About ten years ago a friend came to visit with her children. Her son, aged about ten, started to rummage through the pile of fossils outside our back door. He picked up a big piece of rock stuffed full of lovely rhynchonellids – fossil brachiopods common in Jurassic rocks. I told him I’d found it in a field nearby and prattled on for a while about the wonders of fossils. But I could see there was something bothering him. Eventually he came out with a question: ‘How come there are seashells in that rock when we’re nowhere near the sea?’ (You need to know that I live nine miles from the coast.) I pushed the question back at him: ‘What do you think?’ He turned the question over once in his mind and then said ‘Is it because this field used to be covered by the sea?’
He was right of course and our 30-second conversation effectively covered the first 3,000 years of human thinking about fossils. In fact his question was an echo of Leonardo da Vinci, writing in 1508: ‘Why do we find the bones of great fishes and oysters and corals and various other shells and sea-snails on the high summits of mountains?’
In ancient times Chinese sages wondered if fossils found in mountains were birds that had been trapped and turned to stone, while fossil bones and teeth were surely evidence of dragons. But some Chinese writers argued that every so often the world went through huge changes, in which areas of land became sea. European Renaissance scholars found this hard to believe and preferred the idea that fossils were some sort of practice creations or signs from God that we needed to interpret.
Now we accept the startling truth that the earth is continually changing, and that we live in what is just the latest in a succession of worlds. So the fossils that we find on the Yorkshire coast are messengers from those other worlds bringing news of events from 180 million years ago. It’s one way of keeping up to date.