Kermit the Frog inspires new 270-million-year-old species

Kermit has never looked cuter.

The fossilised skull of a 270-million-year-old ancient amphibian has been uncovered by scientists – who have named it after Kermit the frog. 

The team, from George Washington University (GWU), discovered the new species of proto-amphibian, or primitive amphibian, not in the field, but in a museum.

They have now christened it Kermitops gratus, in honour of the iconic Muppet. 

Lead author Calvin So, a doctoral student. said choosing the name created an opportunity to get people excited about discoveries scientists make using museum collections. 

The fossil currently sits in the Smithsonian’s National Museum of Natural History.

‘Using the name Kermit has significant implications for how we can bridge the science that is done by palaeontologists in museums to the general public,’ Mr So said. 

‘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 skull is around an inch long and has large, oval eye sockets. 

It was first unearthed by the late palaeontologist Dr Nicholas Hotton III after he spent years excavating fossils from rock outcrops in an area of north central Texas known as the Red Beds. 

The area’s rust-coloured rocks date back to the early Permian period more than 270 million years ago, and contain the fossilized remains of ancient reptiles, amphibians and sail-backed synapsids, the precursors to modern mammals.

His team collected so many fossils they could not study them all in detail, and the skull, a small proto-amphibian found in the Clear Fork Formation in 1984, has spent years waiting for attention. 

But in 2021, Dr Arjan Mann, a postdoctoral palaeontologist at the museum, finally took a closer look. 

‘One fossil immediately jumped out at me – this really well preserved, mostly prepared skull,’ said Dr Mann, who is a co-author on the new paper.

The skull has a cartoonishly wide-eyed face, and an array of traits from different features seen in skulls of other ancient ancestors of amphibians and living four-legged vertebrates.

They found that the region of the skull behind the animal’s eyes was much shorter than its elongated, curved snout, meaning the animal may have resembled a stout salamander, and snapped up tiny grub-like insects.

As the animal’s skull had so many unique features, the scientists concluded it belonged to a new genus – one now called it Kermitops, derived from a mashup of the words ‘Kermit’ and the Greek suffix ‘-ops,’ which means face. The species name ‘gratus’ is to show thanks, or gratitude, for Dr Hotton and his team who originally unearthed the fossil. 

Kermitops also helps reveal more about the early branches of the amphibian family tree.

Mr So said: ‘Kermitops offers us clues to bridge this huge fossil gap and start to see how frogs and salamanders developed these really specialized traits.’

Dr Mann hopes this discovery will inspire other palaeontologists to take a closer look at their own museum’s fossil collections.

‘This is an active area of research that a lot more palaeontologists need to dive back into,’ he said.

‘Paleontology is always more than just dinosaurs, and there are lots of cool evolutionary stories and mysteries still waiting to be answered. We just need to keep looking.’

The new project is the latest example of the Smithsonian’s history of collaboration with George Washington University.

The paper is published in the Zoological Journal of the Linnean Society.