ABSTRACT
The family Tupaiidae ranges from India and southern China throughout most of southeastern Asia. Despite taxonomic ambiguities and the apparent remoteness of a tupaiid-primate relationship, there are several reasons why tree shrews merit inclusion among studies of primate locomotion. Dental similarity between tupaiids, marsupials, and insectivores makes it unlikely that an early Tertiary fossil tupaiid will be positively identified without the recovery of more of a skull than the dentition. From the zoological descriptions tupaiids have been associated with a squirrel-like habitus in name as well as description. Squirrel-sized or smaller, tree shrews are represented by five genera (Anathema, Dendrogale, Ptilocercus, Tupaia, and Urogale). The locomotor repertoire of tree shrews is adapted to two major topographical features of their habitat. The first is that most surfaces, in terms of the actual plantar area of tree shrew feet, are not level. A second feature of the forest habitat is the disordered spatial arrangement of locomotor surfaces.
