Anatomy of the Nervous of Forearm and Hand of Cebus libidinosus (Rylands, 2000)

Abstract

The knowledge on the macroscopic internal structure of Cebus will provide data for histological and biochemical studies and too will contribute to ethological studies. Behavior, memory, use of tools and encephalization index have put the Cebus genus near to chimpanzees in relation to these aspects. The objective of this study is to characterize the nervous model of the forearm and hand of the Cebus monkey. For this, the main nerves and their branches located in the forearm and hand of the Cebus monkey were anatomically characterized, taking into consideration their frequency, number, origin and distribution. The data were compared with the same nerves found in specialized literature in humans, also specialized in other non-human primates. In this study, 7 Cebus libidinosus monkeys were used. The monkeys were provided by IBAMA (Brazilian Institute for the Environment and Renewable Natural Resources), from the city of Sete Lagoas, State of Minas Gerais, in 1970, and housed at the anatomy collection of the Goi�s Federal University (UFG). For the nerves of the forearm of Cebus, no variations were observed in the innervation pattern of the muscles, except for the deep flexor muscle of the fingers, which in Cebus and baboons is innervated by the ulnar nerve and in humans and chimpanzees by the median nerve; however, these nerves exchange fibers in the arm and in the brachial plexus. Innervation variations may occur in the fingers of Cebus in relation to other primates, but these variations have been reported with variations in humans. This identical innervation pattern in relation to the nerves of the arm and forearm and hand in Cebus justify its use as model for anthropological evolutionary studies.(AU)^ien