Assertion: sea urchin | /r/CapableOf | form large aggregations
Facets:
value: sometimes
type: TEMPORAL
value: in open exposed areas
type: LOCATION
Source sentences:
text: While often solitary, sea urchins sometimes form large aggregations, which help to protect the invertebrates from predators.
text: However some sea urchins such as Diadema sometimes form large aggregations in open exposed areas.