Collage of many different human faces. Courtesy of Shutterstock

The 2015 invited speaker was Professor David Perrett FBA FRSE, Wardlaw Professor at the University of St Andrews. 

In his talk ‘What’s in a face? The biology of attractiveness’, Professor Perrett discussed the ways in which humans determine someone else’s health, fitness and resilience to illness based on facial judgements – the biological basis of attractiveness.

We all make judgements based on peoples’ faces every day of our lives – our choice of partner, who we trust etc – which is important in both our personal and professional lives – but we are largely unaware of the accuracy of or the basis of these opinions. Skin tone, 3D face shape and expressive cues aid us in forming these judgements. Impressions of intelligence, for example, can be enhanced by eyelid-openness and subtle smiling.

We judge health based on both facial shape and colour information – not just the colours imparted by blood flow and sun-tan but also the ‘golden glow’ imparted in skin by carotenoid pigments from fruit and vegetables in our diet (for example, carrots, cherries and tomatoes) – this colour is viewed as attractive and healthy across many cultures and ages groups – and indeed amongst other species. In humans, carotenoid colour is raised by many aspects of a healthy lifestyle and may thus provide an index of wellbeing in terms of fitness, resilience to illness, etc.

3D surface information provides face shape cues to body height and weight but also to health in terms of heart and circulatory health and predisposition to illness. Men and women have differently shaped faces – enhancing or diminishing these sexual differences alters attractiveness but the exact impact on attractiveness varies with many biological and cultural factors. Wealth and poverty, the desire for offspring and one’s own attractiveness alter how attractive we find different facial attributes.