The natural history of ticks

Even though they do not fly or jump, ticks have evolved to become one of the most important groups of arthropod vectors of human pathogens. One or more of the approximate 830 known species of ticks are found in most terrestrial regions of the earth. Their life cycles are often complex, and even though we associate ticks with their parasitic habits, ticks live off of hosts; in vegetation or soil, Ticks attach to and feed on mammals, birds, or reptiles. Several species feed on humans, though with one possible exception, humans are always incidental hosts. Ticks have relatively long lives of a year or more and can become abundant in some habitats.