Green honeydew (chlorophane spizaseThe male’s plumage on one half of the body and the female’s on the other half was recorded on camera for the first time, the only other known recording being made more than a century ago. This impressive-looking bird has glossy teal and yellow-green plumage with a distinctive border down the middle. This differs from the typical males of this species, which are bright blue and black-headed, and the females, which are entirely grass-green.

Amateur ornithologist John Murillo spotted the unusual creature at a bird feeder on a small farm in a nature reserve near Manizales, Colombia. He pointed out the unusual bird to Hamish Spencer, a professor of zoology at the University of Otago, New Zealand, who was on leave in Colombia at the time.

The unusual disparity in this bird’s colors is due to double gynandromorphism, which is thought to be caused by an error in the division of the egg-forming cell in birds, allowing the egg to be fertilized by two different sperm.

“Many birders can go their entire lives without seeing a bilateral gynandromorph in any bird species,” says Spencer. “This phenomenon is extremely rare for birds, I know of no examples from New Zealand. It is very impressive, I was very honored to see it.”

For 21 months, the bird returned regularly to feed on the fresh fruit and sugar water the farm’s owners dropped off daily.

“But the bird was not around every day. Indeed, it remained nearby for about 4-6 weeks and then disappeared for about another 8 weeks,” the authors note.

A gynandromorphic bird would often wait for other birds to leave before approaching.

“He generally kept his distance from other members of his species, and others kept their distance from him; therefore it is unlikely that this individual would have had the opportunity to reproduce,” the authors write.

Since birds do not have sex hormones spread throughout their bodies like humans, it is possible that the internal organs of this bird are divided into male and female in the middle; This is a situation that cannot be confirmed by appearances alone.

Bilateral gynandromorphism is one of the wonders of the animal world and has been observed in spiders, songbirds, butterflies, lobsters, chickens, and stick insects. Spencer says we should “preserve the exceptions” in nature and always be “alert for oddities.”