For as long as scarab beetles have been rolling dung balls, they’ve had to contend with animal bandits tunneling into their precious pellets.  Paleontologists Victoria Sánchez and Jorge Genise of the Argentine Museum of Natural Sciences in Buenos Aires found at a site in Patagonia fossil dung balls that contain traces made by smaller scarab beetles, worms and bees that were apparently tapping into the nutrient-rich source. Dating to 45 million years ago, the tennis ball-size dung balls are the only fossilized evidence of ancient dung beetles in South America.  Back in those days, the region was a stomping ground for giant ground sloths and elephantlike creatures called gomphotheres that peppered the landscape with their mega-dung. Like their modern counterparts, these beetles rolled their bounty up as a food source for their larvae, and some of these balls turned to rock. Sánchez and Genise describe their findings in this month’s issue of Palaeontology.