Fire rituals and the collective entrainment of crowds

What is our study about?

Fire has been integral to human evolution for at least 1 million years, providing a source of heat for cooking, protection, and tool-making. Less appreciated is the importance of fire as a source of light, as a mediator and enhancer of social interactions. Growing attention has focused on firelight as an essential component of human rituals and experience: whether it is in the stories we share while sitting around campfires, or the ways we use fire festivals as touchstones of the cultural calendar. Firelight provides more than just illumination in the long dark hours––it flickers and pulses with its own rhythm, factors that affect our internal physiology. Intriguingly, the visual properties of firelight may facilitate social connections and shape our brain activity in ways that help us synchronise behaviour across individuals.

What ideas are we testing?

We (Dr Cat Hobaiter, University of St Andrews, and Prof. Nate Dominy, Dartmouth College) are testing the idea that firelight and its flicker-rate can promote behavioural synchrony within a large social group, a phenomenon termed collective entrainment. We will use video data to look at whether people in a crowd synchronise their speed, spacing, and footsteps when they are walking around a fire. In doing so we hope to provide a new perspective to the age-old question of why fire exerts such a powerful influence on the human social behaviour.

What data are we collecting?

We use data from a thermal drone flown at 150m above the crowd to look at the spacing between people. No one can be identified from this data. Each person appears as a very small bright dot on a dark background. We also use a fixed camera at foot-height to film footsteps. You can only be identified from these videos if you have individually identifiable shoes on, or if you choose to bend down and look directly into the camera. The data we collect from these videos are not connected with any individual or their identity and cannot be linked back to them. All videos are stored indefinitely on a password protected server by the researchers. Storage is subject to periodic review every 10-years.

How could this research benefit people?

Fire-mediated social synchrony and cohesion may alleviate individual feelings of isolation or marginalisation. We hope to understand whether, when practiced safely, social events around firelight might contribute positively to public health and wellbeing.

How to contact the researchers

If you have concerns or questions about our study, please email Dr Catherine Hobaiter on clh42 @