GAINESVILLE --- Out of the mouths of long-dead animals come stories of vanished landscapes, ancient weather and the way the creatures lived and died.
With a unique combination of two scientific techniques, UF paleontologist Bruce MacFadden and colleagues analyzed fossilized horse teeth to see what the animals ate, and in doing so reconstructed Florida's environment as it existed 5 million years ago.
MacFadden's article in this week's issue of the journal Science describes how he analyzed ratios of carbon isotopes along with the scratches and pits in the fossilized teeth found in Lakeland phosphate mines. He concluded that the horses ate a combination of foods befitting an ancient Florida of savannah-like grasslands interspersed with lush forests and marshy wetlands inhabited by rhinos, llamas, elephants and other exotic creatures.
"This study is noteworthy because it's the first to be published that looks at the combination of these two techniques to understand ancient diets and the ecology of a particular group of extinct mammals," he said. "These techniques are revolutionizing our ability to understand what prehistoric animals ate. Before now, the only way we could figure that out was by looking at their teeth. Not only that, our research challenges the traditional view that the form and structure of the teeth alone can tell you something about diet."
Modern grazers such as horses and zebras develop elongated (high-crowned) teeth because they eat gritty, abrasive grasses, while browsers such as deer, whose diet consists mainly of soft leafy vegetation, have short teeth, MacFadden said.
But MacFadden's research on six species of prehistoric horses that lived
5 million years ago shows that despite all the horses having elongated teeth,
they were a combination of browsers, grazers and mixed feeders. "This is the
first time we've been able to use other techniques to challenge this assertion
Contact: Cathy Keen
University of Florida