“Strange wing” is what its name Yi qi translates to in English. Based on the remains, it has been estimated that the dinosaur lived about 160 million years ago, making it one of the earliest known birds to have ever existed.
Paleontologists identified the creature’s likely small size, long arms, and feathered exterior as well as its small head with teeth suitable for carnivorous eating. However, they were most surprised to observe “long, rod-like bones extending from each wrist.”
After some initial confusion about the bones’ purpose, they found that flying squirrels have a similar feature that provides the structure for a bat-like membrane to be attached. That said, it has still not been confirmed that Yi qi could actually fly, glide, or even flap its wings.