Alex McColgan

Despite creating extremely localized order, life degrades free energy to heat, increasing entropy in the universe overall.

Unsurprisingly, given that you're watching this video, it's clear that entropy allows for, or even encourages, the development of life.

So how did the building blocks of life seemingly defy entropy in constructing order from chaos?

How does a living cell build up that can power itself, encode itself with DNA, construct itself too, and have the ability to evolve?

And how can it do it all piece by piece while being functional at every step, even though each part is essential?

How on Earth could life emerge?

Well, there is little consensus on the precise way that life actually emerged on Earth, but let's explore the molecules that, without exception, build every single life form on Earth.

Perhaps life offers clues to its own origin.

The key basic building blocks life uses today in no particular order are fatty acids, amino acids, and nucleotides, and all three are believed to have been present on the early Earth, and have even been found on asteroids in our solar system.

The first are fatty acids, and despite having little chemical functionality, they create structure and have an extraordinary function built in.

These long chain molecules make up cell walls of all life on Earth and are believed to have made the first membranes of protocells.

Membranes are barriers and fundamental to create an individual unit.

After all, you can't have a house without walls or a country without borders.

That's not a political statement.

Remarkably, cell-like structures made from fatty acids form spontaneously in water.

As anyone who's failed to make simple mayonnaise will know all too well, oil and water don't like to mix.

These fatty acids, with a water-loving head and a water-hating tail,

will spontaneously arrange to minimize water's contact with the tail and maximize it with the head.

These simple pressures can create a bilayer membrane with a cavity for an early cell to call home.

This is called a liposome.