Powerful jaws and bone-crushing bites have long shaped the popular image of Tyrannosaurus rex. Its feet, not so much. A new biomechanical study suggests that the giant predator did not lumber around flat-footed. Instead, it likely moved on the front part of its feet, in a bird-like, tiptoe-style gait that may have helped it stay faster and steadier than many reconstructions suggest. The work, published in Royal Society Open Science and led by researchers at the College of the Atlantic in Maine, argues that this detail could change how scientists model the animal’s movement, and how museums and filmmakers depict it. The question sounds small at first. Which part of the foot hit the ground first? But for a predator weighing more than 10 tonnes, that detail could shape speed, balance and the stress placed on the legs with every step. Size comparison between T. rex and several extant terrestrial vertebrates. (CREDIT: Royal Society Open Science) To test it, the researchers examined four well-preserved T. rex specimens: MOR 555, FMNH PR 2081, the former BHI …