Birds
In birds with webbed feet, retia mirabilia in the legs and feet transfer heat from the outgoing (hot) blood in the arteries to the incoming (cold) blood in the veins. The effect of this biological heat exchanger is that the internal temperature of the feet is much closer to the ambient temperature, thus reducing heat loss. Penguins have them also in the flippers and nasal passages.
Read more about this topic: Rete Mirabile
Famous quotes containing the word birds:
“Fish got to swim, birds got to fly.”
—Oscar Hammerstein II (1895–1960)
“Birds which are the same color as the foliage in which they nest are less likely to be disturbed by other birds who want to drop in and chat, and therefore last longer.”
—Robert Benchley (1889–1945)
“What a fog! Plane been buzzin’ around overhead for the last half hour. Must be like trying to find your way through the inside of a cow. I never did see such a country. Even the birds are walkin’.”
—Dalton Trumbo (1905–1976)