Figure 1 . (a) Distribution of studies included in the meta-analyses (N=133). Circle sizes are proportional to the number of studies. (b) Green space in cities, such as parks and road verges can support diverse pollinators. (c) Photos of representative pollinator taxa included in our database, left to right: mammals (e.g., nectar-feeding bat), Aves (Calypte anna ), Lepidoptera (Chaospes hemixantha ), Hymenoptera (Halictus varentzowi ), Diptera (Allobaccha apicalis ), and Coleoptera (Brentidae sp.). The first two photos were adapted from Flickr under Creative Commons license CC BY 2.0., taken by Doug Greenberg and Becky Matsubara, respectively. The other four photos were by Dr. Xiao-Fang Jin.