The emerging picture of microbes as gene-swapping collectives demands a revision of such concepts as organism, species and evolution itself.

In a trail-blazing experiment 50 years ago, it was observed that photons from far-off stars bunch up. But in fact there's a more general distinction among free, non-interacting particles: bosons bunch, and fermions 'antibunch'.

Modifier proteins, such as ubiquitin, are passed sequentially between trios of enzymes, like batons in a relay race. Crystal structures suggest the mechanism of transfer between the first two enzymes.