Homalocephale vs. Dryosaurus
Time Period & Environment: Late Cretaceous Nemegt Formation of Mongolia, araucarian conifer forest
Written By: Caitlin Lindblad
The herd of long-necked titanosaurs, some of the largest animals to ever to live on land, hadn’t moved from the clearing at the edge of the river all morning. The adults, who were nearly 20 metres long (longer than two school buses) had been lumbering back and forth from the water to the forest’s edge, reaching with their impossibly long necks to munch at the highest branches. Weighing nearly 13 tons, the animals have to eat almost constantly.
The Giganotosaurus has been watching them for hours from her concealed vantage point. Though the size of T. rex, the dense foliage, and her striped green and gold skin camouflage her well. She has spotted what she had hoped to find here; weaving between the legs of the adults, still small enough to gamble along like a little elephant, is a baby titanosaur. Her favorite food.
Neither the Giganotosaurus, who weighs an estimated eight tons, nor the titanosaurs are capable of running. They are just too big. Instead, the titanosaurs rely on their immense size to divert predators, although their young remain vulnerable. The Giganotosaurus is a skilled ambush predator and can walk many hundred of kilometres at a time, searching for the next opportunity. Just like this one.
Suddenly, one of the adult titanosaurs lets out a deep, almost subsonic bellow. Others in the herd take up the alarm call, moving as fast as they are able towards the waters edge, the adults forming a protective circle around the baby and juveniles.
Startled, the Giganotosaurus looks over to see another theropod charging out of the undergrowth towards the heard. This animal, an Aucasaurus, is half the size of the Giganotosaurus but seems just as hungry. Though both are from Argentina, the Aucasaurus is from a later time period than the Giganotosaurus. He is not used to these long-necked giants and has no skill in hunting them. Like his close relative, the Carnotaurus, he is used to hunting much smaller prey.
The titanosaurs bellow, making the air and the ground vibrate as if someone has turned a super-woofer up as loud as it will go. The Aucasaurus pulls up short, as if suddenly deciding this was not such a good idea after all. When an adult titanosaur makes to charge (although in slow motion, a titanosaur charge is terrifying), the Aucasaurus turns to flee – straight towards the Giganotosaurus’ concealed hiding place.
The Aucasaurus doesn’t even have a chance. Hit with the force of an ongoing freight train, the smaller theropod is knocked to the ground, and then the Giganotosaurus is on him slicing, tearing, ripping. It’s not the baby titanosaur she’d hoped for, but this meal will satisfy her for a while.