How did lifeless chemistry begin to edge toward biology? This episode starts with Stanley Miller’s famous attempt to recreate the chemistry of the early Earth, showing that simple gases, water and energy could generate some of life’s basic organic building blocks. But making molecules is not the same as making life. The deeper problem is how random chemistry could become organized without requiring one fantastically improbable stroke of luck. The answer may have been a long sequence of small chemical successes, each preserved and built upon rather than everything appearing at once.

We then follow a possible route: self-sustaining cycles of reactions driven by continual energy, sped up by catalysts, and eventually able to make more of their own components. Once slightly different versions of these chemical networks could arise and some worked better than others, something resembling evolution could begin - even before genes and cells existed. Autocatalysis, in which parts of a chemical network help make more of that same network, provides a tantalizing bridge between ordinary chemistry and the first primitive systems capable of reproducing and evolving.

Molecules Made Me Do It is written and presented by Jeremy Smith.

A popular-science podcast about the beautiful and devious molecules behind life, the mind, sex and the cures of the future. No scientific background required.

Music written and performed by Jeremy Smith.

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