Frog Evolution May Be Explained By Newly Discovered 270 Million-Year-Old Amphibian Species

Findings of amphibian species that date back 270 million years could help to explain the evolution of frogs.

A new ancient amphibian species found by scientists may help to fill in the gaps in our knowledge of the evolution of salamanders and frogs today.

First discovered in a Texas rock formation in 1984, the fossilized skull of the 270 million-year-old frog progenitor was discovered. But instead, it sat in a collection at the National Museum of Natural History of the Smithsonian Institution for decades, waiting to be examined.

Finally, in 2021, a team at the Smithsonian started analyzing the relic to identify the prehistoric animal to whom it belonged. The results were released on Thursday in the Linnean Society’s Zoological Journal.

The new species has been jokingly called Kermitops gratus by paleontologists in remembrance of Jim Henson’s Kermit the Frog.

The lead author of the research, Calvin So, a doctorate student at George Washington University, noted that naming the creature after the well-known figure is also a way to get the public interested about the finding.

“Using the name Kermit has significant implications for how we can bridge the science that is done by paleontologists in museums to the general public,” he stated in a press statement. “Because this animal is a distant relative of today’s amphibians, and Kermit is a modern-day amphibian icon, it was the perfect name for it.”

The fossil, according to researchers, was a form of temnospondyl, an extinct amphibian that mostly existed in the Carboniferous, Permian, and Triassic periods and lived more than 200 million years ago.

Scientists have determined that the one-inch-long fossil possesses numerous distinctive features that set it apart from other species that have been found. Its eyes are huge and oval-shaped, and its snout is long and curled, yet its skull has a small area behind the eyes.

Given its head shape, it is likely that the animal consumed small insects, such as salamanders and frogs, as well as grubs, which are the larval form of some species of beetles.

There are some distinctions between modern amphibians and Kermitops. The palpebral bones, or eyelid bones, of the skull were found by the scientists. A nictitating membrane, a third eyelid that lubricates and protects, is present in amphibians along with movable eyelids.

Furthermore, dental evidence was discovered, albeit not in the same location as contemporary frogs, the majority of which have little teeth on their upper jaws and roof of their mouths.

The Smithsonian researchers noted that because amphibians have small, delicate bones, the history of amphibians and their progenitors as recorded in fossils is “fragmentary,” making it difficult to analyze the evolution of these animals to their present counterparts. On the other hand, the discovery of Kermitops may provide some insight into the evolutionary process.

“Kermitops offers us clues to bridge this huge fossil gap and start to see how frogs and salamanders developed these really specialized traits,” he added.