Imagine you are walking through a thick mass of poplar and pine trees, ferns and grasses brushing your legs, sunlight dappling the path before you. Bees and dragonflies buzz through the muggy air, humid after a fresh spring rain. Suddenly, you see movement through the trees ahead, and hear a low, moaning call being answered by a similar cry. As you push apart a curtain of Saskatoon bushes, you are stunned to see a life-sized Parasaurolophus hovering above you, protecting its young. It hollers at you to back off, shaking its head menacingly from side to side.