The chickadee, for example, weighing just one-third of an ounce, seems a tiny spark of life to throw to the mercy of frigid, 40-m. p. h. winds.

• 例如美洲山雀，体重还不到三分之一盎司，像一个生命小火花，任凭时速40英里的凛冽寒风的吹打。