Introducing Pelagornis sandersi, an extinct giant bird that lived some 25 to 28 million years ago. With an estimated 24-foot (6.4 meters) wingspan, the enormous albatross-like creature is now considered the largest bird to have ever taken to the skies.
The giant seabird, which was twice the size of the Royal Albatross (the largest flying bird today), and larger than the previous record holder (the long-extinct Argentavis magnificens), was an extremely efficient glider. It featured long, slender wings that helped it stay aloft despite its enormous size.
Pelagornithids are an extinct group of birds known for bony tooth-like beak projections, large size, and highly modified wing bones. The well-preserved remains of this particular specimen were discovered near Charleston, South Carolina.
The math shows that P. sandersi was capable of flight. Its paper-thin hollow bones, stumpy legs, and giant wings would have made it a proficient flier, but an awkward land dweller. Mathematical models suggest that the creature reached the maximum body size possible for flying birds. Less clear, however, is how the thing actually managed to take off.
An artist's depiction of the new fossil species P. sandersi. Discovered bone fragments are shown in white. The well-preservered specimen consisted of multiple wing and leg bones and a complete skull. Credit: Liz Bradford.
To find out, Dan Ksepka of the National Evolutionary Synthesis Center in Durham, North Carolina, ran some simulations. It turns out that P. sandersi was too big to just flap its wings and launch itself into the air from a standstill. Rather, like Argentavis, it may have gotten off the ground by running downhill into a headwind, or taking advantage of air gusts to get aloft, similar to a hang glider.
Then, once airborne, the bird's long, slender wings converted it into an efficient glider. It likely rode along air currents that rose up from the Earth's surface, soaring for miles over the open ocean without having to flap its enormous wings. When hungry, it would swoop down to the water to feed on soft-bodied prey like squid and eels.
Read the entire study at PNAS: "Flight performance of the largest volant bird".
Image: Liz Bradford.