Bloodsuckers are organisms that feed on the blood of other organisms. Fleas, ticks, leeches, lice, bedbugs, and parasites are all examples of bloodsuckers. Fleas are small, wingless insects that feed on the blood of mammals and birds. Ticks are small arachnids that feed on the blood of mammals, birds, and sometimes reptiles. Leeches are segmented worms that feed on the blood of vertebrates. Lice are small insects that feed on the blood of mammals and birds. Bedbugs are small, wingless insects that feed on the blood of humans and other warm-blooded animals. Parasites are organisms that live in or on another organism and feed off of it.