Assertion: fur seal's pup | /r/CapableOf | thicken their blubber layer
Facets:
value: quickly
type: MANNER
Source sentences:
text: Harp seal milk initially contains 25% fat (this number increases to 40% by weaning as the mother fasts) and pups gain over 2.2 kilograms (4.9 lb) per day while nursing, quickly thickening their blubber layer.