When I see a dark object on my leg, on my bed, or just on the floor, I immediately assess its symmetry to help deduce whether it is a creature or just a bit of fluff or a fragment of dirt. Symmetry is a pretty sure giveaway indicating life of some sort.
For insects particularly, and some other creatures too, lateral symmetry seems like the kind of thing evolution might have disguised (giving up symmetry altogether is clearly harder than hiding it).
Take the famous peppered moth - why go for all that camouflage and then reduce the effect by carrying a mirror image on each wing? For other prey animals, asymmetrical lumps, bumps or colours can't be out of the question? Are there are examples? Or is symmetry just so useful that lack of it has never been selected?
