This sandstone slab contains trackways of two animals: a lizard-like Laoporus and a scorpion-like Permichnium. The tracks were made about 260 million years ago on sand dune hills near the south rim of today’s Grand Canyon in northern Arizona. The trackways present an intriguing problem as to what took place when the track makers met and “scuffle prints” resulted.

The challenge here is to reconstruct the behavior of the two different animals. Were they walking, running, to avoid danger, in pursuit of a meal? Most paleontologists would agree that only Sherlock Holmes could provide a totally correct solution to this case.
– Bruce Erickson, Fitzpatrick Chair of Paleontology