Assertion: sea cucumber | /r/PartOf | a group of animals
Facets:
Source sentences:
text: Sea cucumber is a marine creature that belongs to a group of animals called echinoderms, which also includes starfish and sea urchins.
text: Related to starfish and sea urchins, sea cucumbers belong to a group of animals known as echinoderms and make a living on the seafloor.