Half-Female, Half-Male Green Honeycreeper Bird Spotted
A Green Honeycreeper exhibiting half-female, half-male plumage, a rare phenomenon known as bilateral gynandromorphism, was documented in Columbia by a University of Otago zoologist. This second recorded instance in over a century offers valuable insights into avian biology.
By Beth Snider · January 8, 2024
In a rare occurrence, a zoologist from the University of Otago, Professor Hamish Spencer, recently documented a sighting of a Green Honeycreeper with a distinctive half-female and half-male plumage. This phenomenon, scientifically known as bilateral gynandromorphism, occurs when an error in female cell division results in an egg that undergoes double fertilization by two sperm. This remarkable discovery is only the second recorded example in over a century.
While on holiday in Columbia, Professor Spencer stumbled upon the extraordinary bird while guided by amateur ornithologist John Murillo. The Green Honeycreeper exhibited typically male plumage on its right side and female plumage on its left, creating a visually striking sight. The features were captured in a short video shared by the University of Otago, providing a rare glimpse of this avian anomaly.
Displaying both male and female characteristics is exceptionally rare across various species. Professor Spencer expressed his privilege at witnessing such a phenomenon, emphasizing that many birdwatchers could go their entire lives without encountering a bilateral gynandromorph.
The recorded instance of the Green Honeycreeper is only the second documented case. Experts recognize the photographs taken during the encounter as possibly the best documentation of a wild bilateral gynandromorphic bird across all species, invaluable for advancing our understanding of sex determination and sexual behavior in birds.
Gynandromorphs play a crucial role in advancing scientific knowledge, especially in species with strong sexual dimorphism. The Green Honeycreeper’s example showcases that either side of the bird can exhibit male or female characteristics. Professor Spencer hopes this rare discovery will inspire people to appreciate and cherish exceptions in the natural world. Encouraging a constant lookout for oddities, he challenges enthusiasts to seek out unusal occurrences, suggesting that these exceptions often reveal fascinating aspects of biology.