• Question: Why do animals and humans see differently, does anyone have the correct vision or does the vision exist at all? Is it our illusion?

    Asked by George to Carrie, Cedric, Ellen, Ines, Rupert on 10 Mar 2017. This question was also asked by Julen.
    • Photo: Carrie Ijichi

      Carrie Ijichi answered on 10 Mar 2017:

      We have different densities of special cells in our eyes. Some are really good at picking up light so you can see in the dark, others detect colour. We’re great at seeing colour but not so good at night, other animals need to see at night but they loose the ability to see colour the same way. Also, some animals can see with more or less precision than we can – so a bird of prey has incredible eyesight to see prey from great heights but a mole that lives underground in the dark doesn’t see well. It all depends on what they need to survive in their environment. Hope that helps!

    • Photo: Rupert Marshall

      Rupert Marshall answered on 10 Mar 2017:

      That’s a great question! In terms of colours, no animal sees all colours perfectly. Even animals which can see lots of colours are better at seeing some than others – they have peaks of sensitivity. For most animals, Einstein was right: everything is relative….to what their eyes can actually see. If you watch an old black and white TV you can still see the picture. The reds and blues aren’t there but the shapes can still be seen as shades of grey. Humans can’t see ultraviolet, but birds can – blue tits have bright ultra violet heads, but we only see the blue.

    • Photo: Ellen Williams

      Ellen Williams answered on 10 Mar 2017:

      Fantastic question! As both Carrie and Rupert have pointed out below all animals have different levels of vision and it is all designed to be optimum for their needs. I often wonder though how do we ever know what other animals see when we don’t even know what each other sees? For example we know that we might all describe the same colour as ‘red’ but no-one knows what another persons red actually is! It is food for thought! The universe is a weird and wonderful place!

    • Photo: Ines Goncalves

      Ines Goncalves answered on 11 Mar 2017:

      I don’t think you should separate us between “humans” and “animals” because so many species see differently, it’s not like all “animals” see the same way and then we “humans” are different. We have all evolved visual systems that broadly speaking work for our purposes. This doesn’t means it’s the best ever system or that there is one best system, because evolution also has its limitations, but it does means that we are adapted to the environments we experience. As a rule of thumb, think that all species do the best they can given what they have, i.e., you can’t make a porkpie with a lamb, but you can make pretty good lamb chops. Similarly, if Ferrari’s were considered the best car in the world in terms of everything: looks, speed, comfort, etc, not everyone would have a Ferrari. At the basic level, a Ferrari doesn’t take you further, it doesn’t last longer or provide any essential benefits that other cars don’t provide, and in the vast majority of circumstances you don’t need to travel 200km in 30 minutes. Ferrari’s are, however, much more expensive to maintain. So if you think of visual systems, you could have all the different types of cells that currently exist, in all possible different arrangements that would enable you to see all colours, UV as well as infrared and you’d be able to see polarisation and all other properties of light, but such a visual system would be too expensive to maintain in terms of energy. And would you need such a system?

    • Photo: Cedric Tan

      Cedric Tan answered on 12 Mar 2017:

      Interesting philosophical question! Animals and us see different because of many reasons. Cats that hunt at night have great night vision like that of night vision goggles, some birds can see uv because there are uv colours on their mates that show how attractive they are!

      I wouldn’t say that anyone has a correct vision. It’s difficult to see the world through someone else’s eyes. Movies like the matrix and surrogate are interesting because they represent an idea when we are merely seeing an illusion. Perhaps the answer is not far given that virtual reality is now a reality!

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