There are various ideas existing today suggesting how life first emerged on the planet. They range from the scienfific to the theological to the fantastical. Some of these ideas claim that an inteligent force, a god, alien or otherwise, created Earth’s life. Others claim that the first organisms arrived on earth from outer space. The most commonly accepted theory today is that life first evolved on this planet around hydrothermal vents like those seen above.
The reason we think life first emerged in these environments is due to their chemical composision and location. They are deep enough in the ocean to avoid the deadly rays of the sun and contain all the chemicals necessary for the development of very simple organisms. There is a very compelling line of evidence suggesting that all modern life evolved from organismed that lived around these vents. All life existing today shares DNA that suggests a common ancestor that would like a hot environment contianing the compounds found around hydrothermal vents.
So why is the emergence of life owed to tectonic activity? This is because these thermal vents are formed through the movement of the Earth’s crust. As two oceanic plates move away from eachother fissures open up in the ocean floor. These fissures suck in cold sea water, heating the water and mixing it with these compounts that could support early life. This hot compound rich water is then ejected in thick cloudy plumes.
Weather the first organisms on earth evolved from naturaly occuring organic compounts or our ancestors arrived on meteroites it is clear they lived around these vents. Our existence is owed to the processes that form these vents, plate tectonic activity.
Life and Geology 