Studying dinosaur bones and physiology can only teach us so much about how dinosaurs actually walked the Earth. Because dinosaurs called theropods are related to modern birds, a few researchers thought they could study how they walk using chickens.
Theropods include dinosaurs like the Tyrannosaurus and Velociraptor, but they also ranged in size all the way down to tiny chicken-sized raptors covered in feathers. Theropods and modern birds also both have spongy air-filled bones, wishbones, and feathers and lay eggs and watch over them.
Theropods first appeared during the late Triassic period about 230 million years ago. During the Jurassic, birds evolved from ancient theropods, and today are represented by 9,900 living species.
To make chickens change their gait, the researchers added a tail, which looks surprisingly like a toilet plunger, to their butts. This changed their center of gravity, and made them walk differently.
You can see the difference below:
Here's how a chicken walks normally, without the "tail:"
And here's one walking like a dinosaur, with his "tail:"The finding?
"Our results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution," the researchers write in the study, published in the open-access journal PLoS ONE.