A method of dispersal in which an animal attaches itself to an animal of another species in order to be transported to a new site, where it releases itself, with little or no harm to the carrier. This method is adopted by various animals searching for new food sources, or by parasites when seeking a new host. For example, when their host dies, certain bird lice may attach themselves to blood-sucking flies in their effort to find a new avian host, and some insect parasitoids, which lay their eggs inside the eggs of other insects, attach themselves to adults of the host species to ensure immediate access to the eggs when the adult host lays them. Eggs may also be transferred in this manner. The Neotropical human bot fly, Dermatobia hominis, ‘captures’ a suitable carrier, such as a blood-sucking mosquito, to which it attaches 30 or so of its eggs. When the carrier insect reaches a human or bovine host, the bot fly eggs quickly hatch and the larvae release themselves from the carrier and invade the hair follicles of their host, where they develop.