The largest known eagle in history just received a little more metal, thanks to new research. Modern species eat their food by tearing sections into bite-sized pieces, but the extinct bird known as Haast’s Eagle or Harpagornis ate more like a condor, sticking its entire head into them. carcasses of larger creatures to gut them from the inside out.
Australian biologists have published their findings on the 10-foot-span raptor that has plunged over New Zealand over the past millennia in Proceedings of the Royal Society B: Biological Sciences this week. They studied the bird’s morphology with virtual models to understand its behaviors and used 3D rendering tools to bring it back to life in some way.
Previously, researchers couldn’t confirm whether Harpagornis acted like a golden eagle, hunting and killing its prey, or rather like a vulture, scavenging the meat and bones of already dead creatures. To find out, the authors of the new study distilled potential characteristics of ancient species from 3D images and compared them to characteristics of birds today.
The creature’s beak, skull, and talons were studied using geometric, morphometric and finite element analyzes, tools that enabled the team to determine the shape and strength of the features of the bird. They then calculated the pressure that those body parts could withstand to see if the eagle was strong enough to attack prey, or just strong enough to dig into the flesh of a carcass.
They found that the harpagornis’ beak and talons were more like that of an eagle and were able to withstand strong pressure, leading them to believe it was in fact a predator. . But the shape of his skull, which showed spots of tension while eating, indicated that once he had his meal, he would rip it apart and eat internal organs like a vulture. This combination of strategies also suggests that the species may have undergone rapid evolutionary changes to maximize its resources as a hunter and scavenger.
Haast’s Eagle is known to have consumed another extinct Pacific bird, the moa, based on preserved bones marked with talons. But this more recent discovery suggests that the raptors themselves slaughtered the some 400-pound beasts, then methodically plucked their guts out. Cave paintings from before the extinction of harpagornis suggest that the species was bald, much like vultures today.
When humans hunted moas to their extinction around 800 years ago, Haast’s Eagle also went extinct. While he’s no longer around to ram his head into massive carcasses, studies like this provide insight into how ancient predators found creative ways to survive.