Question: Is it true that dogs see in black and white?

Sam Geen answered on 24 Jun 2013:

Yes! Certain animals don’t have the cones in their eyes that allow them to see colour as we do. Rods are more sensitive to light, but only see one frequency range of light rather than three, so can only pick up shades of light and dark. Bulls also don’t see colour – a red rag annoys a bull because it’s moving, not because it’s red. Ducks, on the other hand, have 4 sets of cones, meaning they can see four colours, and hummingbirds can even see in ultra-violet.

EDIT: My awesome sister corrected me! She studied psychology and is currently writing a novel about people jumping into the minds of animals, so she’s studied this a lot. She says:

Dogs see in the yellow/blue spectrum. Seals have green cones so they’re monochromatic (as are most ceatceans [like dolphins, porpoises, whales] & pinnipeds [like seals, sealions]). Apparently skates are the only animal that are confirmed to have no cones at all, hence true b&w vision: http://www.pattyvisioncenters.com/index.php/myth_busters/myth/animals_only_see_black_and_white

So there you go! Sometimes it’s a good idea not to trust an astrophysicist talking about biology…