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The Primordial Soup is a Lie
You've read all about it in your biology textbooks: Life emerged from a stew of methane, ammonia and water that were triggered into becoming the first forms of organic organisms. This theory is being refuted.
J.B.S Haldane, the man behind the primordial soup theory, proposed that UV radiation had been the stimulus for organic compounds to begin fermentation (the process of converting molecules into energy without the use of oxygen). However, this does not include a sustained driving force, and without that, life just cannot exist.
Dr. Nick Lane and others from University College London believe that life came from the bottom of the ocean, near alkaline hydrothermal vents. These hydrothermal vents produce chemical gradients that are very similar to the ones that are found in nearly all living organisms today.
To do work, a cell typically uses a compound called ATP. Think of ATP as a fuel, similar to the kind we put into a car. However, ATP has to be made first, and cells create it by breaking chemical bonds between compounds.
Chemical bonds are broken whenever electrons are transferred -when electrons are transferred or moved, energy is released. However, energy cannot be harvested all at once - it would just get too confusing. Instead, energy is created by transporting an electron down a proton gradient. You can think of a chemical gradient as a series of escalators.
At the start of each escalator, an escort whisks the electron down them- for a price. And the price is 1 or more donations of the cellular currency, ATP.
Sound like a complicated process? Well, it is, and it didn't just sprout up overnight. Fortunately, the natural chemical gradients present in hydrothermal vents could have been exploited by living organisms in a process called chemiosmosis, a way of harvesting compounds or elements in a process similar to osmosis. As cells evolved, they internalized their own chemical gradient, using the same kind of system that had been found in the vents.
"The reason that all organisms are chemiosmotic today is simply that they inherited it from the very time and place that the first cells evolved - and they could not have evolved with it," states William Martin, co-researcher.
Source: Machines Like Us