Buzzing Bees
Bees have been around since just after the first flowering plants appeared. They are very important to the ecology of most habitats as they are the primary pollinators of plants that are pollinated by insects (entomophilous).

There are more than 20,000 known species of bees in the world, by far the greatest portion of these are solitary. By solitary we mean that a single female, after she emerges from her pupae and is mated by a male, constructs, provisions and lays an egg cell in a nest by herself. The social (called eusocial) bees like the Bumble Bees, Honey Bees, Sweat Bees, and Stingless Bees, all of whom have a Queen who lays eggs and a number of workers who look after them.

Many solitary bees nest near where they emerged, especially soil, wood and wall nesting species. There may sometimes be hundreds of thousands nesting in one area. Most nest in the ground, in well drained soils of varying degrees of slope. Many ground nesting species pile the soil form the burrow up in a volcano hillock around the nest. The depth of the burrow depends on the species and soil type, those that nest in very dry oil lend to dig deeper holes.