Ancient Bird Brains and Beaks: New Fossil Discoveries Reshape Dinosaur Science

Recent scientific studies are providing new information about the capabilities and physical adaptations of ancient dinosaur species, including birds, by examining modern bird behavior and fossilized remains.

Brain Structure and Behavior in Dinosaur Fossils

Researchers are investigating whether features of modern bird brains associated with complex behaviors can be identified in dinosaur skulls. Some bird species are known to make and use tools, plan ahead, and show basic forms of empathy. Laboratory tests have suggested that emus can recognize that other birds may have different experiences.

Scientists aim to determine if brain features indicative of these behaviors in modern birds can be identified in dinosaur fossils.

"We can't put T rex through those tests. 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."
— Prof Steve Brusatte, paleontologist at the University of Edinburgh

Birds are considered dinosaurs, having evolved from small theropod dinosaurs. Features like feathers and wings initially evolved for insulation and display, not flight. Early birds existed alongside Tyrannosaurus rex and Triceratops until the asteroid impact 66 million years ago. Modern-style birds survived due to traits such as strong flight, rapid growth, ground-dwelling, wading ability, and toothless beaks that enabled seed consumption.

Specialized Mouth Features in Archaeopteryx

A separate study published in The Innovation has revealed that Archaeopteryx, the oldest known bird, possessed specialized mouth features similar to those found in living birds. These features include extra tongue bones, a sensitive beak-tip, and fleshy structures (oral papillae) on the roof of its mouth. The findings date back to the Jurassic Period, approximately 150 million years ago.

Archaeopteryx is recognized as the earliest known dinosaur to also be classified as a bird. Distinguishing early birds from other small, feathered dinosaurs has historically been challenging for paleontologists.

"These newly identified mouth features provide new criteria for differentiating bird fossils from other dinosaur fossils."
— Jingmai O'Connor, lead author and associate curator at the Field Museum

The research is based on the "Chicago Archaeopteryx," a fossil acquired by the Field Museum in 2022 and scientifically described in 2025. Fossil preparators, led by Akiko Shinya, spent over a year preparing the specimen, using ultraviolet (UV) light to identify and preserve soft tissues and small bone fragments.

Identified Mouth Structures

During preparation, microscopic features were observed in the skull, including:

• Oral Papillae: Fleshy, cone-like structures on the roof of the mouth, similar to those in modern birds that help guide food and prevent it from entering the windpipe. This marks the first discovery of oral papillae in the fossil record.

• Tongue Bone: A small bone indicating Archaeopteryx had a highly mobile tongue, akin to many contemporary birds. These bones provide muscle attachment points, enabling flexible tongue use for manipulating food.

• Bill-tip Organ: CT scans revealed nerve traces at the tip of the beak, suggesting a sensitive bill-tip organ. Many modern birds use such an organ to locate food.

Implications for Flight and Feeding

The presence of oral papillae, tongue bones, and bill-tip organs in Archaeopteryx indicates that early birds developed multiple strategies for efficient food finding and swallowing. Researchers suggest these adaptations are directly related to the significant energetic requirements of flight.

"These discoveries show a clear shift in dinosaur feeding mechanisms as they began flying and needed to meet substantial caloric demands."
— Jingmai O'Connor

Birds possess highly efficient digestive systems, with modifications throughout to maximize eating efficiency and nutrient extraction, starting with the mouth.