STORY: Animal tracks in a river bed in the US state of Texas. Not too unusual, one would think, but these are 113 million years old. They come from dinosaurs that once inhabited the area around present-day Glen Rose. The ongoing drought in Texas has exposed the fossil footprints. At first glance, they look like T-Rex tracks. But they actually belong to a dinosaur called Acrocanthosaurus, as Jeff Davis, director of Dinosaur Valley State Park, explains. “It was a two-legged, carnivorous animal with small arms that was very similar to the Tyrannosaurus Rex, only a little smaller. But it was still a fairly large creature, weighing around seven tons. So it wasn’t a small critter, for sure. They ran through the chalky mud bottom at the edge of the ocean that ran through what is now the United States during the Cretaceous period.” Today, no ocean covers the tracks, but the Paluxy River – at least usually. The currently dried up river also played a role in the discovery of the footprints. “For over a hundred million years they were protected and preserved by these layers of sediment and rock. And then the river dug through those layers and exposed the tracks. So it’s kind of a double-edged sword because without the river we wouldn’t see them We didn’t know they were there. But once they’re uncovered, they start to break down. Like any other rock, they break down over time through weathering and erosion.” Wind and glowing sun or flowing water – without protective sediment, the ravages of time will gnaw at the fossil treasure. But for the time being, Jeff Davis and visitors to the park can enjoy it.