Chandra lab

Brain Origins Laboratory

We study how animals first evolved brains, and how these early brains enabled new computational abilities and the origins of complex behaviour.

The evolution of brains from ancient diffuse nerve nets was a landmark in animal history, enabling early predatory lifestyles and the building blocks of cognition – from feedback control to flexible learning and internal representations. How were the first brains organised? Acoel worms, thought to be the sister lineage to other brainy animals, offer a unique window into early brains. We have developed a lab-tractable acoel, the three-banded panther worm Hofstenia miamia, as a new neuroscience model.

A marine predator with a rich behavioural repertoire, Hofstenia has an unusual 'diffuse brain'. It displays a remarkable robustness to injury: it can hunt its prey even while missing the majority of its brain. And it lacks the specialised regions of conventional brains, instead appearing to be built from tiles of circuits that each perform most or all computations. This decentralised architecture might resemble the organisation of the earliest animal brains. Understanding Hofstenia's unfamiliar brain can teach us about how our own brains first came to be, and how nature builds robust computing systems.

Using methods from systems neuroscience, genomics, molecular biology, computational ethology, and physics, we seek to understand how Hofstenia's diffuse brain is organised, how it computes, and how it generates coherent behaviour. By comparing Hofstenia to other acoels and to animals across the phylogeny, and through experiments on artificial neural networks, we ask how brains and behaviour evolve over deep time.