Can birds see blue?

Helen - Well, yes. All you have to really do is look at a peacock's tail to see just how important the colour blue is for birds and in fact, birds have really extraordinary vision because they have four cones. As well as the three that we have as mammals and humans have, they can also see UV and near UV light, and the reason they do this is for all sorts of things. We think it plays a really important role in sexual signals if you cut out the UV part of feathers, it really kind of interferes with how birds can communicate with each other. And it's also quite important for them in their ability to find prey and to forage and find other food. So UV light is very important and they have great colour vision too. So birds are really quite championing the world of colour vision actually, and can see much more than we can.