Interview Text1) In the paper "Tyrannosaur Paleobiology: New Research on Ancient Exemplar Organisms" you and your team are assessing the current state of research involving tyrannosaurs. How has it evolved and what were your most significant findings?
There is no doubt that Tyrannosaurus rex and its close relatives are the most familiar dinosaurs to the public, but they are also popular subjects of research. Our knowledge of these animals has literally exploded over the past decade. T. rex has been a dinosaur icon for a long time, but just 10 years ago the only tyrannosaurs we knew about were T. rex and a handful of close relatives from the Late Cretaceous. Today we recognize about 20 tyrannosaurs, and we probably know more about them than any other dinosaurs: how they fed, how they moved, how they grew, where they fit into the dinosaur family tree and what types of animals they evolved from. They truly are model organisms, so to speak, for vertebrate paleontologists, used to study many themes and to make explicit comparisons between the biology of dinosaurs and living organisms.
2) Did you find anything surprising?
The most novel part of our research is that we have compiled a new, comprehensive family tree of tyrannosaurs. Just like many of us are interested in our own family genealogies, we’re interested in the evolutionary relationships of tyrannosaurs. This research has highlighted three main themes that may seem surprising to many people. First, the tyrannosaurs were an ancient group: they originated at least 100 million years before T. rex lived. Second, the earliest tyrannosaurs were small animals, no larger than a small dog, and for the first 80 million years of their history tyrannosaurs were small animals. Third, T. rex and its close relatives are restricted to North America and Asia, but earlier in their history tyrannosaurs lived all over the world. So, really, this tells that this great icon of prehistory, T. rex, is merely the tip of the iceberg of the diversity of tyrannosaurs.
3) What are the main characteristics of tyrannosaurs?
All tyrannosaurs are predators, from the smallest and oldest species all the way up to T. rex. They all walked on two legs, all had robust "incisor-like" teeth at the front of their mouth, a fused snout that was optimized for strength, and an extensive system of sinuses in the skull filled with air sacs, probably for more efficient breathing.
4) How do you think these findings will change the way tyrannosaurs are viewed?
Having a comprehensive family tree is always important for context. Just as we can better understand our own family history if we know how our various relatives are related to each other, we can better understand the evolutionary history of tyrannosaurs with the aide of a family tree. All of the new discoveries—and our family tree is only possible because of the avalanche of new discoveries made by many of our colleagues over the past decade—tell us that tyrannosaurs were very different animals than their popular image conveys. They began as small animals, and for most of their history lived in the shadow of other giant predators, and only very late in the Age of Dinosaurs did they evolve gigantic size. T. rex was in many ways a very odd, unusual tyrannosaur. It was not the norm for this group that was mostly small and ecologically marginal for most of their 100 million years on the planet.
5) What is the next step for your research?
We will continue to work on tyrannosaurs, on many fronts. Personally, I am now working on more detailed descriptions of the anatomy of several species, and this will help further refine the family tree. My colleagues are actively looking at how tyrannosaurs behaved as living animals, from the smallest and oldest forms up to T. rex: how they fed, moved, reproduced, and grew. Many surprises are surely in store, and each new fossil discovery can drastically change our views.
6) How did you get interested in science? Do you have any advice to young people who might want to learn more about paleontology?
I became interested right around the time I was starting high school. My youngest brother was just going through the "dinosaur phase," and had a lot of books sitting around, and it stoked my interest. I grew up in northern Illinois, where there are no dinosaur fossils, but with a high school teacher I would visit local invertebrate fossil sites. I went onto study geology in college, and continue today as a PhD student. My advice to all young people interested in science is to never stop exploring, never stop being curious about the world around you, and to never be afraid to challenge yourself. Take all the science and math classes you can, but try to be a well rounded student. Scientists are often perceived as either abnormally smart or abnormally geeky people. Most scientists are neither geniuses or supernerds. The key to being a scientist is learning how to think critically and ask questions about the world around you, and really, most scientists are normal people that like watching football and going to the beach and listening to music.
These are Steve Brusatte's written remarks. Please refer to the video interview for exact quotes.