Biology

How Did Life Arise From Disorder? According To One Physicist, It Had No Other Choice.

What are the chances that of all the planets in all the solar systems in all the galaxies of the universe, ours had the key mix of chemicals and luck to create life? That's a fundamental question at the center of many areas of research. But for physicist Jeremy England, "chance" isn't even an issue. He's proposed that life isn't just a fluke accident amid the chaos of the universe. England believes the chaos of the universe naturally led to the formation of life. His idea, as you might imagine, has its critics.

Entropy Soup

When it comes to physics, the main difference between life and non-life is that life is better at capturing and utilizing energy from its environment. It uses that energy to create and maintain order within itself, then dissipates it as heat. If you're familiar with the second law of thermodynamics, you may be screaming at us to pump the brakes. It states that all the forces in the universe point toward disorganization, not organization. Put another way, chaos (or entropy) only increases; it never decreases. Of course, that's only for so-called "closed systems." If something can take in and expel energy from its environment, the rules change. Still, if everything in the universe is headed toward more and more chaos, how could something as organized as life arise from disorganized atoms?

England is a bit of a physics prodigy who studied at Harvard, Oxford, Stanford, and Princeton before becoming MIT faculty at 29. He crunched the numbers and published a compelling theory in 2013. It says that if a random group of atoms has an external energy source (like the sun) and is surrounded by something that can absorb heat (like the ocean or an atmosphere), those atoms are likely to restructure themselves to harvest increasingly more energy. Structure and the ability to use energy sound intriguingly like what it takes to turn non-life into life, doesn't it?

The Proof Is In The Computing

That's certainly a fun idea. But is it true? Well, in 2017, England put his money where his mouth is by testing the theory in a computer simulation. It started with a hodgepodge of 25 chemicals that react with each other in different ways, some on their own, some with the help of external energy sources. England and his team randomized variables like chemical concentrations, their reaction rates, and rules about how different reactions get an energy boost, then set the models loose to do their reacting.

A lot of the time, the chemicals eased into an equilibrium where the chemicals and their reactions find a happy balance. But not all of the time. Sometimes the chemical systems evolved to a point where they could harvest the maximum possible energy and rapidly burn through chemical reactions, a lot like the cells in our bodies do. It appears that England's theory about the origin of life has legs.

Not everyone thinks this is an airtight idea. Some critique the fact that it doesn't include Darwinian evolution at all, which is a key part of the origin of life. Others say it's a cute physics experiment, but doesn't quite extend into the realm of biology — much less the beginning of life. And others still point to the fact that England didn't use real-world chemicals or energy sources in his model. England hopes to incorporate at least the latter into future studies, but even still, his models are a tantalizing suggestion for how life arose from chaos.

Jeremy England talks about his work on marginally stable proteins

Written by Ashley Hamer August 17, 2017