Four varieties of bacteria have been found in the bee bread of the larva: Bacillus circulans, B. coagulans, B. firmus, and B. megaterium. Only the Bacillus genus has been found in the samples taken. Together, these four species were able to hydrolyze starch, ferment glucose, convert nitrates to nitrites, and produce dihydroxyacetone from glycerol. This group of bacteria also lowers the pH of the bee bread. These functions serve not only to protect the larva from other bacteria, but they also digest complex molecules which allow the larva to easily absorb nutrients without expending a lot of energy. The bacteria, in turn, receive a supply of food which results in a mutualistic relationship.
Centris pallida serve numerous roles for the environment. Like most other bees, they are essential for pollination. Specifically, they pollinate cacti, desert willow, and palo verde. The tunneling ability of these bees aerates the soil, and this allows water from rain to reach plant roots quickly. Their nitrogen rich feces fertilizes the soil. Their stings are mild, so they are not dangerous. The only downside with respect to humans is that their burrowing can leave unsightly mounds. If an area has a large density of burrowing females, then these mounds can be quite noticeable and are difficult to get rid of.
Centris pallida typically feed on flowers that can withstand the hot temperatures of its habitat. These plants include palo verde (Cercidium microphyllum and Cercidium floridium), ironwood (Olnyea tesota), and creosote bush (Larrea divaricata). The palo verde pollen is the most common, and it gives the bee bread a strong orange color. Due to the large expenditure of energy by males during hovering and/or patrolling, they must consume about 3.5 times their body weight in nectar each day.
Granby a la fibre artistique développée et tout fervent de culture s’y sentira bien. La municipalité a même érigé un musée à ciel ouvert ARTRIA dans plusieurs endroits stratégiques en harmonie avec le paysage. Une façon originale de redécouvrir sa ville chaque jour! Granby est aussi réputée pour son Festival international de la chanson et sa vie culturelle bouillonnante.
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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.