Two species of micro organism seem to reverse which is predator and which is prey relying on the temperature. Only a small temperature change is sufficient to trigger the change.

The soil micro organism Myxococcus xanthus is a social species that hunts in packs – it types short-term, multicellular “swarms” of people that chemically tear aside and absorb vitamins from different microbes. And its prey contains Pseudomonas fluorescens, a bacterium widespread in each soil and water.…