Nicholas Longrich from Yale University and Storrs Olson from the Smithsonian Institute have discovered a novel fighting strategy in an extinct ibis. Apparently, the birds would bludgeon each other with their club-like wings.
Xenicibis xympithecus lived in Jamaica about ten thousand years ago. A flightless member of the ibis family, Xenicibis was about the size of a large chicken. Newly discovered skeletons revealed that the bird had wing bones unlike any seen before. Rather than being greatly reduced like most flightless birds, the wings contained thick curved hand bones hinged at the wrist joint. In two cases, the bones showed obvious signs of combat, including broken hand and arm bones. The paleontologists concluded that the birds would batter their rivals with their cudgel-like wings.
This behavior was so unprecedented that, in referring to the skeletal discoveries, Longrich stated,
When I first saw it, I assumed it was some sort of deformity. No one could believe it was actually that bizarre.
The prehistoric Xenicibis used its wings like two clubs hinged at the wrist joint in order to swing at and attack one another.Credit: Nicholas Longrich/Yale University.