The Isle of Skye in Scotland, which was under an ice sheet during the last ice age, is not the first place you’d expect to find dinosaur fossils. At Staffin Beach in the northern part of the island lies a very rare instance of fossil footprints. While there are plenty of fossil bones and shells in sediments, it is unusual for footprints to be preserved because they are usually quickly eroded away by wind or water. In this instance, sediment must have been gently washed or blown over the footprints and the site must have been slowly sinking to remove it from the reach of the eroding elements. Footprints provide a rare window into the past. They provide insight into the gait of the animal and the flesh on the foot and even whether it was walking or running at the time.
The footprints were made in the middle part of the Jurassic period, about 165 million years ago. This part of Skye would have had a beach-like environment with waves or floods capable of transporting sand. The geological unit is a similar age to the Inferior Oolite in a previous post at the other end of the country. At the time, the British Isles was almost completely underwater. Scotland and northern England were part of an island chain that extended across into northern Germany and the Netherlands. Central and southern England were under a shallow sea during much of the Jurassic.
The footprints were made by a large 3-toed dinosaur, perhaps a Megalosaurus, a carnivorous dinosaur up to 7 m long that walked only on its back legs. Meaning “great lizard” from its Greek roots, this was the first dinosaur to be validly named. It was also one of the three types used to define Dinosauria (“terrible lizards”) later by Richard Owen. Megalosaurus was described by William Buckland in 1824, then Professor of Geology at the University of Oxford. It was subsequently given the species name Megalosaurus bucklandii in his honour. As one of the first professors of the new field of Geology, Buckland struggled with prevailing mythical explanations for the Earth’s surface against mounting evidence that the Earth had existed for an enormous amount of time. He advocated a theory called catastrophism which proposed the Earth’s surface was created through a series of short-lived Earth-shaping events.
Buckland was a careful scientist and was one of the first to document an ice age palaeontological site, located at Kirkdale Cave in Yorkshire. Here he recognised a hyena den where the inhabitants had dragged in bones from elephants, hippopotamuses, rhinoceroses, bison and deer among others. African fauna in the North York Moors is a powerful example of climate change in the recent past. Although he thought the site had been sealed off by a great flood, he later abandoned this explanation and championed the idea of extensive glaciation across the British Isles instead. Modern geology now recognises that the Earth’s surface was shaped slowly through time, occasionally punctuated by relatively brief local catastrophic events.
I blame my interest in dinosaurs (and passion for recycling!) on the first book I can remember reading as a 4 year old, called Dinosaurs and all that rubbish. The book was born out of the post-space race environmental movement of the 1970s. It is a fable about sacrificing the natural world in the pursuit of technology and development. After watching Life on Earth in 1979 I was fascinated by natural history and wanted to be a scientist. I subsequently did a degree in Palaeontology and some micropalaeontology in my PhD. After a post-doctoral fellowship in micropalaeontology I realised that there are very few jobs for palaeontologists so I specialised in climate change instead. Having seen these fossil footprints on a field trip to Skye to look at glacial geomorphology, I wanted to record their shape in 3D. Recently, a clueless tourist attempted to make a 3D cast of the print with plaster which resulted in some damage. Elsewhere in the world, thieves have cut footprints out of the rock with saws. It occurred to me that by making a 3D model, people could enjoy the prints without feeling the need to “own” them. The model above can be enjoyed in virtual reality or by printing a scale copy using a 3D printer. Fossil footprints are a valuable reminder of the passage of time and of changing climate, and should be left alone to inform and inspire the next generation of scientists.