Förderer: DFG, Project number 467682864
The Western honeybee (Apis mellifera) has long been a pivotal model organism in neuroethology, whereas the ecology of honeybees has attracted less attention. The elaborate division of labour and the highly efficient dance language of honeybees are ideal behavioural syndromes for studying adaptation of social behaviour to food resource availability. The genus Apis comprises three major groups: cavity-nesting honeybees, dwarf honeybees and giant honeybees. Whereas the behaviour and ecology of the Western honeybee has been studied in some detail, next to nothing is known about the foraging ecology and division of labour for other Apis species, which only occur in Asia. Southern India provides unique conditions for studying both Asian and Western honeybees in the same habitats. Together with our Indian partner, Prof. Hema Somanathan (IISER Trivandrum, India), we aim to conduct an in-depth comparative study on the foraging ecology and social organisation of representatives of all three Apis groups in natural and human-modified landscapes in Southern India. We will focus on the giant honeybee (Apis dorsata), the dwarf honeybee (Apis florea) and the cavity-dwelling Asian honeybee (Apis cerana) as well as the introduced Western honeybee (Apis mellifera). We aim to understand how changes in landscape structure affect foraging distances, dance dialects, and the spatial distribution, composition and quality of exploited floral resources of the four species. Our results are an important prerequisite for constructing plant-pollinator networks along land use gradients in India. We further aim to unravel the organisation of foraging labour in the four Apis species in different landscapes and want to identify the underlying mechanisms of behavioural organisation on different levels of the system. In a neuroecological approach, we want to understand the effects of different landscapes on neurotransmitter signalling in the brain and foraging-related decision making in the different honeybee species. The suggested project will thus gain important novel insights into the foraging ecology and social organisation of the three closely related Asian honeybee species and the introduced Western honeybee in a region, which is assumed to be the centre of honeybee evolution. Our results will further reveal important new insight into relationships between landscape composition, brain signalling and decision-making. We will provide valuable knowledge on the resource use of honeybees in different landscapes of India and thereby contribute to their protection under future conditions of global change.