Bird Skulls May Reveal the Inner Lives of Dinosaurs Like T. Rex
Scientists believe that the skulls of birds may hold the key to understanding the inner lives of long-extinct dinosaurs, including the mighty Tyrannosaurus rex. Professor Steve Brusatte, a palaeontologist at the University of Edinburgh, who famously states that 'birds are dinosaurs,' is at the forefront of this research.
Brusatte explains that while T. rex is often depicted as more brawn than brains, researchers are now hoping to probe what was going on inside its head by studying its living relatives: birds. Previous studies have shown that some bird species not only make and use tools but can also plan ahead and display basic forms of empathy. For instance, laboratory tests suggest that emus can recognize that other birds may have different experiences from themselves.
Now, scientists are exploring whether there are telltale hints of these cognitive abilities in the skull structure. This could open up the potential to investigate the lived experiences of dinosaurs like T. rex. 'We can't put T. rex through those tests,' Brusatte said. 'But if there are some distinctive features of the brain that maybe tell you with 95% confidence that the animal with that kind of brain is capable of that kind of behaviour today, then we can at least make predictions about these fossils.'
In his new book, The Story of Birds, Brusatte describes working with an international team to explore these possibilities. The approach might be a long shot, but it builds on the fact that birds are direct descendants of dinosaurs. While many dinosaurs were wiped out 66 million years ago when a colossal asteroid struck Earth, one group survived: birds.
'I don't think it's totally percolated into the popular consciousness that birds are dinosaurs,' Brusatte said. 'They are real, true dinosaurs. This is not a turn of phrase.'
The book traces the incredible journey of avian-kind, revealing how small cousins of Velociraptors eventually gave rise to the diverse birdlife we see today. 'It's not like a T. rex mutated into a chicken one day, and that's how you got a bird from a dinosaur,' Brusatte explained. 'It was a long, gradual process of evolution through natural selection.'
Features like feathers and wings initially had nothing to do with flight. 'It just so happened that you had feathers that had probably originally evolved for insulation to keep these dinosaurs warm. They've been modified into these display structures, these advertising billboards sticking off of the arms of some of these dinosaurs,' he said. Over time, some dinosaurs became small enough and had wings big enough to gain lift and thrust.
Early birds had teeth, claws, or long tails, and there were likely many different approaches to getting airborne. 'There was a whole fantastic aviary of birds flapping and fluttering overhead of T. rex and Triceratops until the asteroid hit,' Brusatte said. 'All of those birds then died. Except for the modern-style birds.'
These survivors of the fifth mass extinction had several advantages: they were strong flyers, grew rapidly from chick to adult, lived on the ground, and waded in shallow water. Their toothless beaks allowed them to eat seeds, which remained in the soil even after forests collapsed in the 'impact winter.'
After the extinction, evolution gave rise to fearsome creatures like the terror birds, which stalked South America for tens of millions of years. Reaching up to 10 feet in height, with a head larger than a horse's skull and razor-sharp hooked beaks, these birds were top predators. 'This was basically T. rex reincarnated,' Brusatte said.
The connection between birds and dinosaurs is not just evident in fossils but also in DNA. A six-day-old quail embryo has a pelvis that looks just like the hips of a theropod like T. rex. Furthermore, by tinkering with the genes of a chicken embryo, scientists can trigger the development of teeth, albeit fatally for the chick. 'When I look at these things and I see the photos of these genetic experiments, and I read the research papers, my mind is blown,' Brusatte said.
The Story of Birds features charismatic creatures from the 150-million-year-old Archaeopteryx, the oldest fossil bird, to the enormous 'Demon Ducks,' flightless birds like the Dodo, and the hoatzin, a punky leaf-eating bird that constantly belches. Brusatte also voices concern over threats facing birds today, such as avian flu, habitat loss, poisons, killer cats, and glass buildings. However, he remains upbeat: 'Birds are survivors. They are adaptable, they evolve quickly, they change quickly. When they are confronted with a crisis, maybe not all of them make it through, but some of them do, and they can repopulate really quickly. That is the story of the asteroid. They were the only dinosaurs to survive.'
