A couple years ago, some people floated around the idea that octopuses came from another planet. They don't, but there is something almost otherworldly about them. And that's probably because they have tons of strange and amazing adaptations that help them live their best lives underwater. Infact, much like aliens in a sci-fi movie, there's a lot they can teach us. So: Here are eight incredible things we're learning from studying octopuses!

You might have noticed that the undersides of octopus arms are covered in hundreds of little circular things that look - and act - like suction cups. They're super sticky and attached to most surfaces: rough or smooth and wet or dry. And once they're stuck, they can stay that way for a long time without the octopus doing well, much of anything, really. And not only are they energy-efficient, they're also incredibly strong. A sucker the size of a pencil eraser can lift about 150 grams - or approximately a baseballs weight. And each of the roughly six centimeter suckers of a giant Pacific octopus can lift up to 16 kilograms. 

And they have thousands of them. That's a lot of staying power, which is why engineers have taken a close look at octopus suckers to uncover their sticky secrets. Turns out the sides and edges have tiny grooves in them, which increases the surface area for sticking and helps them adhere to rough surfaces. They're also made of super soft tissue, kind of like a jellyfish, which makes them more elastic. And that elasticity allows them to bulge and compress to form a tight seal with different surfaces

Researchers are already using octopus suckers as the inspiration for new adhesives and suction cups that work better than what we have now, like ones that can be removed and restock without losing stickiness. And they can adhere to rough surfaces that would allow us to make all sorts of useful things from adhesive electronics that monitor medical information to grasp your robot arms.

Now, octopus suckers can stick to pretty much everything - and yet, you never see an octopus stuck to itself. This is especially surprising since research has shown that an octopus arms aren't represented in its central brain at all. Each one is controlling itself and moving completely independently.

And in part that's because there are molecules in the skin that inhibit the suckers reflexive crabbiness. But they can choose to have one arm grab another. So even though the central brain doesn't fully control the arms, it can override this. Don't grab molecular signals. Scientists call this kind of partial, centralized command embodied organization. Basically, it's when a controller - in this case, the brain,  a body and the environment all influence each other.

And engineers would love to use a similar strategy and autonomous robots because it makes performing a variety of complex tasks more efficient. Instead of programming the robot central computer with instructions for what each robot body parts should do in every situation, the brain, body and external sensors would learn from the information coming from the other systems. Think about an arm swinging as a robot moves at different speeds. If you had to program exactly how each joint should move to make it swing the perfect amount at all times, you'd have to input a ton of information into the central computer.

But if you're able to rely on the natural physics of the shape of the arm and it can provide feedback to the brain as it moves, you don't need nearly as much initial programming. So this type of embodied organization can make information processing a lot more streamlined and efficient. And that means if robots can "think" more like octopuses, they could do even more cool stuff.

Our arms only have a few joints, each with a limited range of motion. But octopus arms can move in virtually any direction at any point along the arm, including lengthening, shortening or stiffening. This means they can use their arms for everything - from squeezing through the tightest spaces to open in clam shells for food.

And that's why octopus arms are providing inspiration for a new generation of robotics. These robots are soft and flexible, but also able to exert large amounts of force. Some designs use a series of compartments that can be individually filled with air to mimic octopuses movements and other uses cables to recreate the muscle structure that lets octopuses move the way they do.

Either way, researchers are interested in using these soft bodied robots to do things robots with human-like appendages couldn't even dream of, like complete, diverse tasks underwater, but also perform surgery more precisely and in their tiniest form, detect and capture individual pathogens in the body.

Of course, no conversation about octopuses would be complete without talking about their skin. Octopus skin can display all sorts of colors and patterns and even create weird textures to help them blend in with their environment - something we often want our structures, vehicles and personnel to do better.

The colors and patterns of octopus skin are thanks to something called chromatophores. These are organs connected to muscles that can expand or contract when the animal is excited, revealing or hiding the pigments inside and octopuses can manipulate these to match the colors it sees around it - either with its eyes or potentially with light-sensitive receptors in its skin. On top of this, when an octopus contract certain muscles, sections of skin called papillae pressurize and stretch, causing bumps to appear. So their skin can provide a ton of inspiration when it comes to better camouflage

For instance, some researchers have developed a fabric that has light sensitive sensors embedded in it. When the light changes, the fabric automatically changes between light and dark patterns. Other researchers are creating programmable camouflaging membranes that use air to go from a flat, two dimensional surface to a 3D texture much like papillae. And hopefully that will allow whatever it covers to blend into the background.

Even though octopuses usually move by walking along the seafloor, they can swim. They draw water into a central body cavity and then quickly push it out through a small opening, in short bursts, propelling themselves forward.

