Floral evolution in Solanum
The genus Solanum (Solanaceae) includes approximately 1500 species with a variety of habits from annual herbs to vines to small trees. Yet, most species of Solanum have similar and easily recognized flowers with 5-part corollas and anthers arranged in a cone in the centre of the flower. Exceptionally, these typified flowers evolve to produce two or more sets of anthers that can vary in shape, size and colour. Heteranthery, as this type of anther polymorphism is known puzzled Darwin for many years, and has been demonstrated to represent the functional division of labour within flowers into fertilising and feeding functions. You can find out more in this review paper.
In collaboration with our colleagues at Stirling, we have recently described handedness and interspecific learning in bumblebees stealing nectar from flowers of yellow rattle (Rhinanthus minor) in Switzerland. This work is covered in a popular-science article in The Economist.