a very rare half-male, half-female bird observed in Colombia

The Emerald Tanager photographed in Colombia has very particular plumage, blue on one side and green on the other. In 100 years of observation, this is only the second case of gynandromorphism reported in this species.

It is a quirk of nature, an extremely rare phenomenon, a half-male, half-female bird was recently observed between October 2021 and June 2023 in Colombia. The results of this discovery were published in December in the magazine Journal of Field Ornithology.

The colors of this little bird caught the attention of an ornithologist. He had time to take out his camera to immortalize the moment. Sitting on a branch, this bird has a very particular plumage: half blue, the other half green. Both being well demarcated. Visually, it’s very pretty, but scientifically it says a lot about the particularity of this bird. This is a case of gynandromorphism, an animal exhibiting both male and female characteristics. In this case, in this bird, called Emerald Tanager, the green part corresponds to its female side and the blue part to its male side.

An unusual phenomenon among birds

We also observe this type of phenomenon in other animals, especially insects, butterflies and lizards, but for birds, it is much rarer. In 100 years of observation, this is only the second case reported in this species of birds. However, be careful not to confuse it with hermaphroditism, which corresponds to the presence of male and female reproductive systems. Gynandromorphism applies to individuals where one part of the body has male characteristics, and the other part has female characteristics. This phenomenon would be linked to an error during fertilization. If we take the example of this bird in Colombia, it could therefore have an ovary on the left and a testicle on the right, as has been observed in other individuals.

Scientists noticed that this half-blue, half-green bird had a tendency to come and feed after the other birds, to live a little on the fringes. The other Emerald Tanagers seemed to avoid him. It is also impossible to know whether the specimen was sterile or not. In any case, it does not seem to have had the opportunity to reproduce. For the scientist who publishes the results of this research, this case of gynandromorphism at least allows us to know more about the sexual development of birds.