This method uses a lot of energy, but it's a really fast and effective way to avoid predators. And moving this way could be a lot faster than conventional propulsion designs like propellers - which is why researchers are basing new underwater propulsion systems on these cephalopods. One such robot was able to travel up to 10 times its body length per second. Plus, since there aren't external blades, boats with octopus-like propulsion could be less damaging to undersea habitats and animals.

Researchers in Germany have even 3D printed one of these, and in addition to moving fast and being less dangerous to marine life, it's completely silent, which would be nice for those on board as well as below the waves. Since marine animals are often scared by boat noises.

Between predators mating and sometimes actually eating themselves, octopuses get injured a lot. But that's OK - They're also masters of regeneration! After being injured, an octopus folds skin over the wound to protect it while it heals. Special cells then remove dead and decaying tissue, keeping the wound nice and clean. And if that wound is an entire arm, they don't just heal the end of the stump. Octopuses can regrow a complete functioning arm (with nerves, muscles, tissue and all) in about 90 days. They can also regrow parts of their hearts - because they have three, you know - and in some rare cases, their corneas. And maybe even parts of their brain?!

All of which we would love to be able to do for ourselves. It's literally the entire point of the field of regenerative medicine, which is why lots of researchers are studying octopus healing in extreme detail. They want to know everything - the types of cells involved, what they do, how everything gets reorganized, you name it - because all of it can teach us more about how to regrow damaged human tissue. And octopuses are especially great for this research because they regenerate so many different types of organs and cells. We haven't used any intel from octopuses to actually regrow our body parts yet, but just give those researchers a little more time.

Despite their ability to regenerate, octopuses do eventually die... usually after reproducing. After a female octopus lays tens to hundreds of thousands of eggs, she settles in for the long haul. She'll protect them until they hatch, never leaving them unattended - not even to grab a snack. For most octopuses, mommy duty lasts a few weeks to a few months. But in one extraordinary case, a mother octopus washed over her brood for 53 months!

That's four and a half years without eating or doing anything else. That's dedication. And it almost makes me feel better about the fact that afterwards she rested... forever.

Now, this extreme motherhood is interesting and all, but it might not seem super relevant to us. But the key thing to realize is that after all this, the female doesn't die because she starves. Rather, it's because she ages. And when her duties are complete, hormonal signals tell her cells that it's time to let go completely. It turns out that the drive to ignore everything except parental duties and the wave of programmed cell death are both controlled by a gland behind her eyes called the optic gland.

If this gland is removed, the mama octopus will abandon her nest, go in search of food, gain weight and sometimes even mate again. And she'll live significantly longer than octopuses who wait around for their eggs to hatch. But what's especially interesting is that this gland is the octopus equivalent of our pituitary gland. That means studying it could help us understand what our pituitary gland does and in particular, its role in aging. And a deeper, molecular level understanding of how and why these mammals die the way they do could, just maybe, provide clues for keeping people or their tissues alive longer.

That's not the only life-extending trick octopuses may have hiding up their sleeves. They may also be a great source for pharmaceuticals. That's because, get this, all octopuses are venomous. Research suggests they gained their toxic abilities at least 300 million years ago before they split from their cephalopod cousins like cuttlefish. These venoms can help keep predators away from their soft, unprotected bodies, but mostly they're useful for hunting. They can drill into their prey shell and inject a paralytic venom. Then with the meal immobilized, they can liberate the tasty meat from its protective casing. And these venoms can pack more of a punch than you might think. For instance, the tiny blue ringed octopus can actually kill a human with a single bite! But, they might also help us live longer.

Venoms in general are super useful for developing new drugs. That's because the toxins in them often have very specific targets, which means they can be used to do really specific things to our bodies. That's what you want in a pharmaceutical since, you know, side effects aren't awesome. Drug developers have tapped venoms for drugs that modulate the immune system, keep blood from clotting, shrink tumors, and kill microbes.

But since only recently learned that all octopuses are venomous, we've only begun to examine their potential. Really, that's true of most aspects of octopus biology - there's still a lot we don't know about them. So while we're learning a ton from these octo-armed creatures, plenty of opportunities remain to discover bizarre and surprising features.  And when we do, we'll probably be able to borrow from them to develop new technologies and learn about ourselves. 

But if you don't want to wait to keep on learning, you might be interested in a course from Brilliant. Like their course on knowledge and Uncertainty. Because there is a lot of uncertainty out there right now, this course is designed to give you the tools to understand what we don't know and deal with the flood of information we're exposed to, day in and day out. Brilliant has a ton of interactive, engaging courses designed to help you sharpen your skills in science, engineering, computer science, and math.

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