Ancient 'Saranwrap' Preserves Fossils

Why are some fossils preserved so beautifully? Dr Jan Zalasiewicz of the University of Leicester Department of Geology believes it is because they were wrapped in a sort of clingfilm, hundreds of millions of years ago. He, together with Helen Jones, a Leicester undergraduate and Professor Barrie Rickards of Cambridge University, have been puzzling over why some graptolites (pictured below) – extinct, ocean-going animals ? are so curiously preserved.