In 1993, on the picturesque island of Valentia, County Kerry, Ireland, an undergraduate geology student (Iwan Stossel) made the discovery of a lifetime. While examining rocks on the island's coast he came across a rock platform containing a set of ancient animal footprints. The tracks have since been dated to almost 400 million years ago and are regarded as among the earliest footprints known to science, and certainly the oldest known footprints in Europe.
A Long-lost Relative
Hundreds of millions of years ago, all vertebrate life existed in the seas. The oceans were filled with many different types of primitive fish-like creatures. Conditions on dry land were totally inhospitable. Then, little by little, life began to take hold above water. First came plants, then later came the first land animals. These creatures were the ancestors of most animals familiar to us today - all amphibians, reptiles, birds and mammals, including of course, humans themselves. What these animals looked like, what possessed them to leave the oceans, and how and why they evolved lungs to breathe air are all questions fundamental to the understanding of our planet and ourselves. Time has erased most traces of these first land creatures, so when evidence is uncovered its importance cannot be underestimated.
The Wet Concrete Effect
385 million years ago, most of Southern Ireland was part of a gigantic flood-plain near the equator, much the same as Bangladesh is today. Every so often, massive floods inundated the region, depositing large quantities of silt and sand. At one stage a four-legged animal1 walked across this silt as it was drying out. Its tracks were preserved, just as if it had walked across wet concrete. After further floodings and aeons of compaction, these footprints turned to stone, looking almost exactly the same as the day they were created. It was only in the last few thousand years that the tracks once again saw the light of day as a result of persistent erosion by the sea.
Footsteps in the Bedrock
The Trackway itself is on a coastal rock platform2, not far from the Valentia Lifeboat Station. The platform is relatively small - about the size of two car-park spaces. Imprinted on the rock are 150 distinct prints from at least one animal. Although no fossil skeletons have been found, the tracks provide strong indicators of the type of animal that made them. Between some of the prints is a distinct furrow, indicating that the animal's torso was low off the ground - comparable in shape perhaps to a large iguana. The animal itself was around the size of a small dog such as a cocker spaniel.
Looking into the Past
The Trackway site has been bought by the Irish Government and has already become a major site of scientific interest in Ireland. A viewing area for tourists is under development. For optimal views of the footprints it is best to view them in the early morning or late afternoon when the sun casts the prints into relief.