Twelve thousand years ago in what is now Jamaica, there lived a small, flightless bird that at first glance would seem harmless. It was about the size of a chicken, just looking for worms. However, if it felt threatened, it would raise its wings; not to fly, but to use them as bludgeons.
The species, called Xenicibis, used its wings like clubs against its foes. Specialized bones hinged at the wrist were wielded like nunchucks and could deal powerful blows.
When study co-author Nicholas Longrich of Yale University first saw the skeleton, he first believed that the unusual bones were evidence of a deformity.
“There are a lot of birds that do have weaponry,” Longrich told National Geographic News. “They just don’t have anything like this.”
Some of the skeletons showed injuries from prior conflicts. One had a fractured hand bone, while another had a bone snapped completely in half. Researchers like Longrich look to related living species to try to determine how the birds used these weapons. Modern Ibis birds, which are the Xenicibis’s closest living relatives, routinely fight each other for territory. Longrich believes that Xenicibis also had to deal with predatory threats.
“Most flightless birds, like the dodo, had absolutely no predators around. But Jamaica had many snakes, raptors, and other potential predators,” Longrich said. “So maybe they just needed a bit more defense.”
The fossil record is not detailed enough to know what caused the extinction of these flightless birds.
– Amy Stewart