Julid Millipedes include about 750 species which inhabit North America, Europe and Asia. They range in size from 1/3 of an inch to up to almost 5 inches long and their bodies have more than 20 segments with 2 pairs of legs on each segment. Millipedes originated about 1.5 million years ago and are some of the oldest known land animals. They are found living under bark, logs, rocks and leaves and consume decayed vegetation and vegetable matter such as roots. Millipedes are not harmful to humans but can be destructive to gardens. They are slow moving, do not bite and coil into a ball when threatened. Some species emit a foul-smelling liquid to deter predators. Their secretions can cause skin irritations to humans. Millipedes are used in parts of Africa and the Himalayans as medicine to treat fevers, and wounds. Millipede activity is also known to be a sign of weather changes and coming rains.