7 Fascinating Facts About Octopuses That Will Blow Your Mind

Something extraordinary is happening in British waters right now. Record numbers of octopuses — first spotted surging off the coasts of Devon and Cornwall in 2025 — have now spread as far as Scotland, Wales, Dorset and East Sussex. Scientists are calling it the biggest bloom ever recorded in UK waters, driven by warming seas. 

"It is pretty extraordinary," said Bryce Stewart, senior researcher at the Marine Biological Association and lead author of the study. "We have had blooms before but everything I am seeing is telling me this is the biggest bloom we have seen, it is quite different."

Source: The Guardian, 8 June 2026

It's a remarkable moment to get to know one of the ocean's most intelligent creatures a little better. If you had to design the most extraordinary animal on Earth from scratch, you might end up with something a lot like an octopus. Three hearts. Blue blood. Nine brains. The ability to change colour, solve puzzles, and open jars. They've been quietly doing the impossible for over 300 million years — long before the dinosaurs arrived.

Here are seven octopus facts that will make you look at the ocean (and your wardrobe) very differently.

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🐙 1. Octopuses Have Three Hearts and Blue Blood

An octopus has three hearts: two pump blood to the gills, and one pumps it to the rest of the body. That blood is blue — not red — because it contains copper-based haemocyanin rather than the iron-based haemoglobin found in human blood. Copper actually carries oxygen more efficiently in cold, low-oxygen environments like the deep ocean.

Source: Smithsonian Ocean

🧠 2. They Have Nine Brains

Technically, an octopus has one central brain — but each of its eight arms has its own cluster of neurons, giving it nine semi-independent control centres. Around two-thirds of an octopus's neurons are in its arms, meaning each limb can taste, touch, and react to its environment independently, without waiting for instructions from the central brain.

Source: Natural History Museum

🎨 3. They Can Change Colour — Despite Being Colourblind

Octopuses are masters of camouflage, able to change both the colour and texture of their skin in milliseconds. The remarkable twist? Most octopuses are completely colourblind. Scientists believe they may use the pupil shape of their eyes to detect colour through differences in light intensity — a theory still being actively researched.

Source: National Geographic

🔓 4. They Can Open Jars — and Escape From Almost Anywhere

Octopuses are problem solvers. In aquariums around the world, they've been documented unscrewing jar lids to reach food inside, navigating mazes, and escaping their tanks at night to raid nearby fish tanks before returning to their own. Their bodies are almost entirely soft tissue, meaning they can squeeze through any gap large enough for their beak — the only hard part of their body.

Source: BBC Science Focus

🌊 5. They Have a Very Short Life — and They Know It

Most octopus species live for just one to two years. After mating, a female octopus lays up to 400,000 eggs and spends weeks guarding them without eating — she typically dies shortly after they hatch. Males often die within months of mating. It's a brief, intense existence, and it makes their intelligence all the more remarkable.

Source: University of Chicago Biological Sciences — The Grim Final Days of a Mother Octopus

🖊️ 6. They Use Tools

Tool use was once considered a uniquely human trait. Octopuses didn't get the memo. Veined octopuses (Amphioctopus marginatus) have been observed collecting coconut shell halves, carrying them across the ocean floor, and assembling them into portable shelters — behaviour that meets the scientific definition of tool use.

Source: Current Biology, 2009

🤝 7. They're Surprisingly Playful

Octopuses in captivity have been observed playing — repeatedly releasing objects into a current and catching them, with no apparent purpose other than enjoyment. Individual octopuses have distinct personalities: some are bold and curious, others shy and cautious. Researchers who work with them regularly report that octopuses recognise individual humans and show clear preferences for certain people.

Source: Current Biology — Octopus Play Behaviour

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Wear the Wonder 🌿

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Because some animals are too fascinating not to wear. 🐙

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References

• The Guardian — Octopus surge spreads up UK coast, June 2026
• Smithsonian Ocean — Octopus
• Natural History Museum — Octopuses Keep Surprising Us
• National Geographic — Octopus
• BBC Science Focus — Octopuses: Playful, Choosy and Smarter Than You Think
• University of Chicago — The Grim Final Days of a Mother Octopus
• Current Biology — Tool Use in Veined Octopuses, 2009
• Current Biology — Octopus Play Behaviour