Question: Life. Inevitable, or just a fluke?

James Verdon answered on 1 Jul 2012:

That’s a really good question megaehb!
Obviously, life seems pretty inevitable to us, because our planet is so full of it. But then you look into space at other planets and we’ve not found one with life yet.

Some experiments in the early 1950s by a scientist called Urey are really interesting in this respect. He put a load of chemicals into a jar – water (H2O), methane (CH4), ammonia (NH3), and hydrogen (H2). These are all natural chemicals that could easily have been present in the atmosphere of earth right at the beginning, before life began. He passed electric currents through the mixture – not that different to lightning striking really. He found that the mixtures reacted to produce organic chemicals like amino-acids, which are necessary to form the building blocks of life.

This was only a small experiment, but it showed that to create the complex organic chemicals needed for life, all you needed were the simple, commonly occurring inorganic chemicals, and an electric current. So it has been a very influential experiment.

So to answer your question, it seems like life is inevitable, but only with the right starting conditions. Most planets don’t have these conditions, so life doesn’t get going. Earth did, so we developed life. Maybe one day we’ll find another suitable planet and we can see if life developed there as well – so far we’ve not found one.