Fascinating fact
August 29th, 2010
Birds see ultraviolet.
They have four cones. While we have red, green, and blue cones that respond
(respectively) to long-wave, medium-wave, and short-wave light, birds have all
those plus a fourth cone that responds to very-short-wave light--ultraviolet
light. Essentially, birds have four primary colors to our three. (So do many
fish, reptiles and insects.) They see not only UV itself, but various
secondary colors that come from the combination of UV with red, green, or
blue. None of this is conceivable to a mammal. Even if we could give a human
being UV cones, they still wouldn't see the world the way birds do, because
their brains aren't set up to process the fourth input.
The
Yellow-Breasted
Chat, for instance--an oversized warbler found in the states and far-south
Ontario--has a breast which reflects both yellow light and UV light. Thus,
when Yellow-Breasted Chats look at each other, they don't see yellow breasts.
They see a bright color that is completely beyond our experience or
conception.
- Paraphrased from
National Geographic Bird Coloration