Current Research Trends in Honey Bee Nutrition

Honey bees play a vital role as a major pollinator in both natural and agricultural ecosystems. In recent years, we have witnessed an alarming decline in honey bee populations worldwide, which poses a threat to global food security. The health and welfare of honey bees are heavily dependent upon the supply of an adequate amount and balance of macro- and micronutrients at both individual and colony level. Failing to achieve this nutrient target engenders nutritional stresses, which are thought to be one of the main factors driving the decline in honey bees and other pollinators. Besides their direct effects, nutritional stresses can seriously compromise health and fitness in honey bees through interacting with other types of biotic and abiotic stresses, such as pathogens or parasites, pesticides, climate extremes, etc. To cope with this ongoing honey bee crisis, there have been growing efforts to advance our basic knowledge of nutritional physiology and ecology of honey bees. Despite such increasing interests, our complete understanding of nutrition in honey bees has been hampered by the lack of an appropriate method that can deal with the multidimensional, interactive, and dynamic nature of nutrition. The Nutritional Geometry (NG) is a powerful, state-space modelling framework that is developed to visually analyze highly complex nutritional dataset in n-dimensional Euclidean space. The major objective of this review is to provide a comprehensive overview of the recent developments in honey bee nutritional research, which have been mainly achieved through the application of this novel framework. We first start this review by highlighting the importance of nutrition in the health and fitness in honey bees, especially in the context of their recent global crisis. Before introducing the key concepts and principles of NG, we outline the current status and limitations of conventional honey bee nutritional research and explain how NG has paved a new path towards understanding their nutritional biology from a multidimensional perspective. In the main body of this review, we summarize the key discoveries and implications drawn from recent studies that have explored the impacts of macronutrient balance on health in honey bees. Finally, we discuss how NG can further deepen our understanding of colony-level nutritional homeostasis in honey bees and also how this approach will help us to develop nutritional interventions that can mitigate and, hopefully, stop the honey bee population decline.