A chance encounter, frozen in time

Object of the Month: 11/2007

What is it?:

Fossil animal tracks


near Grand Canyon, Arizona

Age: approx. 260 million years old
Accession #: SMM P92.3.1

Fossil animal tracks
Fossil animal tracks

A clear blue morning. A broad desert, blooming after a spring rain. Two creatures scamper across the sand. Are they hunting? Fleeing? Simply looking for shade? They meet briefly, shuffle their feet, and move on.

Years pass—260 million of them. The sand turns to stone. A scientist walking the south rim of the Grand Canyon finds the long-forgotten footprints. He identifies the large tracks on the left as belonging to a lizard-like animal called Laoporus (lay-OP-er-us). But he doesn’t recognize the prints on the right. He takes the rock back to The Science Museum, studies the tracks, and realizes they represent a new scorpion-like species, Permichnium coconinensis (per-MICK-nee-um co-co-nee-NEN-sis).

A bustling city. A cloudy November day. You stand in front of an exhibit case, staring at the fossil footprints, and imagining a chance meeting on a cool desert morning, so very long ago.