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Blog: sea urchins

All about urchins

All about urchins

It’s no surprise that these colorful echinoderms are also known as the hedgehogs of the sea: they’re round like balls and covered with long, movable spines. They’re also one of the most popular animals in the touch pools of our Life on the Edge exhibit. 

Feather stars now on exhibit at the Seattle Aquarium

Feather stars now on exhibit at the Seattle Aquarium

Now’s your chance to cast your eyes upon the rarely seen and aptly named feather star. Visit our Puget Sound Fish exhibit to marvel over these graceful echinoderms—you may find it hard to believe they’re related to sea stars, sea cucumbers, sand dollars and sea urchins!

Ocean acidification and sea urchins

Ocean acidification and sea urchins

Like many other invertebrates, sea urchins may be vulnerable to increasing acid levels in the ocean. The hard parts of urchins (such as the sea urchin in our photo) are made up of calcite, magnesium-rich calcium carbonate.

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