The Bilateral Gynandroporph Northern Cardinal
This rare picture is of an even rarer bird, the bilateral gynandromorph northern cardinal. This cardinal has bilateral asymmetry, which means that one side is female and one side is male. In this case, the bird’s left side is female and the right is male. This condition is most often found in the Evening Grosbeak, but was discovered in a Northern Cardinal on Rock Island, II, in 2008. A professor who monitored the bird for two years said it was unclear whether the bird ever mated, but it was clear that the bird was subject to aggressive attacks by other birds.