Applications are invited for a self-funded PhD project to investigate cognitive skills in solitary and social bees. The supervisors will be Dr Gema Martin-Ordas and Dr Mario Vallejo-Marin (University of Stirling). The adapted intelligence hypothesis (Toby and Cosmides, 1992) proposes that cognitive abilities evolve in response to environmental challenges. For this reason, it is argued that some birds might have remarkable memory abilities or honey bees complex systems of communication (Shettleworth, 1998). In this regard, some authors have proposed that cognition might have evolved in response to foraging demands [the ecological intelligence hypothesis (e.g., Milton, 1988)], whereas others have proposed that cognition evolved in response to the demands of a complex social life [the social intelligence hypothesis (e.g., Byrne & Whiten, 1988)]. On this point, solitary and social bees provide us with a natural experiment in which to test these different hypotheses in invertebrates. Previous research with social bees has shown that bees can quickly learn to exploit new floral resources, and that they are capable of even learning to solve problems never before encountered in their evolutionary history to access food rewards (e.g., pulling strings or “playing football”). In contrast, research on solitary bees has received less attention. This PhD project will investigate different cognitive abilities associated with social and physical cognition in both solitary and social bees. The results of this research will shed light on the minimum mechanisms for cognition to evolve and on whether the evolution of cognition is driven by the same factors as in vertebrates. Thus, the findings will provide crucial insights for theories of evolution.