If you were to describe an octopus to someone who knew nothing about them, they’d probably think you were talking about a bizarre mythical creature. Surely nothing can have eight squiggly tentacles lined with hundreds of suction cups as well as the ability to blast out ink when threatened, right?
While octopuses are surely bizarre in more ways than one, those “mythical creatures” are equally as fascinating. Brush up on these 20 octo-facts so the next time you’re attending Octopus Trivia Night at your local tavern, you can dazzle people with your eight-tentacled knowledge.
1. Octopuses are highly intelligent; they’ve been seen unscrewing lids and removing plugs to reach prey. This intelligence causes captive octopuses to become easily bored if they’re not stimulated, so researchers often give them complex toys to play with.
2. When female octopuses lay eggs, they lay them in massive quantities; they can lay up to 400,000 of them at a time! They work tirelessly to protect them, but once the eggs hatch, its every octo for him or herself!
3. Octopuses have the amazing ability to regrow their tentacles in case they’re ever severed. Nearly all animals on Earth would be greatly inhibited after losing a limb, but octopuses produce an influx of a certain protein that makes complete regrowth possible.
4. This sounds strange since octopuses are much smaller than humans, but they actually have two more hearts than we do. Two of them help move blood through the body, and the third keeps circulation flowing to the organs.
5. Because two-thirds of octopuses neurons are located in their tentacles, they have an extraordinary ability to use each arm effectively and efficiently for entirely different tasks at once.
6. Female octopuses are very attentive to their young. In 2018, scientists discovered a massive nursery of octopuses nestling in the rocks. There were thousands of females, which led researchers to believe these octopus “nurseries” are actually quite common.
7. Believe it or not, scientists have found that many octopuses create garden-like displays around their lairs. They’ll collect brightly-colored shells, stones, and pieces of coral and scatter them in a small area.
8. Human blood is red because it’s iron-based, but octopuses have developed copper-based blood, which allows them to thrive in the deep parts of the ocean. This unique blood has a chemical called hemocyanin, which gives it a blue color.
9. Because two-thirds of an octopus’s neurons are located in its tentacles, even if one arm is severed, it still has the ability to move around. During some experiments, severed tentacles made a jerking motion when scientists pinched them.
10. Octopuses are able to transform their entire body color in three-tenths of a second for camouflage. However, scientists believe this change isn’t conscious. Their bodies automatically matches the colors of whatever surface they’re resting on.
11. The third right arm of every male octopus is its reproductive organ, and during the fertilization process, the male will often remove the arm entirely and give it to the female, who stores it in her mantle until she lays eggs.
12. What happens to octopus parents after mating is unfortunate: the males wander off and die within a few months, and the females expel so much energy guarding their eggs before they hatch that they too die soon afterward.
13. If an octopus senses a predator nearby, it will shoot out a cloud of thick black ink to distract its hunter. This ink not only blocks a predator’s view, but it also causes blinding irritation and messes with their sense of taste and smell.
14. Every species of octopus has a certain level of venom protein in their bodies that’s delivered to prey through their beaks. The only species that actually poses a risk to humans is the blue-ring octopus, which has venom strong enough to kill 10 adult humans.
15. Although most octopuses mate with a partner at some point in their lives, they actually prefer to be alone. Even the ones in captivity are kept in separate tanks due to their feisty and competitive nature.
16. Amazingly, there are over 300 species of octopuses throughout the world. The tiniest has arms less than four inches long; the biggest species can reach lengths of 11 feet and weigh 165 pounds!
17. Every octopus has around 240 suckers, and some of the bigger suckers can actually hold up to 35 pounds! People who care for octopuses in captivity have to be careful they don’t allow the tentacles anywhere near their faces in case a sucker finds its way onto an eyeball.
18. Not only do all those tentacle suckers help octopuses grab hold of objects, but the cups also help with their senses of smell. They’ll frequently swim with their tentacles face down over the ocean floor trying to detect food.
19. Octopuses lack both internal and external skeletons, which gives them the incredible ability to squeeze through the tiniest spaces. The only size constraint they have is the diameter of their eyeballs.
20. Most of the octopuses humans eat are imported from Africa. The 1980s saw the booming demand for their meat, and fisheries in Africa started targeting them. Koreans consume the largest amount of octopus yearly.