213 — Breathing Life Into Dinosaurs: Tackling Challenges of Soft‐Tissue Restoration and Nasal Airflow in Extinct Species

In recent years, it feels as though it has become more common for paleontologists to encounter soft-tissue preservation in fossils. But it’s still very, very uncommon. How can we understand fundamental biology with no soft tissue?

It is common for paleontologists to look to bony-headed species for the best soft-tissue preservation, since the boniness contributes to higher-quality fossil preservation.

In this paper, researchers leverased the Pachycephalosauridae clade, which includes the eponymous Pachycephalosaurus as well as Stegoceras validum, a small (around seven feet tip to tail, and standing about as tall as a human butt) dome-headed dinosaur with rigid upper vertebrae (presumably to mitigate damage when using its dome head for whatever it is dome-headed dinosaurs did with their domes).

Bourke et al focus on the nasal passages of S. validum and use some very interesting technology to learn more about the soft-tissue biology of the Pachycephalosaurs. First, they used well-preserved samples to reconstruct 3D representations of a stereotypical skull. Then they used living examples of similar taxa to establish the most basic, conservative nasal passage model that was still feasible for this animal, using airflow simulations to constrain the generative parameters.

This led to a series of viable tissue configurations which the researchers were able to evaluate based upon their similarity to extant diapsids. From this, the researchers established that it was very likely that this Cretaceous dinosaurs likely had turbinate branched nasal conchae — spiral-form tissue that is most often found in endothermic organisms.

This suggests — much like more recent work — that dinosaurs were more warm-blooded-like than we thought: Perhaps they maintained a homeostatic brain temperature and allowed the rest of the body’s temperature to vary more?