The Two Other Hearts (the branchial hearts).As soon as it starts swimming, this heart will stop pumping. Only active when the Octopus is not moving.This heart is in charge of pumping the blood around in the body of the octopus.LetвЂ™s take a closer look at what their hearts do: They have a closed circulatory system like mammals that carries oxygen and nutrients around the body. LetвЂ™s try and uncover these creatures and see why they need an additional heart and what it is used for. The Sea Cucumbers are probably the only animal from the small list above that does look a bit like an animal that could have a heart.ДЄctually, we also find animals with multiple hearts. They are super-simple creatures as well and they donвЂ™t have internal organs. ThatвЂ™s not so hard to believe when you see them. Other sea creatures also live without a heart.

Five More Simple Sea Creatures Without Hearts: They live off of Zooplankton and oxygen from photosynthesis made by tiny plant-like creatures that grow on the corals. But in fact, corals are animals.Д¬orals have no blood or vessels so thereвЂ™s no need for a heart! They are much simpler animals and many people think corals are flowers or plants. Scientists have managed to вЂњspawnвЂќ more than 100 worms from one single Flatworm! But the severed part also continues to grow to become its own Flatworm! Much like Jellyfish, you can cut off one part and another grows back. The Flatworms are amazing because they can regenerate. Instead, they rely on a process called вЂњdiffusionвЂќ to circulate life-giving oxygen and nutrients transported through the body.Дiffusions is a process where the oxygen and nutrients will simply flow by themselves as the worm moves. They have no circulatory system at all and they have no respiratory organs such as lungs. The Flatworms are so flat they have no heart. If you hurt it or it bumps into a coral and loses a piece of itself, it simply will just grow that piece again.Д«ecause there is no heart or organ system to eventually grow old and to fail, scientists suspect that maybe the Jellyfish can even live eternally!Д¬heck out our article, Why Do Humans Live Longer Than Animals? for more information on animal lifespans! This has led scientists to point out that the Jellyfish does not have a maximum life span. Just like a salamander can regrow a new tail! On top of these cool facts, it can even regenerate itself. Later, once it has digested the food, waste will leave the jellyfish body through that same opening. It is by far the biggest animal without a heart.ДЄ jellyfish will eat whatever swims by, grabbing tiny fish and Zooplankton with its tentacles in order to direct the food into its mouth. Some jellies can grow up to 8 feet (2,5 meters) and when you add the tentacles we are talking more than 50 feet! (15 meters). The Jellyfish is truly strange because it mostly floats around in the ocean unconsciously. It doesnвЂ™t even have a brain.ДЄ jellyfish has no heart because it has no blood flowing around inside its b ody. The Jellyfish is a very simple and primitive creature. Look at how they can function and live without the life-giving oxygen that humans (as well as most animals) are so dependent on: 1) Jellyfish Now, letвЂ™s look at a few animals that are NOT dependent on a flow of oxygen and nutrients. So in order for the body and the internal organs to function properly, they are 10% dependent on the constant flow of blood. The function of the heart is to pump the blood around.Д«ecause the blood carries oxygen and nutrients for the body. Why Do Animals Have Different Sized Hearts?.Which Animals Have No Brain (or Heart)?.Five More Simple Sea Creatures Without Hearts:.

Octopus hearts