The print in the stone
On June 1, 1968, amateur fossil collector William J. Meister was hunting for trilobites with his family near Antelope Springs, Utah. Splitting open a two-inch-thick slab of rock, he found something unexpected. Inside the stone was what appeared to be the print of a sandal, about 10.25 inches long and 3.5 inches wide. Within this shoe-like outline, and seemingly crushed by it, were the fossils of two trilobites.
The rock layer belonged to the Wheeler Formation, a deposit of Middle Cambrian shale and limestone known for its many trilobite fossils. Geologists date this formation to over 500 million years ago. The discovery presented an immediate conflict with the geological timescale. Modern humans, and their footwear, did not appear until hundreds of millions of years after trilobites went extinct. The "Meister Print," as it became known, was quickly publicized by creationists as evidence against evolution. One early proponent, Melvin A. Cook, a metallurgist, promoted the find as an authentic human artifact from the deep past. In the following weeks and months, other individuals reported finding similar sandal-like marks and even what they described as the footprints of a barefoot child in the same area.
A trick of geology
Scientists, however, remained unconvinced. Geologists and paleontologists who examined the specimen concluded that it was not a footprint at all. They identified the shoe-like shape as a common geological phenomenon known as spalling. This occurs when slabs of rock break away from a larger piece, sometimes in curved, oblong patterns that can coincidentally resemble familiar shapes. The rock of the Wheeler Formation is particularly prone to this type of fracturing.
Detailed analysis of the Meister Print revealed none of the key features of a genuine footprint. There was no evidence of pressure deformation in the rock, no displacement rim created by a foot pushing into mud, and no signs of a natural striding sequence. The supposed "heel" was simply part of a crack that extended beyond the boundary of the print-like shape. The trilobites within the shape were real, but their presence is not unusual in the fossil-rich Wheeler Shale, where they can be found in high concentrations. The human brain's tendency to see familiar patterns in random arrangements, a psychological phenomenon called pareidolia, explains why the spalled rock fragment was interpreted as a footprint. Geologists have found many similar concretionary slabs and spall patterns in the Antelope Springs area that bear a superficial resemblance to footprints.