The most common centipedes found around structures are fast-running predators of other arthropods, such as insects, as well as earthworms and snails. They generally are nocturnal, hiding under boards, rocks, or vegetation on the soil during the daytime, and seen only when they are disturbed and uncovered. Centipedes do have the ability to inject venom through the pair of appendages directly behind the head, called maxillipeds. The North American species are relatively harmless to humans, while species in tropical Latin America may cause a serious reaction. At least one large western species also can cause severe pain with its bite. Some species may live up to 6 years. Females lay their eggs one at a time, usually burying it under a shallow layer of soil to protect it from being eaten, possibly even by the males.