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Updated: Jun 23, 2026

The Gateway to the Brain: Dissecting the Primate Eye
Published on: May 27, 2009
Developmental sources of conservation and variation in the evolution of the primate eye
Michael A Dyer1, Rodrigo Martins, Manoel da Silva Filho
1Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA. michael.dyer@stjude.org
Abstract:
Conserved developmental programs, such as the order of neurogenesis in the mammalian eye, suggest the presence of useful features for evolutionary stability and variability. The owl monkey, Aotus azarae, has developed a fully nocturnal retina in recent evolution. Description and quantification of cell cycle kinetics show that embryonic cytogenesis is extended in Aotus compared with the diurnal New World monkey Cebus apella. Combined with the conserved mammalian pattern of retinal cell specification, this single change in retinal progenitor cell proliferation can produce the multiple alterations of the nocturnal retina, including coordinated reduction in cone and ganglion cell numbers, increase in rod and rod bipolar numbers, and potentially loss of the fovea.
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