Nearly two centuries ago, naturalists made crocodiles and tortoises walk over soft pie crust for science. The flour-dusted experiment was an attempt to capture the movement of an animal that had been dead for an incomprehensible amount of time.

The inspiration for the experiment, organized by Oxford University naturalist William Buckland one day in 1824, was a fossil trackway that had been discovered in the prehistoric sandstone of Corncockle Muir in Dumfriesshire, Scotland. The ancient, multi-toed, vaguely hand-shaped imprints had caught the attention of a Mr. Carruthers, who extricated the fossils and presented them to the Church of Scotland minister Henry Duncan. The reverend used the tracks to decorate his summerhouse, but he also created casts which he sent along to Buckland.

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