An amateur paleontologist has discovered the world’s smallest known fossil vertebrate footprints at the Joggins Fossil Cliffs, a 689 ha paleontological site along the coast of Nova Scotia.
Photograph and interpretive drawing of the footprints (adapted from Matt Stimson et al / Ichnos)
A fossil specimen of the ichnogenus Batrachichnus salamandroides was collected by local amateur paleontologist Gloria Melanson, daughter of Don Reid, the famed Keeper of the Joggins Cliffs, while walking the Joggins beach.
“This was one of the most exciting finds I have ever made and I am very pleased that, along with my colleagues, we are able to share it with the world. Every big fossil find is by chance; it’s all about being lucky and recognizing what you’re looking at. When I saw the very small tail and toes I knew we had something special. I never thought it would be the world’s smallest,” Melanson said.
The footprints, described in a paper in the journal Ichnos, belong to a small amphibian which would have roamed the Earth 315 million years ago, a creature not unlike a salamander.
The fossil record at Joggins is most famous for its diverse skeletal record of small tetrapods, dominated by an array of small, primitive amphibians, and the oldest known reptile, Hylonomus lyelli, entombed within once-hollow fossil tree stumps.
Small trackways of these animals at the site are common, but none so small as the one discovered recently.
The 48-mm-long trackway preserves approximately 30 footprints with the front feet measuring 1.6 mm long and back feet measuring 2.4 mm long. Professional paleontologists have confirmed that the trace maker was a juvenile amphibian, similar to a salamander with an estimated body length of only 8 mm from snout to tail.
Further examination shows the animal began in a walk and later changed direction as it began to run. Speculation could be made that these are some of the juvenile’s first footsteps on land after transforming from a tadpole stage that hatched in a local pond. The change in direction and speed may be interpreted as the animal either becoming startled by a larger predator, or perhaps while hunting some small insects, itself.
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Bibliographic information: Matt Stimson et al. 2012. The Smallest Known Tetrapod Footprints: Batrachichnus Salamandroides from the Carboniferous of Joggins, Nova Scotia, Canada. Ichnos: An International Journal for Plant and Animal Traces, volume 19, issue 3, pages 127-140; doi: 10.1080/10420940.2012.685206
