Animals6–8
The Octopus and Its Three Hearts
An octopus has three hearts… and blue blood!
Why?
An octopus has two small hearts that pump blood through its gills to pick up oxygen from the seawater. Then a third, bigger heart sends that blood around its whole body and all eight arms.
Our blood is red because it contains iron, but octopus blood contains copper, which makes it look blue!
Try it
Jump ten times, then put your hand on your chest… can you feel your heart beating? You have only one heart! Then draw an octopus, color it in, and draw three hearts inside it: two small ones and one big one.
Ask Mum & Dad
If we had three hearts like an octopus, what would each heart do?