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Anyone into digital photography knows that sometimes the photos turn out with colours that are not, actually, the ones you saw at the time you took the picture. Although digital cameras got better in rendering colours there are still quite a few situations where they get distorted. Few aficionados know that they need to tinker with the camera white balance to have the colours rendered in a correct way and they also know that this is not easy at all.
To render the colours of a scene in a faithful way the camera makes the assumption that our world is, on average, grey! Based on that it automatically sets the white balance to get an average grey. Of course there are plenty of situations where this assumption is false, think about a sunset where actually the average is leaning to the orange-red…
A bee is facing the same problem, although for a bee it is a matter of life or dead to be able to recognise a flower in different light conditions, to get the right pollen. And bees have evolved a brain that, although very tiny, is quite smart in compensating from different lighting condition to get the real colour (real from a bee point of view that in practice seems to be shifted towards the ultraviolet… see the clip to … see like a bee – or a butterfly!).
Researchers at RMIT in Australia have studied bees and discovered the role played by their 3 ocelli (little sticks on the front of their head) in getting the colour right, compensating for the lighting situation.
Differently from what our brain does, our brain is also smart and compensate for lightning situations but only to a certain point, since in our case the issue is not to get the “true” colour (whatever true can mean in this context!) of an object but to get a meaningful image (as an example we see wonderful reddish sunset, which makes sense to use because sunsets are reddish, aren’t they? Well actually not, it is just the effect of changing lighting with a red dominance), a brain bee needs to identify a specific flower hence it has to get rid of any lightning dominance. The ocelli provides information on the light dominance (from above, from the sky, bees did not evolve in cities lightning, they are not expecting neon lights and indeed they would get confused by them!) and this information is processed by the bee brain to identify a flower (it is likely, as shown in the clip that bees are looking for patterns generated by colours rather than from colour itself).
The research points to a way to detect true colours with very limited processing power. This can be used by digital cameras, robotic vision and self driving cars. Nature has found very inexpensive ways to solve problems and there is plenty for us to learn and exploit!
