Animal locomotion many of these same principles may be applied to climbing without trees, such as on rock piles or mountains. The earliest known tetrapod with specializations that adapted it for climbing trees, was "Suminia", a synapsid of the late Permian, about 260 million years ago. Some invertebrate animals are exclusively arboreal in habitat, for example, the tree snail. "Brachiation" (from "brachium", Latin for "arm"), is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms. During brachiation, the body is alternately supported under each forelimb. This is the primary means of locomotion
Vicente Pérez Rosales National Park reeds. A diversity of animals of the rodent group live in the park. The larger ones are coipo, coypu, "Myocastor coypus", a webbed-feet animal that inhabits reedy lake and river banks; and Wolffsohn's viscacha, "Lagidium wolffsohni", of the family Chinchillidae, whose preferred habitat is above the timber line. Among the smaller rodents, scientists have shown particular interest for Chilean climbing mouse, "Irenomys tarsalis", and for the long-clawed mole mouse, "Geoxus valdivianus". The park is home to two species of marsupial mammals. Monito del monte, "Dromiciops gliroides", has a semi-arboreal habit. It has been discussed why this South American marsupial appears