Plant lice help heal the wounds of their host using their blood, according to scientists at Tsucuba's National Institute of Advanced Industrial Science and Technology. Several species of plant lice create similar grains in plants to live in. Caterpillars pierce the grains and plant lice are unprotected. Therefore, welded plant lice form a crust with their blood to cover the wound. The plant, when receiving the lice signals, takes control of the wound and heals. Researchers expect soldiers' blood to contain new chemical compounds for plant manipulation.