Chesil Beach, an extraordinary sea barrier, 29km long 200m wide and 16m high, looks like a gigantic man-made structure but it’s entirely natural. Fossil specimens from the area’s crumbling cliffs have transformed our understanding of natural history.
Thanks to Stephen Spielberg’s 1993 film, everybody has heard of the ‘Jurassic Period’. Named after France’s Jura Mountains, where ‘Jurassic limestone’ was first identified, it began 200 million years ago and lasted for 45 million more. Back then, the super-continent of Pangaea was breaking up, dinosaurs roamed the land and flying lizards ruled the skies. Our ancestors, the mammals, were tiny mouse-like creatures. Birds and flowering plants, yet to appear.
What is now the south of England was a tropical sea during the Jurassic. Molluscs and crustaceans abounded. There were shark-like fish and predatory marine reptiles, their remains becoming fossilised in the muddy sediments of the sea-bottom. Portland stone, destined to become the fabric of great buildings, was formed back then. Over millennia, the seabed became a huge filing cabinet, holding the fossilised records of countless ancient creatures. About 15 million years ago, seismic upheavals raised these ancient strata above the water. But the sea, wanting its former territory back, batters the coastal cliffs relentlessly. The Devon coast has been crumbling for centuries, laying bear sediments which experts can read like a book. On a fossil hunting expedition there last week, my grandchildren and I joined the enthusiasts, with their little hammers, cracking open rocks laid bare in recent landslides.
‘She sells sea shells on the sea shore’ may refer to ‘the princess of palaeontology’. Mary Anning, the daughter of a cabinet-maker and his wife, was born in 1799 at Lyme Regis on the Jurassic Coast. As an infant, she was one of four people struck by lightning. Three, including the woman holding her, were killed, but Mary survived. The lightning strike, it was said, transformed her personality.
Of the 10 Anning children, eight died in childhood. Their father had a ‘sideline’; harvesting fossils to sell to collectors. When Mary was 11 years old, he fell from a cliff and died soon afterwards, leaving his wife and family without a bread-winner. To earn money, Mary and her brother turned to fossil hunting, using the skills learned from their father. It was a dangerous activity; they had to work fast to remove fossils from newly exposed cliff-faces before further landslides carried them away. Mary narrowly escaped a rock-slide which killed her pet terrier.
Her ability to discern the faint outline of a fossil became legendary but Anning was no mere sniffer-dog. The fossil remains of a large creature usually come to light as disorganised fragments, a jigsaw-puzzle with key pieces missing. Mary possessed an uncanny instinct, a sixth sense which told her what each ancient creature might have looked like. Shortly after their father’s death, she and her brother came upon the remains of a crocodile with a 1.2m skull. Their discovery of an ichthyosaur created a sensation. This ‘fish lizard’ lived in the sea, its limbs partially transformed into fins. In 1823, she found a plesiosaur, the ‘near lizard’ which became the model for claimed Loch Ness monster sightings.
Though she had little formal education, Anning mastered the geological literature of her day. She ‘understood more of the science than anyone else in the kingdom’ said one commentator. Women were barred from membership of learned societies but some of the leading palaeontologists of the day visited and consulted Anning. Becoming a celebrity, she never lost her Dorset accent. A visit of London was the only occasion on which Mary left Lyme Regis. She died of breast cancer in 1847.
My grandchildren didn’t unearth an ichthyosaur but finding little ammonite fossils proved just as exciting.