This audio story is brought to you by BirdNote, a partner of the 探花精选. BirdNote episodes air daily on public radio stations nationwide. 7589 Transcript: This is BirdNote. Two herons—one dark, the other white—feed at the edge of a wooded pond in the South. The dark bird has a blue-gray body and red-violet neck. The other is pure white. Yet both birds are Little Blue Herons. What’s going on here? Why the color change? Well, the white bird is a juvenile. These young herons benefit from foraging with flocks of Snowy Egrets, which stir up prey. The white immatures mix readily with the white egrets and, by this mimicry, gain a better chance of getting a meal. The dark birds are adult herons, toward which Snowy Egrets are aggressive. Dark herons, in general, tend to be solitary and quite aggressive even to each other. By arraying the immature Little Blue Heron in white, nature helps the young bird survive the vulnerable early years of its...