Sensing Colour in Nature

Robert DeSalle
American Museum of Natural History

Abstract
All living organisms are swimming in a world of information made up of small molecules, sound waves, gravity and most importantly for this talk, light waves. Many of these organisms on our planet have figured out how to use light in a wide range of ways. And of course “figured out” is just shorthand for “evolved”. The broad range of uses for light by organisms on this planet has probably evolved due to the plethora of different wavelengths of light hitting our planet. And there are a bonanza of things on our planet for the light to bounce off, or to be absorbed by. Most organisms use light to inform them of their surroundings, but some organisms use it as food for energy. Some organisms on our planet have learned to “sense” color without eyes, and even without brains. The perception of light in non-seeing, eye-lacking organisms starts the same way as we humans perceive colors – with light waves hitting cell surfaces followed by a cascade of inter and intra-cellular reactions. Organisms have evolved more complex perception of light and the ability to perceive different wavelengths of light as a way to stretch their utility of light wave information. To better understand the role of color in nature, we will delve into the biochemical and neurobiological levels of light and light detection in organisms, how color in nature is used by organisms to expand the information they receive from their surroundings and how organisms on our planet diversified as a function of color. This last goal is all about evolution. Color is a major factor in much of the adaptive change we see in organisms around us. Adaptation and natural selection have shaped the way color is distributed on our planet and is very tightly interlaced with our human impression of our colorful planet. Understanding the evolution of color and its place in nature is the first step to understanding the perception of color.

Bio: Rob is a curator at the American Museum of Natural History working in comparative genomics. He is also a professor in the museum’s graduate school, The Richard Gilder Graduate School, and has been adjunct professor at New York University, Columbia University, City University of New York and Yale University. He recently received a Fulbright Professorship to work in Australia and a von Humboldt Fellowship for work in Germany. His scientific work at the museum is complemented by exhibition outreach for which he has curated a permanent hall on Human Evolution and seven temporary exhibitions including Brain: The Inside Story , Our Senses and currently The Nature of Color He has written over twenty books including Our Senses (Yale Press), Troublesome Inheritance (Columbia University Press) and A Natural History of Color. (Pegasus Books). He lives in the East Village of New York City with his wife and son.