They are slower than centipedes, and feed on leaf litter and detritus. Around 8,000 species have been described, which may represent less than a tenth of the true global millipede diversity. One species, "Illacme plenipes" has the greatest number of legs of any animal, with 750. Millipedes typically have between 36 and 400 legs. Pill millipedes are much shorter, and are capable of rolling up into a ball, like pillbugs.