The first episode of Molecules Made Me Do It begins, naturally enough, with sex — or more precisely, “aquasex.” An ancient Mesopotamian creation story imagined life beginning with the fertile mingling of fresh and salt waters, personified by the gods Apsu and Tiamat. Surprisingly, this provides a useful jumping-off point for asking what modern science thinks life actually is. We explore definitions from Jacques Monod and NASA, meet Darwinian evolution, and ask what distinguishes a living chemical system from things such as flames and crystals that display some lifelike properties. PODCAST 1 PODCAST 1

We then travel back to the violent young Earth and its hypothetical primordial soup. Why wouldn't a mixture of the right chemicals simply turn into life if we waited long enough? The answer leads us into thermodynamics, entropy and the Second Law — and the loophole that allows life to create local order without breaking any laws of physics. The missing ingredient is a sustained supply of usable energy, perhaps from sunlight, electrical discharges or hydrothermal vents. Finally we return to Apsu and Tiamat and discover an amusing parallel: mixture plus generative energy producing something entirely new — what modern science would call an emergent phenomenon. PODCAST 1 PODCAST 1PODCAST 1

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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