Hydrothermal vents: A unique geographical phenomenon
Hydrothermal vents are submarine chimneys which spew almost boiling hot water emerging from the earth crust at often great depths along with very toxic chemicals.
This is how hydrothermal vents are formed
The cold seawater fissures through the crust of the seafloor where two tectonic plates meet, which either are moving away from each other or being squeezed together. The seawater is heated by hot magma and may reach temperatures over 340°C and then re-emerges through the crust. The hot seawater doesn’t boil due to the pressure in the deep. When the extremely hot water, emerging from the crust meets the ice cold seawater above, the minerals in the hot water precipitate and form very fine grained sulphide minerals. These minerals are solidified when cooled down so rapidly and consequently pile up to form the variously shaped chimney-like structures
Life finds its way, even in the most unlikely places
The chimneys spew toxic chemicals in addition to the almost boiling hot water. Thus, one can imagine how inhospitable such an environment is. Nonetheless, a unique ecosystem thrives at hydrothermal vents and is actually driven by chemo synthesising bacteria. These bacteria do not need the sunlight to synthesise organic material, like photosynthesising plants and algae that rely on the sunlight. They utilize the energy from the energy rich compounds found at the hydrothermal vents to create organic material, which other animals can consequently feed off. These heat loving microbes are actually believed to be the oldest life form on earth. They have shown us that life on earth possibly started at hydrothermal vents with chemosynthesis at the bottom of the sea, not with photosynthesis at the water’s surface, as previously believed. Various strange animals have adapted to this harsh environment where they either live in symbiosis with the chemo synthesizing bacteria (where the animal is a host or a shelter for the bacteria and the bacteria synthesizes organic nutrients for the animal) or feed off the thick bacteria mattes found at the chimneys. Many of these strange deep water animals are dependent on the hydrothermal ecosystem and are actually found nowhere else in the world. Examples of these are tube worms, white crabs, octopuses, some fish species, clams and shrimps. Hence, a hydrothermal vents food chain is formed.