 The Tyrannosaur has been a fascination in the public's eye, literally because it's larger than life. It's one of the largest predators ever to walk the earth. And as far as we know, they're probably among the hardest-biting predators ever to live. But one thing we don't know as well is how they grew to become that fierce predator. The interest in juvenile Tyrannosaurs came about because there's been previous comparisons made between this predator and hyenas, which are my first love in fossils. During the time that the Tyrannosaurus rex lived, there was a food web that looked very different from today's. There was this large predator that dominated the landscape. Studying the bite force of juveniles and also in conjunction with the adults, we could begin to understand how those predators interacted with your prey. And that in turn helps us understand better the entire environment before the time of the mammals. In our experiment, we did several cow bones with a model of a T-rex tooth. And we found that a 12 to 13-year-old T-rex was able to bite with more than 10 times the force that a comparable teenage human can bite with. And we use cow bones because the thickness of the cow bones are similar to what some of these fossil dinosaurs may have had. After dozens of experiments, now biting on cow bones, what we found was that juvenile T-rex could bite up to more than two times the bite force compared to previous estimates. That's totally within the range of what modern spotted hyenas can bite. And that really got me thinking about just what kind of predatory role these juveniles had in their ancient environments. Perhaps they were more formidable predators than we previously realized and potential competitors with the larger terrains for individuals. People should care about fossils not because they're inherently interesting and fascinating because it represents a world that no longer exists today, but also they're becoming increasingly relevant. There has been a lot of different adaptations to life on earth, as we know it, but is there a limit to how big you can get, how small you can get, or how hard you can bite? And that really is what drives me. How weird can life get in the past and where are we gonna go in the future?