Narrator: This is Science Today. There's a large industry involved in making reflective paints and even computer graphics with very reflective surfaces, in part because people seem to respond to shiny surfaces. Richard Coss, a professor of psychology at the University of California, Davis decided to look into this phenomenon.
Coss: Some of the oldest art work involves polishing stone tools and so this is something that led to thinking there might be something very basic – perhaps a natural property of our species.
Narrator: Coss studied infants and toddlers' responses to shiny surfaces after observing them placing their heads on mirrors and other shiny surfaces and making sucking motions with their mouths as if drinking water.
Coss: The source for this attraction looks like it's involving detecting glistening surfaces at a distance – probably sparkling effects of water. You know ancestral humans and even going back further, once there were conditions where we were living in environments that were drier – we required a drink every day. So that was sort of the fundamental point about looking at it from an evolutionary perspective.
Narrator: For Science Today, I'm Larissa Branin.