Humans aren’t the only ones that can walk on two legs; it’s a talent shared by birds, monkeys, and even dinosaurs. And given the wealth of research that proves the close evolutionary relationship between dinosaurs and birds, researchers decided to take advantage of this fact and use bipedal quails to shed some light on dinosaur gait.
Though birds indeed use their two tiny legs to move forward, “they use a completely different technique from us humans,” lead author Dr. Emanuel Andrada noted in a statement.
As it turns out, quails and other birds alike use the so-called “grounded running” style when they move quickly, in which at least one leg is always touching the ground. But unlike human beings, who walk in an upright position with the body’s center of gravity directly above the legs, bird bodies are horizontally forward-facing. This awkward stance puts their center of gravity in front of their legs rather than above them, forcing birds to constantly self-correct.
“The animals have to constantly balance out their own bodies in order to prevent falling forwards,” explained researcher Dr. Reinhard Blickhan.
High speed X-rays were able to monitor the exhaustive movements of quails while running, and showed that their ground running style is extremely energy consuming. However, for birds this effort is necessary and entirely worth it to keep from falling flat on their face.
“This apparent wasting of energy is the price for a very stable posture during locomotion, especially on an uneven terrain,” Blickhan said.
It is no secret that dinosaurs led to the rapid rise of birds, and so the team from Jena University in Germany hopes that their insight into bipedal birds can reveal a bit more about dinosaur gait. The famous and feared Tyrannosaurus rex was a bipedal dinosaur, and the new findings indicate that it and other two-legged sprinters may have implemented a ground running style as well, constantly facing forward while hunting for their next meal.
“It is not clear yet how two-legged species like Allosaurus or Tyrannosaurus Rex really moved forward,” Andrada added, but scientists are getting closer.