Re: Trace of lifeforms 3.7 bln years old
There is commonality between Earth in that geological age and now, at the hydrothermal vents. The environment there is pretty much identical to what it was four billion years ago. Same chemical makeup, same lack of light, and same absence of oxygen in the water.
And finding this is not the same as finding it on Mars around the same time period, because that would prove that either 1) life was not a crazy accident so it is very likely in all Earth-like planets or 2) that both were 'seeded' from the same extrasolar source since there wasn't time for life to travel on a meteor from one to the other so soon after the crust was formed. Either would have far bigger implications than this discovery alone.