Ocean Species Profile: Purple Sea Urchin

Hello! My name is Daisy, and I am a sea urchin - a purple sea urchin to be exact!  Scientists sometimes call me Strongylocentrotus purpuratus, but I really do prefer Daisy. I'm about 3 inches across, and you might say I look like a pin cushion. That's because I'm made up of a round inner shell, called a "test," which is covered in purple spines. My spines are attached by a ball and socket joint, similar to your shoulder. Look at that! Even though I am an invertebrate, meaning I have no spine, we still have something in common! At least you're not covered in spines. Can you imagine trying to go to school covered in big purple spines? 

Daisy and Otto Children's Book

I love my spines, though. They protect me from predators and help me to catch food, which is normally green or brown algae. I am also covered in tiny tube feet, which are exactly what they sound like: tubes that extend out and allow me to move around like your feet do for you. Unlike you, I also breathe through my tube feet, so I'm glad I don't have to wear socks and shoes!