ABSTRACT
This chapter describes a uniquely modified type of wrist joint is shared by the Pongidae and Hominidae but is quite unlike the monkey type of morphology suggested for Dryopithecus africanus. The elaboration of the evolutionary novelty can be shown to have played a key role in the evolution of the hominoid wrist. The hominoid wrist joint changes seem to present an evolutionary breakthrough of comparable magnitude. The Human Wrist Joint is obvious phylogenetic significance to consider whether Homo has shared similar wrist joint modifications with the Pongidae. The most aberrant derivative of the basic hominoid pattern is seen in Pongo. No facet for the meniscus is found in Pongo and Homo, but during human fetal development the pisiform is more proximally located and largely articulates with the periphery of the meniscus. The characteristic hominoid angulation and migration of the pisiform distally into the palm is in strong contrast to its disposition in monkeys.
