How many hearts does an octopus have facts for kids
It is truly mind-boggling, but an octopus has not one, not two, but three hearts! Two of them pump blood to the gills, while the third pumps it to the rest of the body. Let's dive in and learn how they all work together.
How they work
Two of the hearts are called branchial (pronounced BRANK-ee-ul) hearts, and you can think of them as the “gill helpers.” Their one big job is to pump blood all the way to the gills, which is how an octopus breathes. Just like our lungs take in oxygen from the air, gills take in oxygen from the water. These two hearts work hard to make sure the blood gets filled with fresh oxygen so the octopus has plenty of energy.
Once the blood is full of oxygen, it flows to the third heart, called the systemic heart. This is the "body boss," and its job is to pump that oxygen-rich blood out to the rest of the octopus’s soft, squishy body. It sends blood to the brain, the eyes, and especially to all eight wiggly, super-smart arms, which have their own mini-brains and need lots of oxygen to work their magic.
The really wild part
Here's a cool twist: the hearts don't always beat at the same time. When an octopus swims, its systemic heart actually stops beating! Because swimming takes so much effort, the octopus's body lets the main heart rest and relies more on the two gill helpers. This is hard work, though, so the octopus gets tired quickly when swimming and much prefers to crawl along the seafloor using its arms.
A colorful bonus
Oh, and here’s one more thing to make you say “Wow!”—an octopus’s blood is blue, not red like ours. That’s because they use a copper-based protein called hemocyanin to carry oxygen, instead of the iron-based hemoglobin that makes our blood red. Pretty awesome, right?
