These Photos Show a Rare Half-Male, Half-Female Cardinal
Bird watcher Shirley Caldwell was looking out at the bird feeders in her backyard when the Erie, Pennsylvania, resident spotted an unusual bird: it was a half-male, half-female cardinal.
Here’s Nat Geo’s biological explanation of how these “male/female chimeras” come to be:
Gynandromorphy like that in this cardinal occurs when a female egg cell develops with two nuclei—one with a Z and one with a W—and it’s “double fertilized” by two Z-carrying sperm.
The chimeric individual then develops with half of its body as a male ZZ and the other half as a female ZW. If you were to examine a cell from the bright red male side, it would have cells with ZZ chromosomes. If you looked at a cell from the left, it would have cells with ZW chromosomes. This phenomenon happens in birds, many insects, and crustaceans.
Here’s a short video Caldwell captured of the same bird:
In 2018, a photographer in Alabama captured a “one-in-a-million” photo of a yellow cardinal.
(via Nat Geo via Laughing Squid)