Snotites are slimy, dripping cave formations that resemble stalactites
but look and feel like snot. They are actually enormous colonies of bacteria
(often chemoautotroph extremophiles
) that metabolize sulfur-containing minerals in groundwater known as Thiobacilli
The cave environment rich in snotites usually contains an abundance of hydrogen sulfide
gas, creating a smell of rotten eggs. The area in which the bacteria thrive is so acidic that pH
readings are often negative; drops of liquid that fall from the ends of snotites are acidic enough to dissolve clothing. The cause of this acidity is a combination of the formation of sulfuric acid through the reaction between hydrogen sulfide
gas and oxygen gas as well as the releasing of sulfuric acid
as a waste product of the bacteria.
The bacteria eventually form thick sheets of slime which gradually begin to drip from the ceiling. As the colonies grow, they release more and more sulfuric acid
, which gradually begins to eat away at the rock. These tiny microbes are often responsible for carving out vast underground labyrinths; geologists believe that some cave networks were first formed by bacteria thriving deep underground, feasting on oil reserves
and releasing hydrogen sulfide.
Research on snotites
The existence of such microbes has led to speculation that similar subterranean lifeforms may exist on Mars.
DNA analysis of these bizzare microbes has aided in the discovery of new species of bacteria, protists, and nematodes.
Scientists are continually improving techniques used to grow cultures of such bacteria in lab so that the physiology and biochemistry of the organisms can be studied more easily.