# Confusing predators with reflected or refracted sunlight

Imagine a large butterfly- or moth-like creature, with a wingspan of about one meter (it's moth-like, not actually related to Earth insects). It lives its entire life high in the open sky, never touching (or even approaching) the ground. Additionally, as a consequence of this world's broader cosmology, it is always daytime this far out in open sky, so the moth has nowhere and no time to hide.

There are predators out there, so the moth needs some sort of defense mechanism. Poison might work well, but seems rather boring. Instead, I'd like the moth to take advantage of the ever-present intense sunlight to blind and confuse its would-be predators.

By using its large, (translucent?), finely-scaled wings, the moth can project sunlight via either reflection or refraction precisely into its attacker's eyes, causing disorienting effects that give it time to escape (probably by plummeting straight downwards, which is most species' fastest route of exit in open sky).

At its most basic, the moth would simply blind attackers with highly-focused light. But I'm wondering if more advanced behaviour is able to deal with predators evolving resistant retinas or reflexive third eyelids.

Would it be possible for the moth to be able to manipulate light, either through reflection or refraction, with enough precision to project illusory duplicates of itself into its predators eyes, thus giving them a moment of confusion in which to escape?

At the next level, could the moth project actual holographic duplicates of itself into space, thus creating a 50% chance of predators chasing the duplicates instead?

How realistic is this idea?

As you mention in your question, predators are going to evolve some sort of protection against this prey, if this prey is actually worth hunting. Either extra eyelids or resilient retinas, or motion-sensing-light-patches... or even forgoing eyesight and utilizing another sense altogether.

I would imagine that a world as bright as the one you are describing is likely as inhospitable to eyesight as a completely black cave, and I'd almost expect the most successful hunters to use senses other than sight.

You also have the problem that the focusing materials (in this case, the wings) must be able to survive all the same energy as the target while focusing the light; yes, you have more surface area to spread out the heat, but you're still absorbing a heck of a lot of energy in the process.

Finally, you've got the problem of focus. In order to seriously intensify the light, you've gotta be able to focus that light precisely onto the retinas (or at least faces) of predators. This is a life form which must be ever vigilant and incredibly precise, in order to zap the eyes of hunters stalking it; hunters with bright light adaptations and tons of stealth tricks to avoid being detected by the laser moths.

I think instead of trying to use a focused light beam to disable hunters eyesight, these laser moths would utilize the bright sunlight and their particular situation to dazzle and confuse predators. Give their wings advanced chromatophores; light shines through their wings, gaining color, and then being either transmitted or blocked by the chromatophores. During flight, the chromatophores are pulsed in such a way that the moving patterns on the bottom of the laser moth go in opposite directions of real travel. During stress, the chromatophores can become chaotic and swirling patterns, randomly switching direction of "flow", making it incredibly difficult for predators utilizing eyesight to actually properly predict the direction of travel of the laser moths. Using these chromatophores, they can create optical illusions of direction of travel, speed, and even distance by "fudging" their transmitted image to look smaller than they actually are (imagine a pattern growing smaller on the wings, with the edges of the wings going transparent to show the sky's color through, giving the illusion that it's flying away). Not as cool as projecting holograms, but pretty darned cool.

These laser moths might also have an intuitive sense of heat mirages; they may utilize their pattern projecting ability in addition to mirages, to create "virtual images" which make the laser moth appear to be in a different location altogether. It's not using lensing to manipulate eyesight (which would be difficult, and would require each predator receive a customized modulated image transmitted on their retina) but abusing the mechanics of mirages to enhance their natural cloaking abilities.

Using only reflection and refraction from its wings, such a creature could not create illusory images anywhere but on its body. The reason is that light reflected or refracted from the moth would take the same moth-to-predator path as if the moth were not extra sparkly, so the predator still sees it in the same location.

You might consider though that a highly reflective scaly creature would be very difficult to track in the open sky. Individually, it would be difficult to pin down where the edges and masses of the moth actually were, giving it an advantage when it comes time to dodge as the predator has a hard time seeing what is moth and what is sky. In flocks the problem compounds, and if the scales can be shed as clouds of chaff it gets really visually confusing.

• Countexample: A couple weeks ago I saw an aquarium with curved sides, and the reflection was causing an optical illusion where 3D images appeared in mid air. You can buy toys built on that principle. So, the preditor grabs too close and misses the real prey, even if it is indeed in the line of sight. – JDługosz Apr 23 '17 at 23:51
• @JDługosz the creature can't change its own apparent distance with a curved reflector as you suggest. It could present fleeting reflections of the predator or other nearby objects at various distances, but since the reflecting surfaces are also the flight surfaces, it wouldn't be a persistent illusion and a marginally adapted predator would not be fooled. – Asher Apr 24 '17 at 1:36

Yes.

You can buy toys that make objects appear in the wrong place, and you can try grabbing them and snatch empty air! (I found that link via a Google search for parabolic focus toy illusion.)

A couple weeks ago I saw this occur by accident, due to an aquarium tank window that was not flat. The glare from an outside door's window caused an object to appear in mid air, vivid enough for people to duck around or try to grab once they noticed the illusion.

It's quite possible for the animal's wings to act as a holographic screen, so that somone looking at it will see some projected object in front of the screen, at a closer distance.

• Oh man, I'd loved to have seen a photo or short video clip of the fish tank illusion. – Draco18s no longer trusts SE Apr 24 '17 at 12:43