An octopus has three hearts and long arms with suction cups. It probably seems very different from you. But you have the main ingredients of octopus ink in your body, too!

Gretchen Rollwagen-Bollens.
Rollwagen-Bollens

I talked about octopus ink with my friend Gretchen Rollwagen-Bollens, associate professor in WSU’s School of the Environment. She told me that ink isn’t just an octopus thing. Most animals called cephalopods (sef-uh-luh-pods) make it. These include octopus, squid and cuttlefish.

Cephalopods including octopuses use color a lot. They have sacs of colored pigments all over their bodies. They use those sacs to change their body color. That helps them blend into their environment.

They also make and store a dark pigment in special ink sacs.

“Squid ink looks dark because it contains molecules of melanin, which is a pigment,” Rollwagen-Bollens said. “It’s the same pigment that you find in human skin. The more melanin skin cells contain, the darker they are.”

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Dr. Universe