Sandra Rehan

Associate Professor of Biology

The Rehan lab research focus is bee biodiversity and social evolution. We have a special interest in the origin and maintenance of social behaviour in bees. The lab has three main foci: molecular phylogeny, behavioural ecology, and comparative genomics. We employ these three levels of biological integration to study bees at multiple evolutionary scales. Research in the lab ranges from natural history and taxonomy to molecular phylogenetics and biogeography. We study solitary and weakly social bees to understand the genetic underpinnings and ecological constraints selecting for social behaviour.  Work in the lab includes field observations to explore the life history and ecology of bees in their natural habitats and lab based experiments to investigate behavioural plasticity.  We use genomics to uncover the genetic basis of group formation and transcriptomics to understand the epigenetic modifications involved with social experience.

In studying bee biodiversity, we have a strong passion for documenting these charismatic species. Using macrophotography and microscope imaging, we are able to capture the distinct morphologies and showcase the beauty of wild bees. We also use these techniques to aid in training bee taxonomy, archiving specimens, and describing new species. The conservation of wild pollinators requires in-depth knowledge of their diversity, habitat requirements, and responses to environmental stress. We conduct long term studies of bee biodiversity across landscapes to determine plant-pollinator associations and the status of wild bee communities. Historical data and experimental manipulation of landscape settings allows us to determine the habitat requirements and status of wild bee species to make sustainable land use and conservation recommendations. Our biodiversity survey specimens offer invaluable data to discover cryptic species, study species ranges, adaptation and ecological niches using comparative morphology, population genetic, and geospatial modelling techniques.

Representative Publications

Dew RM, McFrederick QS, Rehan SM (2020) Diverse diets with consistent core microbiome in wild bee pollen provisions. Insects. 11:49

Lawson SP, Kennedy K, Rehan SM (2020) Pollen composition significantly impacts development and survival of the native small carpenter bee, Ceratina calcarata. Ecological Entomology. In press.

Mathiasson ME, Rehan SM (2020) Wild bee declines linked to plant-pollinator network changes and plant species introductions. Insect Conservation and Diversity. In press.

Nooten SS, Rehan SM (2020) Historical changes in bumble bee body size and range shift of declining species. Biodiversity and Conservation. 29:451–467

Odanaka KA, Rehan SM (2020) Wild bee distribution near forested landscapes is dependent on successional state. Forest Ecosystems. 7:26

Oppenheimer RL, Rehan SM (2020) Inclusive fitness of male and facultatively social female nesting behavior in the socially polymorphic bee, Ceratina australensis. Annals of the Entomological Society of America. In press. DOI:10.1093/aesa/saaa022

Steffen MA, Rehan SM (2020) Genetic signatures of dominance hierarchies reveal conserved cis-regulatory and brain gene expression underlying aggression in a facultatively social bee. Genes, Brain and Behavior. 19:e12597

Dew RM, Silva DP, Rehan SM (2019) Range expansion of an already widespread bee under climate change. Global Ecology and Conservation. e00584

Mathiasson ME, Rehan SM (2019) Status changes in the wild bees of northeastern North America over 125 years revealed though museum specimens. Insect Conservation and Diversity. 12:278-288

McFrederick QS, Rehan SM (2019) Wild bee pollen usage and microbial communities covary across landscapes. Microbial Ecology. 77:513-522

Nooten SS, Rehan SM (2019) Agricultural land use yields reduced foraging efficiency and unviable offspring in the wild bee Ceratina calcarata. Ecological Entomology. 44:534-542

Odanaka KA, Rehan SM (2019) Impact indicators: effects of land use management on functional trait and phylogenetic diversity of wild bees. Agriculture, Ecosystems and Environment. 286:106663

Shell WA, Rehan SM (2019) Invasive range expansion of the small carpenter bee, Ceratina dentipes (Hymenoptera: Apidae) into Hawaii with implications for native endangered species displacement. Biological Invasions. 21:1155-1166

Shell WA, Rehan SM (2019) Social modularity: conserved genes and regulatory elements underlie caste-antecedent behavioural states in an incipiently social bee. Proceedings of the Royal Society B. 286:20191815