Assertion: otter's undercoat | /r/CapableOf | trap air
Facets:
Source sentences:
text: They actually have two layers of fur: a dense undercoat that traps air and a topcoat of long, waterproof hairs.
text: That’s because otters have two layers of fur: a dense undercoat that traps air and a topcoat of long, waterproof guard hairs.
text: It’s incredibly dense with two distinct coats – a long, coarse outer coat (guard hairs) and a short and wooly undercoat that traps air and insulates.