in their cells for nearly a year before emerging as adults.
Some bees, however, like certain leafcutters, yellow-faced bees, many sweat bees and small carpenter bees, produce several generations a year. Social species like bumblebees and some sweat bees produce multiple broods of workers. Male bees have no role in building nests, collecting pollen or caring for offspring. Their primary role is mating.
Ants and termites live cooperatively and are considered social, unlike butterflies which are solitary. Bees display a variety of social living arrangements, and some of them are solitary. Amazingly, certain sweat bees have built-in flexibility to live a solitary or social existence. Most bees, however, are one or the other.
Solitary species live alone and are self-dependent. A single female mates, builds her own nest, collects her own pollen, provisions her own cells and lays her own eggs; all without the assistance of another female. She does not interact with her offspring and usually dies before they become adults. Solitary bees often nest in dense aggregations, with many individual nests closely packed together. This gives the appearance of an organized colony, but aggregations are only a collection of individual nests. Most Missouri bees are solitary.
Females of social species work collectively to provision and sometimes defend a nest, and to produce offspring. A group can be as few as two or three (for some sweat bees species) to as many as several hundred (bumblebees). With some non-native social species, such as the honeybee, nests can include tens of thousands of individuals.
Bumblebees are the most well known group of native social bees. After mating in the summer or fall and then overwintering, a single fertilized queen begins building her nest in the spring, just as a solitary species would. She collects pollen, lays a small clutch of eggs and feeds her offspring, which soon turn into adult females. However, instead of leaving to start their own nests, these females stay with the queen and become the first of her worker force. They help her and the colony by collecting pollen, defending and maintaining the nest, feeding the offspring and caring for the queen.
The queen stays in the nest and is the sole or primary egg-layer. At some point in the summer, the queen begins laying some eggs that become males, as well as some that become next year's queens. These individuals mate, and the potential queens enter dormancy underground or elsewhere. By