This delicate feather star is resting on a piece of coral.
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Windows Original, adapted from Corel Photography

Echinoderms

The most widely known echinoderm is the sea star, or starfish. But the echinoderm phylum also includes sea urchins, sea lilies and brittle stars. The echinoderms are very well known, but most people actually don't know what category to put them in!

The Crinoidea class contains sea lilies and feather stars. These delicate creatures are very beautiful, with several arms stretching out from the center. Echinoderms don't have a head, instead they appear to be groups of legs tied together at the middle!

Sea stars are widely known due to their famous shape. It is a common belief that they all have five legs, but that is actually not the case. The Eleven-armed Sea Star has, you guessed it, eleven legs. Regardless, sea stars can be spotted on rocks, sand, mud or reefs. They come in a variety of colors, and sizes.

Sea stars have some very weird characteristics. First of all, they invert their stomachs to feed on molluscs and other invertebrates. Secondly, they can grow back any legs they may lose!

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