The 6 Most Mind-Blowing Animal Senses

#3. A Spookfish Can Hunt and Keep a Lookout Simultaneously, With Mirrorvision


This slimy deep sea horror is called a spookfish, because in the world of biology it's considered unprofessional to call something "orange nuts boner face."
"Oh, come on! I know I've suggested it hundreds of times, but this time it actually fits."

If you had to guess which parts of that nightmare are its eyes (like if you needed to know where to aim if you were facing a giant one in a video game boss fight), you'd go for those big orange spheres. But the reality is much cooler than that.

You see, fish that live in the endless night of the briny depths face a problem shared by fat kids who get bullied in middle school: They have to look for food while staying alert against their own predators. You almost need eyes in the back of your head ... or the ability to look up and down at the same time. This fish does that, with internal mirrors.
He's a tiny swimming disco.

The spookfish has split eyes, so it can see in both directions at once -- it's literally like having eyes in the back of its head. It's actually not a separate pair of eyes, but a complicated system that uses a curved mirror of reflective plates to collect the miniscule bits of light to be found a half-mile under the surface. So it's less like having eyes in the back of your head and more like having a pair of those novelty sunglasses with mirrors that let you see behind you. It is the only vertebrate creature on earth that does this.

It makes a little more sense looking at it from the side:
So really, The Simpsons wasn't that far off.

The eyes are going the opposite direction you think -- the little black eyes on the bottom are looking up, for food. The big "eyes" on top are actually the backs of this mirrored surface, which collect little flashes of bioluminescence below that signal a predator is coming (the spookfish is vulnerable from below, something else useful to know if you ever have to fight a giant one).

By the way, if you're wondering why animals vulnerable to attack from above haven't also evolved some kind of upward-looking eye just to keep watch out for them, well, they have. Go grab a lizard out of your yard. See that dot in the middle of its forehead?

Bill Peterman
It's right next to the naturally occurring arrow that floats over its head to ward away predators.

That's called a parietal eye. It's a light-sensitive third eye that lots of creatures have, specifically to act as an anti-aircraft radar that detects aerial predators.

#2. The Mollusk With Eyes Made of Rock

The West Indian fuzzy chiton may not look like much. In fact, as a 3-inch-long mollusk sitting at the bottom of the Atlantic Ocean, you probably don't notice it at all. But if you happen to be swimming above the thing, it notices you ... with eyeballs that are made of rock. And we don't mean they look like rocks, or have a rocklike texture. The chiton's eyes are made of aragonite, or a form of limestone, the same material that makes their actual shells. But instead of being strictly rock and more rock, the eyes have evolved "a layer of pigment, a retina and a lens."

Discover Magazine
Phew, we thought those were chiterpes.

In other words, these small sea golems have figured out a way to see the world with the same material we use to construct buildings and roads. They don't see well, mind you, but it's enough to clamp down like a mofo when a predator comes swimming by.

Oh, and by the way: Their eyes will dissolve if you try to clean the chiton in anything mildly acidic. Because their eyes are made of limestone.
"I dunno, man, I just dropped acid in my eye, and the whole world turned beautiful."

#1. Dolphins Use Holographic Imaging to See Inside You

Everyone loves dolphins. They're playful, lovable and intelligent, and they rarely ever kill just for the fun of it. But when they do decide to murder you, they have some state-of-the-art equipment to help them track your ass down.

You may know already that dolphins have sonar that is far superior to their vision, creating their adorable dolphin sounds and detecting how they bounce back. In fact, the sounds they hear create a kind of holographic image in their minds. As in, they perceive echoes as 3-D shapes and textures. Dolphins can "see" sound, kind of like Daredevil, or those Batman sonar goggles in The Dark Knight. And if that wasn't cool (or weird) enough, they can look right inside of you.

The short explanation is: radioactive ocean spiders.

That is, their ultrasonic clicks penetrate flesh, giving them an X-ray view of your bones and innards. A talent that they've been known to employ when killing other creatures, because they will target vital organs when they attack.

How accurate is it? Well, tests for sensitivity show that they can distinguish a BB pellet from a kernel of corn at 50 feet. One test subject could tell the difference between two objects that differed in width by the length of a human hair from 26 feet. Oh, and they can stun fish with concentrated bursts of sound, too. That's supervillain level shit, right there.
"One more tuna net, motherfuckers. See what happens."

Monte Richard is also a columnist for, and you can check out his blog.

For more ways animals have us beat, check out 5 Animals That Can Do Amazing Things ... With Their Penises and The 6 Most Badass Murder Weapons in the Animal Kingdom.

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