New research found that American alligators have remained untouched by evolutionary change for around 8 million years or up to 6 million years older than previously thought.
Dr. Evan Whiting, lead researcher from the University of Minnesota, said, “If we could step back in time 8 million years, you’d basically see the same animal crawling around then as you would see today in the Southeast. Even 30 million years ago, they didn’t look much different. We were surprised to find fossil alligators from this deep in time that actually belong to the living species, rather than an extinct one.”
Dr. Whiting and his colleagues find the alligator as a survivor
which has withstand climate’s extreme changes and sea-level fluctuations which often caused animals that are less adaptive to go extinct or change quickly.
The scientists started rethinking about the alligator’s history after Dr. Whiting investigated a skull said to be from an ancient alligator discovered in Marion County, Florida which was thought to be extinct. They found out that the skull was identical to modern alligators.
They also studied the oxygen and carbon compositions of the ancient alligators’ teeth and the extinct crocodile said to be 20 to 25 feet in length named Gavialosuchus Americanus
that once ruled the Florida coastline but died 5 million years ago.
Dr. Whiting said, “the presence of alligator and Gavialosuchus
fossils at several localities in north Florida suggest the two species may have coexisted in places near the coast.”
The teeth analysis suggests
that Gavialosuchus Americanus was a marine reptile that seeks prey in the ocean while alligators hunt in freshwater and on land.
Dr. David Steadman, co-author from the Florida Museum of Natural History at the University of Florida said, “The gators we see today do not really compete with anything, but millions of years ago it was not only competing with another type of crocodilian, it was competing with a much larger one. The presence of the ancient crocodile in Florida may have helped keep the alligators in freshwater habitats, though it appears alligators have always been most comfortable in freshwater."
"While modern alligators do look prehistoric as they bake on sandbars along the Suwannee River or stroll down sidewalks on the UF campus, they are not somehow immune to evolution. The group they belong to, Crocodylia, has been around for at least 84 million years and has diverse ancestors dating as far back as the Triassic, more than 200 million years ago,” the group said.