Visual ecology is the study of how visual systems function to meet the ecological needs of animals, how they evolved for proper function, and how they are specialized for and involved in particular visual tasks. For example, prey species need to be able to detect and avoid their predators. Many herbivore prey species, including deer, possess laterally positioned eyes and horizontal pupils that facilitate a near panoramic field of view. This wide perceptual field helps deer and other prey species detect and avoid their predators. Understanding the perceptual space of deer aids us in interpreting their decision-making processes and behaviors and understanding their visual ecology.
The perceptual space of a deer is determined by the world it perceives through its various sensory systems (e.g., olfaction, chemo-sensation, vision, etc.). The visual information available to a deer is constrained by the physiological properties of its sensory system and the physical characteristics of its environment. For example, the orange-yellow fur of a tiger contrasts sharply against a predominantly green backdrop for a trichromatic human while a dichromatic deer would perceive a minimal contrast in color between the tiger’s fur and the green backdrop. The high color contrast humans experience in the described scenario is a result of the physiological properties of our sensory system and possession of both M- and L-cone photoreceptors (i.e., green and red photoreceptors). In contrast, dichromats often have either an M- or L-cone photoreceptor, not both, and perceive less contrast between green and red colors relative to trichromats. It is unclear if dichromatic vision helps or hinders deer in predator detection and avoidance given predation risk from cryptic species like tigers and jaguars. However, these types of scenarios and questions can only be answered with a better understanding of deer visual ecology.
To better understand deer visual perception and ecology, doctoral student Blaise Newman and Dr. D’Angelo of the UGA Deer Lab are collaborating with researchers in the Department of Cellular Biology and the Behavioral and Brain Sciences Program in the Department of Psychology. Funding for this project was provided by SITKA® Gear in an effort to advance the knowledge base of deer visual systems.
Areas of research interest include:
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Assessment of the contrast sensitivity (i.e., ability to distinguish an object from its background) and temporal contrast sensitivity (i.e., contrast sensitivity as a function of time) of white-tailed deer.
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Influence of light environments on white-tailed deer movement and resource selection.
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Variation in deer tapetum reflectance across multiple latitudes and habitats.