The insect is a parasitoid wasp, Venturia canescens. Parasitoids were the inspiration for the Alien series of films – they lay their eggs inside the bodies of other insects, where they hatch and devour their hosts alive from the inside. This species has been used as a natural pesticide to control the Indian meal moth, Plodia interpunctella, which is a pest of stored grain and flour. 

The coloured shapes illustrate my experimental and mathematical exploration of populations of Venturia and its host. Parasitised hosts are weaker and can't survive when competing in high density host populations. This may make Venturia a less effective pesticide for controlling Plodia than might be expected.