What is a Frogamander?

The word frogamander was coined by University of Calgary comparative biologist, Jason Anderson, to describe a fossil thought to show an evolutionary link between frogs and salamanders. The fossil is 290 million years old and was found in Texas in 1995 by a field study group associated with the Smithsonian Institution. The discovery of the frogamander fossil suggests that frogs and salamanders share an ancestor.

The frogamander fossil shows a skull that resembles a frog's, but fused ankle bones that only salamanders have. The backbone is said to reflect a combination of a frog and a salamander spine. The frogamander fossil shows that the creature died on its back. The 290 million year old fossil provides evidence of the long disputed missing link between extinct and modern frogs and salamanders.

Anderson named the frogamander fossil, Gerobatrachus hottoni after one of the Smithsonian field group members that found the fossil in 1995 in Texas. The name means Hotton's elderly frog. Anderson notes that the fossil was in Nicholas Hotton's pocket with a piece of paper containing the word, Froggie on it. According to Anderson, the note indicates that Hotton did understand what the fossil actually was.

Anderson's team at the Faculty of Veterinary Medicine at the University of Calgary in Alberta, Canada, took many hours to remove layers of rocks to reveal the entire skeleton. This was done years after the 1995 discovery and Anderson and his team were the first to work on the frogamander fossil. The fossil turned out to be nearly complete in its visible impression of the frogamander creature.

One ongoing argument in the scientific community was that modern salamanders and frogs did not evolve from an ancient amphibian species. The discovery of the 290 million year old frogamander fossil has put that argument to rest. Thanks to the proven existence of Gerobatrachus hottoni, we now know that some modern salamanders and frogs evolved from the ancient amphibian group, temnospondyls.

A Frogamander refers to an extinct amphibian that exhibits a blend of characteristics from both frogs and salamanders. This term is often used to describe Gerobatrachus hottoni, a fossil species that lived about 290 million years ago and is considered a transitional form in the evolution of modern amphibians.

Frogamanders like Gerobatrachus hottoni existed during the Late Permian period, roughly 290 million years ago. Paleontologists have studied fossilized remains to understand their anatomy and place in the evolutionary tree. These fossils provide crucial insights into the early diversification of amphibians.

Frogamanders possessed a combination of features: they had a wide, frog-like skull and a salamander-like body structure. Their ear structure was similar to that of modern frogs, while their vertebrae resembled those of salamanders. This unique blend of traits indicates their transitional evolutionary status.

Frogamanders are significant because they represent a key evolutionary link between primitive amphibians and the two main modern groups, Anura (frogs and toads) and Caudata (salamanders). Their existence supports the theory of a shared common ancestor and helps scientists understand the sequence of evolutionary events.

Frogamander fossils have been discovered in North America, with the most notable specimen, Gerobatrachus hottoni, unearthed in Texas. These fossils reveal a fascinating mix of anatomical features that bridge the gap between two distinct amphibian lineages, shedding light on the evolutionary history of these animals.

While there are no direct descendants of Frogamanders, modern frogs and salamanders are considered their distant relatives. The evolutionary branch that led to Frogamanders diverged, giving rise to the diverse array of amphibian species we see today, each adapted to their unique ecological niches.