UF Scientist’s Discovery Challenges Assumptions About Killer Bird

June 5, 1996

GAINESVILLE — Scientists are searching for more fossils after a University of Florida paleontologist discovered a wing bone that revealed a 2-million-year-old killer bird so tough that it survived the collision of two continents.

The wing bone, found three years ago in north central Florida’s Santa Fe River, reveals a lethal creature that was bigger and faster than a professional football linebacker, says Bob Chandler, a UF paleontologist.

“These were the most dangerous birds to have ever lived,” Chandler said. “They were probably heirs to the dinosaurs in that they were able to kill as efficiently as some of the larger meat-eating dinosaurs could.”

Now Chandler and his team are searching for more skeletal remains in the river, with the ultimate goal of putting together a complete skeleton of the prehistoric bird.

Called Titanus walleri, the bird was even larger than its notorious South American relative, the 5-foot tall and 150-pound Andalgalornis, which had a skull longer than that of a horse and a beak that could slice through bone, he said.

Chandler said Titanus walleri was the only flightless bird to survive the deadly collision of North and South America that formed the Panamanian land bridge 3 million years ago.

Although Andalgalornis has been the subject of intensive fossil expeditions by American scientists in the Argentinan badlands during the past 70 years, no one had ever found a wing bone, he said.

But when Chandler found the wing bone during a Florida scuba dive, the discovery revealed new information about the anatomy of these killer birds and challenged traditional ideas about how they lived.

Scientists knew the bird’s common ancestor flew, like other birds. But in studying the skeleton of Titanus walleri, Chandler found the upper wing bones were incapable of tucking beneath the lower bones, a feat necessary for the bird to fold its wings and fly. The creature probably didn’t need to fly and likely used its wings to hold and manipulate prey, he said.

“Like ostriches, this bird sacrificed the ability to fly in order to become a more efficient killer,” Chandler said. “It was so fast it could run at least 40 miles an hour.”

After drastic changes in climate and vegetation that came with creation of the Panamanian land bridge, Andalgalornis eventually disappeared from South America. Some scientists blame its extinction on competition from animals that migrated from the north, others on lack of food resulting from prey being unable to adapt to the new environment and dying off, Chandler said.

But its close relative, Titanus walleri, managed to survive over the short-term by crossing the land bridge to North America, only to eventually become extinct itself.

Titanus walleri was named for the late Ben Waller, an amateur paleontologist who started uncovering a treasure trove of fossils in the Santa Fe River in the 1960s. An amateur again played a role in 1993 when, diving with Chandler at a sinkhole within the river, Janis Brown found the wing bone, which Chandler identified. The sinkhole had at one time trapped some of these birds, turning them to fossils, he said.

While living in what is now Florida about 1.8 million to 2.4 million years ago, Titanus walleri shared the savannah-like landscape with camel, ground sloths, three-toed horses and giant armadillos.

Chandler, who is continuing expeditions in the Santa Fe River, said there is still much to learn about these birds, which have captured scientists’ imagination for decades. “Even though they’ve been around for 25 million years, both in North and South America, we don’t have extensive collections of any of these species yet,” he said.