Advertisement

We need your help now

Support from readers like you keeps The Journal open.

You are visiting us because we have something you value. Independent, unbiased news that tells the truth. Advertising revenue goes some way to support our mission, but this year it has not been enough.

If you've seen value in our reporting, please contribute what you can, so we can continue to produce accurate and meaningful journalism. For everyone who needs it.

NOAA Ocean Explorer via Flickr/Creative Commons

These are some of the most mind-bending facts about octopuses

Did you know they can detach their arms? Change their genetic code?

WITH THEIR EIGHT arms and giant egg-shaped head, octopuses (sadly not octopi) are one of the most alien-looking creatures on the planet.

Yet scientists have an extremely difficult time studying them in the wild because these highly intelligent invertebrates are the ultimate masters of disguise.

In her book, Octopus!, Katherine Harmon Courage travels the globe to swim, observe, and even taste some of the many octopuses of the world. Here are some mind-blowing facts she learned about this squishy predator of the sea

Over 95% of all animals on Earth are invertebrates. The octopus is the smartest of them all and has approximately 300 million neurons throughout its body. That’s not much compared to the 100 billion in humans, but it’s a giant leap from the 16 million in frogs.

Polbo / Octopus N. Feans N. Feans

Octopuses are solitary creatures who spend most of their lives swimming alone, even when it comes time to mate.

Octopus NOAA Ocean Explorer NOAA Ocean Explorer

Some, but not all, types of male octopus will steer clear from a female mate. Instead of getting close, he’ll send a package of his sperm to her from a distance, which she’ll grab and store for later.

Coconut Octopus prilfish prilfish

A male will sometimes send a gift along with his package — one of his eight arms, which he severs himself.

Dumbo Octopus NOAA Ocean Explorer NOAA Ocean Explorer

Luckily, octopuses can regrow lost limbs, just like starfish. They can even close off the severed artery to reduce blood loss.

Giant Pacific Octopus Being Playful

When they do bleed, octopuses bleed blue blood, not red. That’s because their blood is high in copper instead of iron.

Meet Fifi laszlo-photo laszlo-photo

Octopuses will sometimes deliberately sever an arm to distract a predator long enough to jet away at top speeds of 25 mph.

Ocean Bodhi / YouTube

An octopus’s brain is located in its egg-shaped head, called the mantle. But the brain does not have complete control over its body. Each arm contains enough neurons to operate semi-independently.

Octopus at Poipu 3 Makuahine Pa'i Ki'i Makuahine Pa'i Ki'i

That means each sucker on the arm can decide when it wants to extend, release, and pinch without requiring a command from the brain to do so. That also means the arms will continue to function for a short time after the arm is severed from the body.

Giant pacific octopus. Three Tree Point, Burien, WA. papertygre papertygre

A special Korean dish called “live” octopus takes advantage of this fact. The chef will take a live octopus, kill it, chop up the arms and serve them while they’re still wriggling on the plate. The dish is often garnished with raw garlic, green onion, and jalapeno.

20101221 fresh octopus schizoform schizoform

Octopus is actually highly nutritious: A 3-ounce serving has 139 calories, 2 grams of fat, 25 grams of protein, 45% of your daily iron value, and 510% of your daily B12 value. As Katherine Courage puts it, octopus “totally trumps any chicken”.

Sizzling squid and baby octopus at Oishii Kitchen in Prahran ultrakml ultrakml

Octopuses have three hearts. The main heart will actually stop beating when the animal is swimming, so it can’t swim very far before tiring out.

day octopus (octopus cyanea), waikiki aquarium brx0 brx0

And sometimes their hearts will skip a beat. In a 1970s experiment, a male octopus’s main heart actually skipped a few beats when a potential female mate was introduced into its tank.

BXP47978 Angell Williams Angell Williams

Because swimming is so tiring, an octopus’s favorite way of getting around is “walking” along the seafloor. They use their back four arms for walking and their front four to probe for food.

expl0792 NOAA Photo Library NOAA Photo Library

But walking is slow and makes the octopus vulnerable to predators. As a result, some octopuses carry protection with them. Here, an octopus is transporting two empty coconut halves it can hide inside of if necessary.

Poussin Diver / YouTube

Octopuses’ most impressive survival tactic is their skin: They can change the color and texture of their skin to blend in with their surroundings and avoid detection. Can you spot the octopus in this photo?

octopuses-most-impressive-survival-tactic-is-their-skin-they-can-change-the-color-and-texture-of-their-skin-to-blend-in-with-their-surroundings-and-avoid-detection-can-you-spot-the-octopus-in-this-photo Screenshot Screenshot

Despite their miraculous color-changing abilities, octopuses are colorblind. Scientists aren’t sure if the octopus is even aware what its skin is doing when it transforms from one colour and texture to the next.

they-can-complete-a-full-body-transformation-in-just-three-tenths-of-a-second-using-the-three-different-color-changing-sacs-in-their-skin-chromatophores-iridophores-and-leucophores-most-other-animals-who-can-change-color-have-only-chromatophores Greg Deocampo Greg Deocampo

In general, octopuses are not picky eaters: Some of the things found in the stomachs of captured octopuses are shocking: clams, crabs, hermit crabs, lobster, and even seagulls. They’ll even venture on land to capture their prey.

Porsche Indrisie / YouTube

Scientists have tested octopuses’ intelligence by placing food inside of jars with screwed caps. The eight-armed creatures easily unscrew the jar for the prize inside. One scientist even discovered one could unscrew childproof caps. Now that’s impressive!

Beata Svengt / YouTube

Octopuses live in small dens such as natural rock outcroppings or confined corners in sunken ships. They enjoy decorating these homes with stones and shiny objects. This behavior inspired the popular Beatles song Octopus’s Garden.

