Patterns of Evolution of Warm-Up Rates and Body Temperatures in Flight in Solitary Bees of the Genus Anthophora

Energetic considerations of preflight warm-up in bees predict that bees should warm-up as fast as they can and that larger species should be able to warm-up more rapidly. Larger species should also be able to maintain higher thoracic temperatures during light. These predictions are examined for 19 species in the solitary bee genus Anthopora (Hymenoptera; Apoidea; Anthophoridae). 2. The genus Anthophora has uniformly high warm-up rates and body temperatures in light, and the highest warm-up rates measured in any heterotherm. 3. Under standard conditions, both warm-up rates and thoracic temperatures during light increase with body mass in Anthophora, in keeping with the prediction that heterotherms should minimize the energetic cost of warm-up