355 common genes of that ancestor "pointed quite precisely to an organism that lived in the conditions found in deep sea vents, the gassy, metal-laden, intensely hot plumes caused by seawater interacting with magma erupting through the ocean floor", according to the study. Apparently, this ancestor organism names LUCA, an acronym for Last Universal Common Ancestor, was able to internalize the energy producing features of what is called a "proton gradient" that occurs near these volcanic vents where energy is produced by the interaction of the proton rich water near the vents and the proton-poor water further away. Read the whole story to perhaps get a better idea than my description or also read a book that posited this theory called The Vital Question by Nick Lane for an even deeper discussion (thanks to Kevin Drum at Mother Jones for provided that book).

In any case, this certainly has major implications for life beyond our planet as we are beginning to discover that volcanic activity that could produce similar or different kinds of a proton gradient is much more prevalent than previously thought on planets and moons in our solar system and that would similarly be the case for planets and moons circling other stars in the universe.