In 1986, Craig Reynolds was thinking about birds. Many bird species, famously starlings, form swarm-like groups – murmurations – that have remarkable cohesion and move with what looks from the outside like singular purpose. Biologists were still struggling to explain the phenomenon. Some thought there might be a ‘leader’ bird, which humans couldn’t pick out, but which was obvious to its flockmates.
Reynolds is an animator and programmer, not a biologist, but