The little-known creatures called bdelloid rotifers (which means ‘crawling wheel-animals’) live in moss, ponds, and soil. Like other animals, they have a head, mouth, gut, muscles, and nerves - yet they are smaller than a hair’s breadth.
When these rotifers catch an infection, the study found, they switch on hundreds of genes that have been copied into their DNA from bacteria and other microbes. Some of these genes produce antibiotics and other protective chemicals against the disease.
‘When we translated the DNA code to see what the stolen genes were doing, we had a surprise’, said lead study author Dr Chris Wilson from the Department of Biology, University of Oxford. ‘The main genes were instructions for chemicals we didn’t think animals could make — they looked like recipes for antibiotics.’