Arboreal locomotion a synapsid of the late Permian, about 260 million years ago. Some animals are exclusively arboreal in habitat, such as the tree snail. Arboreal habitats pose numerous mechanical challenges to animals moving in them, which have been solved in diverse ways. These challenges include moving on narrow branches, moving up and down inclines, balancing, crossing gaps, and dealing with obstructions. Moving along a narrow surface poses special difficulties to animals. During locomotion on the ground, the location of the center of mass may swing from side to side, but during arboreal locomotion, this would result in the center of mass
Lost Animals of the 20th Century such is unavailable, the live materials feature existing species that share the closest characteristics with the extinct animal. Although the show specifically deals with animals that have become extinct, there was one episode that featured the theme of animals which were thought to be extinct, but have been rediscovered. Such has also been the case of some previously featured animals in the show, as scientists have eventually rediscovered extant populations or are attempting to revive species through selective breeding/cloning. Among the animals featured are: Lost Animals of the 20th Century Lost Animals of the 20th Century is a 16-episode documentary