Therizinosaurus vs. Psittacosaurus
70 million years ago in Late Cretaceous Mongolia, a forest covered land is interspersed with river channels, mudflats, and shallow lakes. Tall conifers and diverse assemblages of understory plants create a dense forest habitat.
A storm has swept through the night before, bringing a deluge of rain and winds that shook the trees violently. In the early morning light, Psittacosaurus scampers his way through the sodden understory, navigating around the wreckage of newly broken tree limbs and overturned roots. While this is not the forest of his home, miles away and 30 million years in the past, Psittacosaurus is well camouflaged to avoid the gaze of predators in the low forest light (Vinther et al., 2016). Psittacosaurus is foraging industriously, hoping to find a particularly tasty morsel that might have been uncovered by the storm.
Meanwhile, Therizinosaurus is also taking advantage of the cool dawn. At 10 meters in height and 3 tons, the herbivorous giant can use his height and extensive reach to access high strata vegetation.
This particular morning, Therizinosaurus has found a tree that, toppled by the storm, has become snagged in the branches of a standing tree. The branches of the overturned tree are still too high off the ground for most herbivores to get at, but Therizinosaurus is able to hook the foliage on his record-breakingly long claws and pull downwards (Lautenschlager, 2014).
Unbeknownst to Therizinosaurus, his vigorous pulling motions are shaking seed pods out of the branches and onto the forest floor. As the pods strike the ground, they bounce and roll off into the underbrush in all directions. Psittacosaurus, spying an opportunity, skitters closer to snatch up a seed pod.
In that moment, the branches of the standing tree, strained beyond capacity by the combined weight of the toppled tree and Therizinosaurus’s powerful pulls, give way with a groan and a crack.
The trunk of the toppled tree plummets downwards, missing Therizinosaurus by inches.
Psittacosaurus is not so lucky.
The trunk of the tree falls perpendicular across the animals back. A larger animal might have survived such a blow, but the spine of the 2m long Psittacosaurus breaks almost instantly.
By accident and good fortune,