Most tend to live alone, although some types do live with others in small groups.
some are solitary but most travel in groups called herds
Yes this is most likely caused because they are constantly feeding. And there are only a few spots where they can feed themselfs.
Groups you idiot
no
in schools
Sea stars, brittle stars, sea urchins, and sea cucumbers.
California sea lions do live in groups.
sea anemones live in groups
in groups
the water
There are actually four major classes of echinoderms. These are Crinoidea, Asteroidea, Ophiuroidea, Eichionidea, Holothuroidea, and Concentricyloidea. The animals in these range from sea lilies to sea urchins.
groups
britle stars are small and live in coral reefs and are eaten by GIANT sea stars
Tropical
Echinoderms are invertebrates with an internal skeleton and a system of fluid-filled tubes called a water vascular system. There are four major groups of echinoderms: sea stars, brittle stars, sea urchins, and sea cucumbers.
Niche
they have sex and they live in vthe ocean