Original Paper

Unusual Pattern of Retinogeniculate Projections in the Controversial Primate Tarsius
Marcello G.P. Rosa^a, John D. Pettigrew^a, Howard M. Cooper<sup>b

a</sup> Vision, Touch and Hearing Research Centre, Department of Physiology and Pharmacology, University of Queensland, Australia;
^b INSERM U371, Bron, France

Address of Corresponding Author

Brain Behav Evol 1996;48:121-129 (DOI: 000113191)

  Key Words

• Primates
• Thalamus
• Lateral geniculate nucleus
• Retinal projections
• Evolution
• Tarsius bancanus

  Abstract

Studies of simian and prosimian primates have demonstrated a remarkable interspecific constancy in the pattern of innervation of the magnocellular and parvocellular layers of the dorsal lateral geniculate nucleus (dLGN) by retinal afferents. The characteristic organization of this nucleus in primates, as well as its apparent phylogenetic stability, have led to the proposal that the distinct laminar arrangement of the dLGN is one of the diagnostic characters that define the Order Primates. Here, we describe the distribution of retinal afferents to the dLGN of Tarsius, the single contemporary member of an ancient lineage of primates. In this genus, the more superficial layer of the dLGN receives projections from the ipsilateral eye, a unique situation among the members of the Order Primates. This observation adds support to the proposal that Tarsius does not share a more recent common ancestry with simians as compared with lemuriform and lorisiform primates.

Copyright © 1996 S. Karger AG, Basel

  Author Contacts

Dr. Marcello G.P. Rosa, Vision, Touch and Hearing Research Centre, Department of Physiology and Pharmacology, University of Queensland, Queensland, QLD 4072 (Australia)

  Article Information

Published online: January 08, 2008
Number of Print Pages : 9