Assertion: anglerfish's light | /r/HasProperty | emitted by their photophores
Facets:
value: to match the ambient light level
type: PURPOSE
Source sentences:
text: The concentration of the photophores on the flanks of the fish also indicate the light's use as camouflage; in a strategy termed counterillumination, the lanternfish regulate the brightness of the bluish light emitted by their photophores to match the ambient light level above, effectively masking the lanternfishes' silhouette when viewed from below.