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An octopus has THREE hearts!

You have just one heart beating in your chest. But an octopus swimming deep in the ocean has three — all beating at the same time!

❤️   💜   💜

One big heart + two smaller helper hearts

Why would an animal need so many hearts? Let's dive in and find out. 🌊

First, what is a heart?

A heart is a pump. It squeezes to push blood around the body. Blood is like a delivery van — it carries oxygen (the "air" our bodies need) to every part.

Squeeze… release… squeeze… — that's a heartbeat.

💡 No oxygen = no energy. Every animal needs a way to move oxygen around, and hearts do that job.

The three hearts & their jobs

Tap each glowing heart to discover what it does. See if you can find all three!

Tap a heart above to reveal its secret job. 👆

0 of 3 hearts found

Two hearts just for the gills

The two purple hearts are called gill hearts. Their only job is to push blood through the gills — the octopus's underwater "lungs" that grab oxygen from the water.

Give the gill hearts a hand! Tap the pump button to send blood through the gills and fill them with oxygen.

💜 → 🌊 → gills → 🫧

Pumps: 0 / 8

💡 More gills to feed = more pumping needed. Two extra hearts make sure the gills always get plenty of blood.

A surprise: blue blood!

Your blood is red because of iron. But octopus blood is blue! It uses a special copper-based helper called haemocyanin to carry oxygen.

The catch: blue blood is not very good at carrying oxygen, especially in cold, deep water. Tap to see why that matters. 👇

The strangest fact of all

When an octopus swims, something odd happens: its main heart stops beating! That's why octopuses get tired quickly and prefer to crawl along the seabed instead.

🤔 Quick think: With blue blood that carries little oxygen AND a main heart that pauses when swimming, why might THREE hearts be so helpful for an octopus?

Match each heart to its job

Tap a job word, then it will jump to the heart it belongs to. Fill both slots!

❤️
Main heart (1 of these)
drop the job here
💜💜
Gill hearts (2 of these)
drop the job here

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You're an octopus expert!

Here's the amazing story of the three hearts:

🌟 Three hearts are the octopus's clever trick for staying full of energy in the deep, cold sea. Nature is full of surprises — keep asking "why"!