From Fossils to Story: How We Know Dinosaurs with Riley Black

Paleontologist Riley Black explains how scientists piece together dinosaur life from partial bones, traces, and skin clues. The episode dives into how skeletons form hypotheses, how trace fossils reveal behavior, and how color evidence is changing our picture of the Mesozoic world.

• Skeletons are incomplete and are interpreted using relatives and physics
• Trace fossils such as tracks, bite marks, and coprolites illuminate movement and diet
• Ornamentation like sails and horns raises questions about function and signaling
• Amateur and professional paleontologists alike contribute to the discoveries

Overview

The podcast features Riley Black, a professional science writer and amateur paleontologist, discussing how paleontologists turn fossil bones into stories about dinosaurs. With a mix of bones, models, and trace evidence, Black explains the iterative nature of scientific reconstruction, where each new find can revise long-held ideas.

From Skeletons to Hypotheses

Early fossil discoveries often yielded disarticulated, incomplete skeletons. Black explains how early reconstructions treated dinosaurs as giant reptiles, and how later, more complete skeletons and comparisons with close relatives like Giraffatitan reshaped our understanding of body plan and posture. She uses the Tyrannosaurus rex hand as a prime example of how a tiny bone can reveal a lost feature (the ancestral third finger) and force a revision of the animal’s limb anatomy. Even today, many dinosaur reconstructions are best described as hypotheses supported by the available evidence rather than definitive blueprints.

Counterintuitive Clues: Ornamentation and Sails

Dinosaurs flaunted bizarre structures—horns, spikes, sails, and other adornments. Ouranosaurus with a sail on its back is highlighted as an example of how such features may have served signaling roles or other functions. The discussion also touches on Spinosaurus, skewing common images of dinosaur appearance. Black emphasizes that the presence of ornate structures invites multiple plausible explanations, and color or skin evidence could help distinguish among them.

Trace Fossils: The Evidence of Behavior

Trace fossils—including footprints, tooth marks, nests, and coprolites—provide temporal windows into behavior that bones alone cannot. Tracks allow estimates of speed and gait, and bite marks on bones can reveal predator-prey interactions. Coprolites (fossilized dung) offer direct glimpses into diet, helping to answer whether a dinosaur was insectivorous, herbivorous, or omnivorous. Black stresses that traces are a crucial complement to bones in reconstructing life histories.

Fieldwork and Case Studies

Black recalls fieldwork in Utah where an aetosaur track plus beetle traces in Triassic rock helped identify an animal lineage and its behavior. She explains how scientists match footprints to skeletal anatomy and how a few well-preserved traces can upend assumptions based solely on bones. The discussion also covers how insect traces on bones and the presence of dermestid beetle damage inform burial and fossilization timelines, reshaping our understanding of fossil formation.

The Color of Dinosaurs and the Public.

In recent years, researchers have used skin impressions and comparisons with modern birds to infer color and pattern in dinosaurs, revealing color as a real and informative trait rather than mere speculation. Black notes how these color reconstructions add depth to our understanding of behavior, mating, and concealment. She emphasizes paleontology as an accessible field where volunteers and museum staff can contribute to the science through tasks like sorting drawers, cataloging fossils, and assisting with fieldwork.

Reflections and Implications

The host and Black discuss the evolving nature of paleontology as a field that welcomes broad participation. The Last Days of the Dinosaurs is recommended as a starting point for readers interested in a narrative approach to prehistory. The episode ends with an invitation to engage with the science and participate in the ongoing discovery of the ancient world.