You've heard of people who can light up any room they walk into? Well, these guys literally do that!

Bioluminescent animals are organisms that can produce, and emit their own light. They can be breathtakingly beautiful, or they can be downright terrifying. About 90 percent of our oceans’ deep water dwellers use bioluminescence, but these light displays aren’t just limited to marine life.

On dry land, there are living things like flies, worms, and even fungi that can light up the night. Wondering how any of this is even possible? Let us shed some light on the topic.

The mesmerizing glow that we see when we’re lucky enough to come across this phenomenon is created by a chemical reaction. The color of the glow can vary from species to species, depending on their habitat. It can be blue, green, yellow, or red. And it’s used for more than just a built-in flashlight. It can attract, repel, camouflage, defend, and communicate.

Can these animals control when they light up? Why do most of these animals emit a blueish green light? And how do they use this ability to save their lives?

Today you’re going to be lucky enough to meet some of the most famous Bioluminescent creatures. You’ve heard of people who can light up any room they walk into? Well, these guys literally do that! Except for the walking part, that is. There’s the Angler Fish, who uses its light to lure prey out of the dark, and into its razor sharp teeth. There are Jellyfish, who defend themselves by startling predators with their sudden glow. And there are Squid, who use their light to camouflage themselves, through a process called counter-illumination.

But for now, it’s back to the stars of the show. When Bioluminescent organisms release energy, it doesn’t come out in the form of body heat like it does for humans. Instead, they release a unique compound called Luciferin which, when exposed to oxygen, creates a chemical reaction that emits light. These creatures can control when they light up. They’re able to regulate their own chemistry with the help of their nervous system.

But not everyone’s light comes out the same color. Most of the bioluminescent ocean-dwellers emit a blue-green glow, because the short wavelengths of these colors travel the farthest, and can be recognized by most underwater species.

Most deep sea animals can’t see the color red, because its long wavelengths never make it to the bottom of the ocean. As a result, a lot of them have evolved to be the colour red, in order to make themselves invisible.

But some animals like to be different. This is the cute and cuddly Dragonfish, and they’ve evolved to emit their own red light. This allows them to see red colored prey, and communicate amongst themselves, without alerting any unsuspecting targets. That’s some serious spy equipment.

Here’s a question: Which of the following familiar species possesses bioluminescent abilities? Is it cats, humans, or pigs?

Well, surprisingly, it’s Humans! According to a 2009 study by Japanese researchers, we emit our own visible light, it’s just not strong enough for our eyes to detect. Using highly sensitive cameras, the researchers were able to capture the first images of human bioluminescence. Our production of light works pretty similarly to other organisms, a chemical reaction that takes place when we release energy. One of the main differences though, is that we haven’t evolved to have any practical use for it. Yet.

In the animal kingdom, bioluminescence serves a variety of purposes. It can be used to help find your next meal, not only by illuminating your hunting grounds, but also by luring in your prey, the way the Cookie Cutter Shark does to whales and squid.

It’s also useful for attracting other animals for mating purposes. For instance, Fireflies not only use their light to identify themselves to members of the same species, they also employ specific flashing patterns to distinguish which sex they are.

And, if you’re a creature that doesn’t want to be noticed, you can use bioluminescence for that too. Marine animals like squid produce light to match the dim rays coming from the surface of the ocean. When predators look up, it’s hard to see the squid, they just blend in with their background.

So, while these glowing animals might look like they’re supernatural, there’s actually a lot of science, and practicality behind them.