All life, humans, plants, animals and fish, probably evolved from a primitive slime growing in utter darkness at the bottom of the Earth's oceans, and the process which originated life is most likely still under way.
Scientists have discovered a new "hot smoker" on the seabed of the North Atlantic, a vent along the mid-ocean ridge where the Earth's crust is pulling apart exposing its molten mantel.
These vents belch out gases, chemicals and heat, and many have been found since the first was discovered 20 years ago, explained Joe Cann, professor of Earth sciences at the University of Leeds.
This one is very different, however, and has the scientists who study the complex chemistry and microbial colonies which thrive at the vents very excited.
It emits large amounts of hydrogen gas, thought to have been essential for the building and replication of the amino acid precursors of life as we have come to know it.
The black smokers are oases in the deep ocean where no light can penetrate, but where microbial life can flourish. The society of organisms which live there rivalled the complexity and variety of the tropical rain forests, Prof Cann said. Evidence of the Earth's earliest microbes dates back 3.86 billion years, but scientists have wondered how they could have originated and then grown in the near absence of free oxygen.
"They must have worked using hydrogen," Prof Cann suggested, also using carbon dioxide and what we know as rust "to kick start life".
Most vents emit large amounts of hydrogen sulphide and a little free hydrogen, but the chemical energy from hydrogen sulphide would not have been enough to allow replicating amino acids and ultimately life.
The new vent, discovered last summer in a 200-metre diameter area called the Rainbow Field in the North Atlantic, gives off 15 times the usual amount of hydrogen and this gas "just about gives enough energy for life to start", Prof Cann said. It is given off when a silicate mineral called peridotite reacts with sea water deep under the seabed.
"The key to life as I see it is a planet with liquid water, volcanoes, peridotite to give off hydrogen, and when you have those things all coming together you can have life. We suspected hydrogen for the origins of life and we now have a place in the modern world where life could originate and perhaps is originating now," he said.
The chemical transformation towards life occurred when complex organic chemicals brewing billions of years ago around the Earth's original vents reacted together in the presence of a catalyst such as rust. Sometimes the organic slime catalysed slowly, but other organic combinations would have reacted more quickly.
These faster chemicals would proliferate, repeating themselves but also recombining with accidental errors that might have introduced still faster catalytic reactions.
Scientists believe this is the stuff from which life eventually emerged. If new forms and combinations were forming now around the Rainbow Field vent then they would be gobbled up quickly by the hungry microbes already living there today, Prof Cann suggested.
Dr Chris German, of the Southampton Oceanography Centre discovered both high temperatures and unexpected particles on the surface above the vent and tracked its plume down to the mid-Atlantic ridge.
A French researcher, Dr JeanLuc Charlou, of Ifremer, in Brest, then used a submersible to dive down and actually pinpoint the hydrogen vent.
It lies under 3.5km of water with temperatures next to the vent reaching 362 C. The nearby microbes survive temperatures of about 110 C.