Carnegie Museum of Natural History was able to find a rare and unique bird in the Pennsylvanian forests on September 24. What makes this bird unique is that it is half-male and half-female, genetically.
Researchers were able to catch this bird at the Powdermill Nature Reserve in Rector, Pennsylvania. According to the biologists, this bird is split down in the middle with the features of both males and females, including the colors.
The unique bird in question is of a species called the rose-breasted grosbeak found in eastern North America. It comes from the cardinal family and is a seed-eating species. As you know well, the males are more beautiful than the females in the bird family. The males of the rose-breasted grosbeak are of vibrant plumage, while the females are of a brown-orange color.
Interestingly, this specific bird that the biologists of the museum caught has one side of its body in rosy red and the other side in brown-orange, features of both the male and the female half-and-half.
In science, this rare condition where an animal’s outer appearance is divided down the middle by sex, is known as “bilateral gynandromorphism”. Wondering about the process behind this? Well, in birds, the males feature double sex chromosomes (ZZ) while the females feature one of each (ZW). If an egg has two nuclei (one with a Z and the other a W), and is fertilized by sperm with two male Z chromosomes, then the egg develops with both ZZ (male) and ZW (female) chromosomes.