Dance is a universal human and animal behaviour. There are many species that use dance as part of their courtship displays, but could the ability to dance “well” also make you a winner in other evolutionary stakes?
A recent study from the University of Northumbria (UK) used male and female ratings of dance quality and quantitative measurements of the movement patterns to assess the best ‘killer moves’ for female dancers (McCarty et al, 2017). Three types of movements contributed: hip swings, asymmetric movements of the thighs, and asymmetric movements of the arms. The authors conclude that while hip swings may be a trait associated with courtship in Western societies, that the ability to move limbs asymmetrically points to better-developed motor control and rhythm keeping as it is a more complex pattern of synchronicity with the beat than more symmetric movements.
What causes some people to be able to better move in time to music? A network of nerve cells deep in the brain act in concert to isolate the rhythm or beat from external auditory signals, allowing us to predict the timing of subsequent beats and fire our muscles to move accordingly. Scientists call this “entrainment” and according to Aniruddh D. Patel, a neuroscientist at Tufts University, we can stay synchronised to a beat whether it slows down or speeds up by 30% (Singer, 2017). The better we are at predicting subsequent beats, the better we are perceived to be as dancers. This is a process which is increasingly also being identified in animals as well as humans (remember that video of parrots dancing to different types of dance beats? https://www.youtube.com/watch?v=ZfsZG90P3eM). However, it seems that only humans so far do this type of synchronised dancing together in groups (called “social entrainment”).
But why would this be important from an evolutionary sense? … because people who dance together well do a whole heap of other things together well too. Group cohesion, or the feeling of being part of something larger than oneself that creates the environment necessary for groups to work together better (to gather food or avoid predators or even take on other groups). Greater social cohesion also has physiological benefits. It can increase pain thresholds and elevate mood (via the release of endorphins, natural opioids in the brain).
There is indirect evidence that large group dances have taken place for thousands of years. “Aggregation sites” or large, heavily trampled areas where prehistoric musical instruments were also unearthed have been found in the French Pyrenees and other places (Singer, 2017).
That’s a lot of time to perfect our killer moves… so, what’s yours?
McCarty, K., Darwin, H., Cornelissen, P. L., Saxton, T. K., Tovée M. J., Caplan, N., and Neave, N. (2017). Optimal asymmetry and other motion parameters that characterise high-quality female dance. Scientific Reports 7, Article number: 42435 (2017). doi:10.1038/srep42435
Singer, T. (2017). The Evolution of Dance. Scientific American (July 2017), 317, 66-71. doi:10.1038/scientificamerican0717-66