Hindsight Wasn't 20/20 Nor As Colorful: The Evolution of Primate Vision

Sunday, February 19, 2017: 3:00 PM-4:30 PM
Room 210 (Hynes Convention Center)
Amanda Melin, University of Calgary, Calgary, AB, Canada
As humans, most of us see our world in vivid colors and fine detail, but the genes that encode these traits vary widely, and colorblindness is a common anomaly of our species. These aspects of our visual system distinguish us from all other mammals, but how and for what purposes did our visual system evolve, and what does the future hold for the visual ecology of our species and other primates? Melin uses diverse techniques in areas ranging from genetics to primate behavior to computer simulations to infer the color vision and acuity of our ancestors. In doing so she unravels a sequence of key innovations that occurred during the evolution of the primate visual system. By analyzing the genes underlying color vision in primates, their close relatives the treeshrews and colugos, and a diverse sample of other mammals, Melin predicts the form and sensitivity of color vision in our early ancestors and demonstrates current uses of color vision. Her analyses reveal: 1) a shift from UV vision towards blue sensitivity, underlying an early increase in visual acuity prior the divergence of primates and treeshrews; 2) that the color vision variation leading to mixed populations of “colorblind” and “color-normal” is a uniquely primate condition that arose along with further increases in acuity in our lineage. By studying primate behavior and using computer simulations of visual systems, she demonstrates; 3) that primates in the wild use red-green color vision to eat fruits more quickly and also to better see nutritious leaves; 4) that colorblind monkeys can break camouflage to find disguised insects, and that colorblindness may also have been adaptive in our Homo lineage. To conclude, she discusses possible impacts that anthropogenic disturbance of the environment might have on the color vision and activity patterns of our own species and other primates, many of which that are critically endangered. In sum, by using diverse techniques Melin pieces together the evolution of vision in our lineage, and simulates what the world might have looked like to our ancestors and may look like in the future.