Outcomes, limitations, and frontiers in bee functional ecology
Functional traits are increasingly providing a popular framework for making generalizable predictions about the impacts of global change on bee biodiversity. The majority of studies analyzed here reported significant effects of environmental variables on functional trait diversity or composition. These findings have helped to clarify patterns of community change in response to environmental disturbances. For example, one generally consistent finding in functional trait studies of urbanization is the tendency for urban environments to favor generalist, cavity-nesting species (Ayers and Rehan, 2021; Banaszak-Cibicka and Żmihorski, 2012; Buchholz and Egerer, 2020; Cane et al., 2006; Normandin et al., 2017). In other contexts, however, trait-mediated responses to environmental change variables may be weak or conflicting across systems (Bartomeus et al., 2018; Williams et al., 2010). The extent to which functional trait effects are generalizable across systems appears to be context- and trait-dependent.