What is Quantum Biology?

Robin, licensed under creative commons from Ross Elliott — Quantum Biology provides one of the only possible explanations for how birds like the Robin can detect the Earth’s weak magnetic field, using light sensitive proteins in their eyes| Image by Ross Elliott, used under Creative Commons license

Quantum Biology is an area founded on the idea that the weird features unique to quantum mechanics can survive in living creatures, and that they directly affect their function and behaviour. Or, to run that sequence in reverse, systems in nature might have evolved to take advantage of quantum mechanics. Key processes discussed are the efficiency of photosynthesis, and the sensitivity of bird compasses, both of which perform better than expected by classical and semi-classical theories. It’s a big claim, and has faced a lot of rightful skepticism. In this post I’d like to summarise a little about the field, its challenges, and what it can still offer.