Many species are omnivorous, eating primarily small insects and all kinds of plant material and fungi. Some are scavengers, feeding upon dead organisms, bird dung, and other fecal material. Such a broad range is unusual in arachnids, which are typically pure predators. Most hunting harvestmen ambush their prey, although active hunting is also found. Because their eyes cannot form images, they use their second pair of legs as antennae to explore their environment. Unlike most other arachnids, harvestmen do not have a sucking stomach or a filtering mechanism. Rather, they ingest small particles of their food