Friday 7 January 2022

DENDRERPETON FROM THE JOGGINS FOSSIL CLIFFS

Dendrerpeton acadianum, an extinct amphibian
One of the best Canadian fossil finds stems from a random boulder picked up on the beach near the town of Joggins, Nova Scotia. Inside were the bones of a fully articulated skeleton of Dendrerpeton acadianum, a Temnospondyli from the Lower Pennsylvanian. 

These little cuties belong to an extinct genus of amphibians who loved wet, swampy wetlands similar to those we find in the bayous of Mississippi today.   

Dendrerpeton is the primitive sister-group to a clade of Temnospondyls that includes Trimerorhachoids, the Eryopoids — Ervops, Parioxys, & Sclerocephalus — Zatracheids & Dissorophoids. 

This little guy along with finding the first true reptile, Hylonomus lyelli, ancestor of all dinosaurs that would rule the Earth 100 million years later serve as the reference point where animals finally broke free of the water to live on land. This evolutionary milestone recorded at Joggins remains pivotal to understanding the origins of all vertebrate life on land, including our own species. 

Joggins records life in a once a wet, swampy wetland
Sir Charles Lyell, the author of Principles of Geology, first noted the exceptional natural heritage value of the Joggins Fossil Cliffs. He described them as: 

“...the finest example in the world of a natural exposure in a continuous section ten miles long, occurs in the sea cliffs bordering a branch of the Bay of Fundy in Nova Scotia.” 

Indeed, the world-famous Bay of Fundy with its impressive tides, the highest in the world, and stormy nature exposed much of this outcrop.