A University of Florida-led study has determined that Titanis walleri, a prehistoric 7-foot-tall flightless “terror bird,” arrived in North America from South America long before a land bridge connected the two continents.
UF paleontologist Bruce MacFadden said his team used an established geochemical technique that analyzes rare earth elements in a new application to revise the ages of terror bird fossils in Texas and Florida, the only places in North America where the species has been found. Rare earth elements are a group of naturally occurring metallic elements that share similar chemical and physical properties.
“It was previously thought that Titanis immigrated to Texas across the Panamanian land bridge that formed about 3 million years ago connecting North and South America,” said MacFadden, a curator of vertebrate paleontology at the Florida Museum of Natural History at UF. “But the rare earth element analysis of a fossil Titanis bone from Texas determines its age to be 5 million years old. This shows that the bird arrived 2 million years before the land bridge formed, probably across islands that formed what today is the Isthmus of Panama.”
Thanx to James for pointing it out to me.
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