Pasha van Bijlert

Pasha van Bijlert mounting a Tyrannosaurus rex skull

I'm a biomechanist and a palaeontologist - I use 3D physics simulations to understand how animals move, and then place this knowledge within an evolutionary context. I believe locomotion holds the key to unravelling many unknowns in the biology and evolutionary success of dinosaurs. So far, my research has focused on Tyrannosaurus rex, but I am now expanding to more taxa, both alive and extinct.


3D fossil reconstructions, evolutionary biomechanics, locomotion, dinosaurs, optimal control



Simulating animal movement using 3D physics, to resurrect extinct dinosaurs

In nature, the capacity to move is vital to a (vertebrate) animal's survival, but there are many aspects of movement that we still do not understand. For instance: you cannot measure muscle forces, without operating on an animal (at which point movements will no longer be natural). Instead, I use musculoskeletal models: 3D scans of a skeleton are outfitted with digital muscles, and subjected to simulated physics - shining light on what happens inside the body while it is moving. This method allows you to resurrect an extinct dinosaur, but also to explain the movements of animals still alive today.

Musculoskeletal model of T. rex Trix
3D reconstruction of Triceratops

TedX talk on Tyrannosaurus rex walking speed

External video URL


  • van Bijlert P.A., van Soest A.J.K., Schulp A.S. 2021. Natural Frequency Method: Natural Frequency Method: estimating the preferred walking speed of Tyrannosaurus rex based on tail natural frequency. Royal Society Open Science 8:201441.

In the

I was featured in the BBC documentary Secrets of the Jurassic Dinosaurs, for which I developed a biomechanical model of Allosaurus (pictured below). I discuss dinosaur locomotion in the documentary.

    Simulation model of Allosaurus I made for the BBC
    BBC interview