The Food and Agriculture Organization of the United Nations (FAO) estimates that of the 100 crop species that provide 90% of food worldwide, 71 are pollinated by bees.
In an average bee colony, there are –
a) one fertile queen, whose main activity is egg- laying,
b) from 20 000 to 80 000 sterile female worker bees, which do almost everything that needs to be done in the colony, and
c) from 300 to 800 fertile males, generally called drones.
In addition, there are about 5 000 eggs and 25-30 000 immature bees in various stages of their development, called the brood. Of these, some 10 000, newly hatched, are the larvae, which have to be fed by the workers, while the remainder, after the larval stage, are pupae, sealed into their cells by the workers to mature. They are called the sealed brood.