Arboreal locomotion small branches, as they may wrap too far around and prick the animal's own paw. Adhesion is an alternative to claws, which works best on smooth surfaces. Wet adhesion is common in tree frogs and arboreal salamanders, and functions either by suction or by capillary adhesion. Dry adhesion is best typified by the specialized toes of geckos, which use van der Waals forces to adhere to many substrates, even glass. Frictional gripping is used by primates, relying upon hairless fingertips. Squeezing the branch between the fingertips generates a frictional force that holds the animal's hand to the branch. However, this
Arboreal locomotion through. These obstructions may impede locomotion, or may be used as additional contact points to enhance it. While obstructions tend to impede limbed animals, they benefit snakes by providing anchor points. Arboreal organisms display many specializations for dealing with the mechanical challenges of moving through their habitats. Arboreal animals frequently have elongated limbs that help them cross gaps, reach fruit or other resources, test the firmness of support ahead, and in some cases, to brachiate. However, some species of lizard have reduced limb size that helps them avoid limb movement being obstructed by impinging branches. Many arboreal species, such as