Hummingbird

Each night, a Hummingbird enters torpor: its heart slows from up to 1,200 bpm to under 50, body temperature drops from 40°C to ~10°C, and metabolism falls 95%. Without this near-death energy saving it could starve before dawn; wing-muscle tremors wake it before sunrise.

Hummingbirds do not draw nectar through capillary action — their tongue is a fluid trap. The forked tip opens when it touches nectar and snaps shut as the tongue retracts, scooping up liquid in the process. The finding overturned a century-old textbook explanation.