The aim of our research is to understand the diversity of colour in plants and animals. We study the proximate (pigments, structure) and ultimate (fitness, visual function, temperature) underlying this diversity. We particularly focus on the colours of flowers and insects: how do they create their colours, and how are these colours perceived in the eyes of their natural observers (pollinators, mates, antagonists)? 

Our Human Frontiers in Science Program project focuses on how shiny visual effects determine visibility to insects. In nature, most colours are matte, yet across the tree of life, many species have evolved optical structures that create a bright flash when observed under a specific angle. How does shininess contribute to visibility? In our group we study the optical and anatomical properties of glossy flowers and flashy butterfly wings. Together with Darrell Kemp (Macquarie University, Sydney) we study how flashiness of butterfly wings determines visibility to potential partners. Our collaborator Michiyo Kinoshita (Sokendai Hayama, Japan) studies how butterfly visual systems and brains process flashy visual effects. 

In other projects we study how flower colour and rewards evolve upon a switch between pollinators with different visual systems and/or dietary preferences. How flower colour is linked to the nutritional quality of floral rewards is studied together with the group of Sara Leonhardt (Freising, Germany). With Barbara Gravendeel (Naturalis, Leiden) we study how sexually deceptive orchids resemble the colours of the female insects that they mimic. Through behavioural experiments in the group of Johannes Spaethe (Würzburg, Germany) we study how bumblebees respond to different types of visual effects. Together with Kira Tiedge (Groningen) we investigate the impact of abiotic stress on flower development, and how that cascades to pollinator resources.