

8 Fun Facts About Octopuses

Octopuses are also romantic.


octopus in the sun

Octopus in back light. Shot captured in the wild.
Copyright: PlanctonVideo Used with permission.

We don’t need to rocket into deep space to encounter enigmatic alien creatures …just plunge into the deep sea. Yes, I’m speaking of Octopuses.

Octopuses Have Three Hearts 

Two of their hearts pump blood to the gills, while a third circulates it to the rest of the body. When the octopuses swim their major heart ceases to beat. That’s why they can’t swim too far before tiring out. So, they prefer striding across the seafloor. They walk on their four back arms, while they probe for food with their four front arms. However, they’re vulnerable to predators when walking, so they sometimes carry protection with them. 

Here is a video of an octopus carrying an empty coconut halve so it can hide inside it if necessary. 

Octopuses are also romantic. No, I’m not kidding. Hearts skipping a beat—it’s not just a mushy romance line. An experiment in the 1970s documented a male octopus’s main heart skipping a few beats when a prospective female mate joined him in his tank.

Octopuses Have Nine Brains

The Octopus nervous system includes a central brain about the size of a walnut. You can say that each of an octopus’ nine arms has a mind of their own— a large ganglion at the base of each arm that controls movement. Two-thirds of an octopus’ neurons reside in its arms. So, its arms can figure out how to open a shellfish while it’s major brain is checking out a cave for food. The arms even react when they’re completely severed, jerking away in pain when pinched.

In 350 BC Aristotle wrote in the History of Animals, that octopuses are stupid. The great philosopher was wrong about the octopus. Scientists tested the octopuses’ intelligence by placing food in jars with screwed caps. Effortlessly, the octopuses unscrewed the jars to get the treat inside. One of the creatures even managed to remove a childproof capthat’s pretty smart.

They can also navigate mazes, take things apart, solve problems and remember the solutions. They even have distinctive personalities. Moreover, octopuses can tell one human from another. For example, a guard at the Seattle Aquarium use to shine her flashlight into the dark exhibits, which annoyed a giant Pacific octopus, so he squirted water at her alone, every time she walked by.

Since octopuses are smart, they get bored and stressed if they’re not stimulated. A study found octopuses held in bare tanks, began eating their own arms from stress. However, they stopped that when given tanks with hiding spots and pretty knickknacks.

Octopuses Have Blue Blood

Octopuses have copper based rather than iron-based blood, which is why it’s blue. Their blood is better than hemoglobin for transporting oxygen when water temperature is really low and oxygen is sparse. But this system also causes extreme sensitivity to change in acidity. If the surrounding water’s pH dips too low, octopuses can’t circulate enough oxygen. As such, researchers worry about the dire effects climate change-induced ocean acidification may have on them.

Octopuses Change Color

As a survival tactic, octopuses transform the color and texture of their skin to blend in with their environment, so they’re invisible to predators. With three different color-changing sacs in their skin: chromatophores, iridophores, and leucophores, octopuses can complete a full-body transformation lickety-split—in three-tenths of a second. A scientist documented a single octopus changing colors 177 times in an hour. 

They also use their skin-changing abilities when hunting. They stun their prey with a fatal bite that injects neurotoxin. Most of these toxins can’t kill a human, but the blue-ringed octopuses’ bite inserts enough venom to kill 26 adults in minutes.

Octopuses Are Squishy

Most octopuses can squeeze through any hole no smaller than its mouth—which is a hard beak.

Octopuses Can Edit Their Genes

They can alter their RNA to see better in the dark and better tolerant cold temperatures. Scientists are trying to replicate this ability in humans as a cure for diseases.

Octopuses Lay up to 400,000 Eggs 

Multiple males either insert their spermatophores into a tubular funnel that the females breathe with or they hand the female their sperm, which she accepts with one of her right arms. Then, the males wander off to die. The females lay up to 400,000 eggs, which they guard and tend to. During this time, they stop eating. When her eggs hatch a torrent of cellular suicide occurs from her optic glands through her tissues and organs until she dies.

Octopuses Can Taste Food With Their Fingers (Suckers)

With chemoreceptors in their suckers, Octopuses can taste food by picking it up. Their strong arms can pry open pretty much any mollusk shell they come across. They even venture on land to capture their prey. They have 240 suckers per arm and each one can hold about 35 pounds. 

I became fascinated with octopuses when I did a workshop with Cornelia Amiri on these fascinating creatures and ended up putting on in a book (Specters in the Storm).

Did you learn something you didn’t know?

Perilously yours,



