By Brooklynn Then, age 10
The oldest octopus fossil we have is about 330 million years old.
Octopuses have rounded bodies, bulging eyes, and eight long, lanky tentacles. Octopuses generally live in warm and tropical water at varying depths and in dens.
Octopuses have nine brains: one in their head and one in each tentacle (also called ganglia). An octopus has three hearts—two pump oxygen into the blood, and the third heart pumps out oxygenated blood. Octopuses might spew out an inky fluid from their bodies or camouflage themselves. Jon Ablett, who cares for the cephalopod collection at the Natural History Museum in New York City, explains, “Thousands of specialized cells under their skin, called chromatophores, help them to change color in an instant. In addition, they have papilli—tiny areas of skin that they can expand or retract to rapidly change the texture of their skin to match their surroundings.”
Climate change deeply affects octopuses because they are very sensitive to changes in acidity. Overfishing of their food supply and pollution destroy their habitats and also harm octopuses.
