Centris pallida is a species of solitary bee native to North America. It lacks an accepted common name; however, it has been called the digger bee, the desert bee, and the pallid bee due to its actions, habitat, and color respectively. The solitary nature of this bee allows for a dual-strategy mating system which produces an evolutionarily stable state resistant to invading strategies. These bees have also evolved to withstand the high temperatures of their native habitat. C. pallida routinely has internal temperatures within 3 degrees Celsius of death.
Centris pallida are located in dry, hot environments of North America. Specifically, they are in Arizona, Nevada, southern California, New Mexico, and western Mexico.[4] They are a very common bee (especially in Arizona), and are thus classified as Least Concern in terms of conservation.[5] The fur and dark colored exoskeleton allow the bees to survive the cold nights in the desert. During the daytime, C. pallida are almost completely inactive, hiding in shade or in burrows to prevent overheating.[6]
est autocorrélée. Ainsi, un marché a des chances de baisser au cours d'une année N s'il baissait déjà au cours de l'année N-1. Réciproquement, si les prix augmentent au cours d'une année, il existe de fortes chances pour qu'ils augmentent à nouveau l'année suivante. Des périodes pluriannuelles de hausse succèdent donc, après des retournements du marché, à des périodes pluriannuelles de baisse des prix ;
Male C. pallida are able detect the pheromones which females release and use them to locate female burrows. When a virgin female is about to emerge from her burrow, she releases a scent that wafts up through the soil and is detected by the antenna of the males. This has led to males developing a very acute olfactory sense. Freshly-killed females have been buried to test whether sound also plays a part in male signaling. In these tests, male bees still dug up the dead females, proving that pheromone signaling is the only pathway. Males have also been observed to dig up other males. This shows that males and virgin females give off similar pheromones. Oddly, males also sometimes dig up other digger bee species. It is currently unknown why this occurs.[6]