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1. The octopus is a fascinating creature with three hearts.
2. The earthworm has five pairs of hearts throughout its body.
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3. The hagfish has four hearts in total, allowing for efficient blood circulation.
4. The cockroach possesses a network of 13 chambers that act as "hearts."
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5. The squid has three hearts that pump blue, copper-based blood.
6. The blue whale has a heart the size of a small car.
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7. The fruit fly has a simple tube-like heart that pulsates to circulate blood.
8. The garden snail has two atria and a single ventricle in its heart.
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9. The grasshopper has a single tubular heart that pumps blood throughout its body.
10. The amphibian axolotl has three chambers in its heart.
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11. The salamander has a three-chambered heart for efficient circulation.
12. The fish has a two-chambered heart that pumps blood through its gills.
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13. The starfish has a simple water vascular system that circulates nutrients and oxygen.
14. The crayfish has a tubular heart that pumps blood through its body.
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15. The jellyfish has a simple network of canals that act as a "heart."
16. The insect beetle has a segmented heart that pumps blood throughout its body.
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17. The worm has five pairs of "pseudohearts" that help circulate fluids.
18. The squid has three hearts that pump blood to its gills and body.