By Tim Binnall
Researchers in Australia have identified a heretofore-undiscovered species of ancient eagle that was likely a fearsome apex predator of its day. The remarkable raptor, reportedly given the scientific name Archaehierax sylvestris, is believed to have roamed the skies of southern Australia around 25 million years ago. Boasting a nearly six-inch-long foot span, the bird would have been able to prey on larger creatures such as the ancestors of modern-day koalas and possums as well as birds living in a lake near where the fossils were found. "The largest marsupial predators at the time were about the size of a small dog or large cat, so Archaehierax was certainly ruling the roost," said paleontologist Ellen Mather, who co-authored the paper detailing the discovery.
The discovery is particularly noteworthy, co-author paleozoologist Trevor Worthy explained, because eagle fossils are fairly rare by virtue of the predatory birds being "at the top of the food chain" and, as such, unearthing just one bone from such an ancient bird would be considered a fantastic find. However, with the Archaehierax, researchers were about to recover nearly the whole skeleton, which Worthy described as "pretty exciting, especially considering how old it is." He went on to marvel that "I have studied this system for many years now and this is the most exquisite fossil we have found to date."
By studying those remains, Mather and Worthy were able to formulate some theories about how the creature may have lived when it once resided in the region. The Archaehierax, they said, possessed short wings similar to predatory birds that live in the forests of the planet today, but it also sported long legs that allowed for "considerable reach." By virtue of these two characteristics, Mather said, the ancient eagle was probably "an agile but not particularly fast flier and was most likely an ambush hunter. It was one of the top terrestrial predators of the late Oligocene, swooping upon birds and mammals that lived at the time."