We're beginning to learn the rules that govern how everything from flocks of birds to sperm cells flow, and it could transform technology and medicine
By Kate Ravilious
DAVIDE MARENDUZZO watches as the synchronised swimmers rhythmically precess around the edges of the pool. He’s in charge here; he founded this troop and directs their every move. He’ll have them practising like this as long as he likes.
Even though he’s a hard taskmaster, the swimmers aren’t complaining – but then bacteria rarely do. For that’s what Marenduzzo is playing with, and it’s no swimming gala they are competing at. All that training is in aid of a quest to uncover new laws of physics.
Marenduzzo is one of a number of scientists seeking laws that govern fluids teeming with living things. It might be sperm cells on their way to an egg, a fleet of bacteria off to stir up trouble in your guts or a flock of birds heading for their wintering grounds. The idea that these disparate types of flowing life could obey universal laws of nature seems almost untenable. Yet Marenduzzo and others are uncovering some of the first hints that they might.
Turning those hints into a fully fledged theory won’t be easy, but the reward would be amazing. Technologies like self-pumping fluids could be possible and doctors might find they can understand, predict and maybe control the flow of cells – providing a powerful novel approach to medicine.
When it comes to understanding the flow of fluids like air or water, our footing is reasonably solid. The equations of fluid dynamics can predict the flow of gases and liquids