Periodic Reporting for period 4 - BeeDanceGap (Honeybee communication: animal social learning at the height of social complexity)
Okres sprawozdawczy: 2020-08-01 do 2021-01-31
To address the first of these questions, we assayed the changes in gene expression that occur within the bee mushroom bodies- an area of the brain that is associated with learning and memory- immediately after following a dance. We identified genes that respond to the acquisition of spatial information through the dance, and compared them to those that are involved in acquiring the same information through individual experience. We found that Apidaecin was consistently expressed in the same way through both mechanisms.Therefore there is suggestive evidence that points at a role for apidaecin in the regulation of cognitive functions in the honeybee mushroom bodies associated with foraging behaviour.
To address the second question, we assayed the importance of dance-following for food discovery under varying forage distributions. Foragers have multiple information sources available to them in the nest, and we developed and used network-based diffusion analysis models to evaluate the relative contribution of each pathway to real-world food discovery. We found that the waggle dance is critical to the discovery of new food sources when colonies shift focus from one patch to another of the same type, but may be far less critical when bees revisit food sources or shift between species. A better understanding of the extraordinary social communication system of these remarkable insects extends our knowledge of sophisticated collective behaviour, but it also provides insight into a critical information pathway that drives one of the world’s most important and threatened pollinators to food. Our research is important not simply because honeybee foraging behaviour is an evolutionary marvel, but because it is a significant contributor to pollination services at a global scale.
The second axis of the project focused upon the use of network-based diffusion analysis (NBDA) to compare the contribution of the different information pathways that are available to honeybees. The core assumption underlying NBDA is that if social transmission is occurring, then the spread of a novel behaviour should follow a social network that reflects opportunities for information transfer between individuals. However, earlier iterations of NBDA had several limitations. The approach that we developed, in order to achieve our primary aim of assaying information flow through bee colonies, built on this by incorporating multiple dynamic networks for comparison within a single model. We published this tool as an R-package and disseminated further through an accompanying extensive “How To” paper to encourage uptake by other ecologists, and through workshops at international conferences. We went on to apply our approach to our own empirical data, comparing the importance of three different honeybee communication systems as drivers of forage discovery. We showed that the waggle dance is critical to the discovery of new food sources when colonies shift focus from one patch to another of the same type, that it is not important for food rediscovery, that reliance on it does not vary with distance forage and that it may be less important for shifts between forage types. These results indicate that within-species forage shifts may have been key to the evolution of this unique communication system, and each has been presented at multiple conference symposia and is either published or in the process of publication.
We have introduced next-generation transcriptomic approaches to the study of animal social learning- a psychology-based subject area that rarely overlaps with molecular biology. Through this, we have shown that even very brief signal exposure (following dance circuits over the course of a single morning) has a molecular signal at the transcriptomic level.