Octopus and his snorkel out of the Den amanderson2 amanderson2

Because of their intelligence, octopuses in captivity will get extremely bored and stressed if they’re not stimulated. In one study, scientists found that octopuses who spent time in bare tanks began eating their own arms from stress but ceased this behavior when placed in tanks with hiding spots and decorative knickknacks.

Polbo / Octopus N. Feans N. Feans

Octopuses can even distinguish one human from another. The most convincing evidence for this comes through anecdotes: A certain watchman at the Seattle Aquarium would always shine her flashlight into some of the darkened exhibits, and the giant Pacific octopus residing in one of them didn’t like it. So every time that particular guard walked by, the octopus would squirt water on the guard to express its annoyance.

Sea Life Octopus Graham C99 Graham C99

One of the most bizarre and impressive qualities of the octopus is its ability to edit its own genes. Octopuses can alter their genetic code by editing their RNA to become more tolerant of cold temperatures, and they can even improve their eyesight to see better in the dark. Scientists are studying this behavior to potentially learn how to replicate this in humans as a possible cure for disease.

Octopus NOAA Ocean Explorer NOAA Ocean Explorer

- Jessica Orwig

Read: Bees are disappearing – and scientists are warning about worrying knock-on problems >

Readers like you are keeping these stories free for everyone...
A mix of advertising and supporting contributions helps keep paywalls away from valuable information like this article. Over 5,000 readers like you have already stepped up and support us with a monthly payment or a once-off donation.

Published with permission from
View 19 comments
Close
19 Comments
    Install the app to use these features.
    Mute John Doyle
    Favourite John Doyle
    Report
    Jan 1st 2016, 10:17 AM

    Fascinating Creatures. Very intelligent

    213
    Install the app to use these features.
    Mute Michael Sands
    Favourite Michael Sands
    Report
    Jan 1st 2016, 9:05 PM

    Yet at the same time they can be so stupid…

    1
    Install the app to use these features.
    Mute Davy Boy
    Favourite Davy Boy
    Report
    Jan 1st 2016, 10:35 AM

    Now That is one thing I was not expecting to start the new year learning about octopuses , Have a great year everyone

    156
    Install the app to use these features.
    Mute bobs_your_aunt
    Favourite bobs_your_aunt
    Report
    Jan 1st 2016, 10:32 AM

    That was an interesting read!
    They still freak me out though!

    134
    Install the app to use these features.
    Mute Kieran Stafford
    Favourite Kieran Stafford
    Report
    Jan 1st 2016, 12:32 PM

    Good soccer tipsters too

    33
    Install the app to use these features.
    Mute Very angry sales rep
    Favourite Very angry sales rep
    Report
    Jan 1st 2016, 11:28 AM

    Very meaty to eat too. Not a fishy texture or flavour but nice

    19
    Install the app to use these features.
    Mute Jamie McCormack
    Favourite Jamie McCormack
    Report
    Jan 1st 2016, 8:37 PM

    Why would you want to eat one of them lads.

    5
    Install the app to use these features.
    Mute Cool Lights
    Favourite Cool Lights
    Report
    Jan 1st 2016, 11:55 AM

    Is see what you did there with the frog joke.

    5
    Install the app to use these features.
    Mute Neil Holland
    Favourite Neil Holland
    Report
    Jan 1st 2016, 3:50 PM

    The plural is Octopodes.

    4
    Install the app to use these features.
    Mute Jamie McCormack
    Favourite Jamie McCormack
    Report
    Jan 1st 2016, 8:44 PM

    It’s Octopusussis. Very angry sales rep ate four of them on Stephensiss Day.

    3
    Install the app to use these features.
    Mute Santa Claus
    Favourite Santa Claus
    Report
    Jan 1st 2016, 2:05 PM

    I heard they have eight testicles too.

    4
    Install the app to use these features.
    Mute Vladimir Vasyectomy
    Favourite Vladimir Vasyectomy
    Report
    Jan 1st 2016, 4:21 PM

    octopi

    2
    Install the app to use these features.
    Mute Neil Holland
    Favourite Neil Holland
    Report
    Jan 1st 2016, 7:04 PM

    Octopodes. A lot of people who think they’re smart think it’s “octopii”. They’re usually the same ones who don’t know what an acronym really is.

    4
    Install the app to use these features.
    Mute danny corrigan
    Favourite danny corrigan
    Report
    Jan 1st 2016, 1:18 PM

    And best of all, they taste great as calamari

    2
    Install the app to use these features.
    Mute fusha2020
    Favourite fusha2020
    Report
    Jan 1st 2016, 3:30 PM

    That’s squid! Both are very tasty though

    7
    Install the app to use these features.
    Mute Michael Sands
    Favourite Michael Sands
    Report
    Jan 1st 2016, 8:28 PM

    Ate them a few times but out of curiousity, not fair on them to do that to them but if they ate to much themselves they can cause themselves brain damage, crazy creatures?

    1
    Install the app to use these features.
    Mute Jamie McCormack
    Favourite Jamie McCormack
    Report
    Jan 1st 2016, 8:48 PM

    lol

    2
    Install the app to use these features.
    Mute Michael Sands
    Favourite Michael Sands
    Report
    Jan 1st 2016, 8:25 PM

    The great debate… “octopuses (sadly not octopi)” ? lol

    1
    Install the app to use these features.
    Mute tom doyle
    Favourite tom doyle
    Report
    Jan 1st 2016, 4:22 PM

    Shummy i show ya my octopi

    1
Submit a report
Please help us understand how this comment violates our community guidelines.
Thank you for the feedback
Your feedback has been sent to our team for review.
JournalTv
News in 60 seconds