Assertion: starfish | /r/CapableOf | use chemical signals
Facets:
value: to indicate their readiness
type: PURPOSE
Source sentences:
text: To increase their chances of fertilization, starfish probably gather in groups when they are ready to spawn, use environmental signals to coordinate timing (day length to indicate the correct time of the year, dawn or dusk to indicate the correct time of day), and may use chemical signals to indicate their readiness to each other.