You inherited your genes from your parents, half from your father and half from your mother. Almost all other animals contend with the same hand-me-down processes, but not the bdelloid rotifers. This intriguing group of small freshwater creatures are not content with their genetic hand-me-downs; they import genes too. A new study shows that their genomes are rife with legions of foreign DNA, transferred from bacteria, fungi and even plants.

The swapping of genetic material is all part of a day’s activity for bacteria but it’s incredibly rare in animals. But bdelloids are bringing in external genes to an extent that’s completely unheard of in complex organisms. Each rotifer is a genetic mosaic, whose DNA spans almost all the