THE BEES



Bee, common name for a winged, flower-feeding insect with branched body hairs.


Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila. There are nearly 20,000 known species of bees in seven to nine recognized families, though many are undescribed and the actual number is probably higher. They are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants.





A picture of a BeeCharacteristics Bees are dependent on pollen as a protein source and on flower nectar or oils as an energy source. Adult females collect pollen primarily to feed their larvae. The pollen they inevitably lose in going from flower to flower is important to plants because some pollen lands on the pistils (reproductive structures) of other flowers of the same species, resulting in cross-pollination. Bees are, in fact, the most important pollinating insects, and their interdependence with plants makes them an excellent example of the type of symbiosis known as mutualism, an association between unlike organisms that is beneficial to both parties.
Most bees have specialized branched or feathery body hairs that help in the collection of pollen. Female bees, like many other hymenopterans, have a defensive sting. Some bees produce honey from flower nectar. Honey bees and stingless bees commonly hoard large quantities of honey-a characteristic that is exploited by beekeepers, who harvest the honey for human consumption.
Food-Gathering Behavior of Bees (click to enlarge)

There are about 20,000 species of bees worldwide. Some species may not yet have been discovered, and many are either not named or have not been well studied. Bees are found throughout the world except at the highest altitudes, in polar regions, and on some small oceanic islands. The greatest diversity of bee species is found in warm, arid or semiarid areas, especially in the American Southwest and Mexico. Bees range in size from tiny species only 2 mm (0.08 in) in length to rather large insects up to 4 cm (1.6 in) long. Many bees are black or gray, but others are bright yellow, red, or metallic green or blue.

Social Structure and Nesting Habits Bees have diverse nesting and social habits. This diversity has provided scientists with a natural laboratory for the study of evolution and social behavior in insects.

Solitary Bees The primitive bees, like their relatives the wasps, are solitary. Each female makes her own burrow, in which she constructs earthen chambers to contain her young. She deposits pollen moistened with nectar or oil into individual cells until enough food has accumulated to provide for the young bee from egg hatching until the larva reaches full size. She then lays an egg on the pollen mass and seals the cell before going on to construct another cell.



Bees are adapted for feeding on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for larvae.
Bees have a long proboscis (a complex "tongue") that enables them to obtain the nectar from flowers. They have antennae almost universally made up of 13 segments in males and 12 in females, as is typical for the superfamily. Bees all have two pairs of wings, the hind pair being the smaller of the two; in a very few species, one sex or caste has relatively short wings that make flight difficult or impossible, but none are wingless.

The smallest bee is Trigona minima, a stingless bee whose workers are about 2.1 mm (5/64") long. The largest bee in the world is Megachile pluto, a leafcutter bee whose females can attain a length of 39 mm (1.5"). Members of the family Halictidae, or sweat bees, are the most common type of bee in the Northern Hemisphere, though they are small and often mistaken for wasps or flies.
The best-known bee species is the European honey bee, which, as its name suggests, produces honey, as do a few other types of bee. Human management of this species is known as beekeeping or apiculture.
Bees are the favorite meal of Merops apiaster, the bee-eater bird. Other common predators are kingbirds, mockingbirds, beewolves, and dragonflies.

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