8 unique facts about Octopus

1. Octopuses are carnivorous mollusks that live in all oceans and have rounded bodies, bulging eyes and eight long arms.

2. They have three hearts that pump blue, copper-based blood, which is more efficient for cold, low-oxygen environments.

3. Octopuses are the most intelligent of all invertebrates, capable of learning, memory and using tools.

4. Over 300 species of octopus roam every ocean on Earth. Some are under an inch, while others grow up to 30 feet.

5. Octopus arms are super sensors. These can detect chemicals, essentially tasting and smelling whatever they touch.

6. These soft invertebrates can squeeze into holes bigger than their beak and eyeballs. It lets them hide from predators and escape aquariums when boredom strikes.

7. The octopus extracts oxygen from water through its gills. It can also breathe through the skin, which absorbs 41% oxygen requirements while resting and 33% while swimming 

8. When an octopus is not in a hurry, it crawls to  conserve energy. It can go faster by swimming with tentacles. For maximum speed, it expels a jet of water out of a siphon.