Sibling rivalry takes a grim turn in the parasitoid wasp species Isodontia harmandi, as larvae commonly cannibalize their nest mates. A new study suggests the stronger larvae eat their siblings both to grab an easy meal and to reduce competition for the food provided by their mother. Shown here, an I. harmandi larva feeds on its nest mate. (Photo by Yui Imasaki, Ph.D., and Tomoji Endo, Ph.D., via PLOS ONE, CC-BY 4.0)