User:Simone.eloise/Worker bee

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A worker bee is any female bee that lacks the reproductive capacity of the colony's queen bee and carries out the majority of tasks needed for the functioning of the hive. While worker bees are present in all eusocial bee species, the term is rarely used (outside of scientific literature) for bees other than honey bees, particularly the European honey bee (Apis mellifera). Worker bees of this variety are responsible for approximately 80% of the world's crop pollination services.

Worker bees are the caste of bee that preform most of the fundamental tasks of the hive, and they are by far the most numerous type of bee. They are much smaller than drones or queen bees, with bodies specialized for nectar and pollen collection. They preform different tasks around the hive progressively over their lifespans in a predictable order based on their age.

Worker bees gather pollen in the pollen baskets on their back legs and carry it back to the hive where it is used as food for the developing brood. Pollen carried on their bodies may be transferred to another flower, where a small portion can rub off on the pistil, resulting in cross pollination. Nectar is sucked up through the proboscis, mixed with enzymes in the stomach, and carried back to the hive, where it is stored in wax cells and evaporated into honey.

Life Cycle
Honey bee workers maintain the hive temperature in the critical brood area where new bees are hatched and raised. Workers must maintain the hive's brood chamber within a range of 34-36 °C (93.2-96.8 °F). If the chamber becomes too hot, the workers collect water or diluted nectar and deposit it around the hive, then fan air with their wings to generate cooling by evaporation. If the chamber becomes too cold, worker bees can increase the temperature of their thoracic muscles using isometric contractions, pressing their warmed muscles against caps or walls of brood cells. In the wintertime, worker bees can cluster together to generate body heat to keep the brood area warm as external temperature decreases.

The life span of a worker bee fluctuates between the summer and winter months. In the summertime, worker bees typically only live two to six weeks compared to wintertime when workers can live up to 20 weeks. This reason for this difference lies in interior physiological processes that worker bees experience, and external factors, such as bees not leaving the relative safety of the hive during the colder winter months. Worker bees are exposed to a lot more risks during the summer months when they leave the hive to forage, and therefore have a shorter relative lifespan.

Honey bees begin as a egg laid by the queen in the brood nest, located near the center of the hive. Worker eggs are laid in smaller cells compared to drone eggs, and will hatch after three days into a larva. Nurse bees feed it royal jelly for three days, followed by pollen and honey for about two more days until the cell is capped by worker bees. The larvae spins itself into a cocoon and becomes an inactive pupa. During this 10 day stage, the bee begins to develop features such as eyes, wings, legs and other features that adult bees posses. After this 21 day developmental period, the adult bee will chew through its wax cap and cocoon and emerge into the hive as a fully grown bee, immediately beginning its roles in the hive.

Progression of Tasks
Through the lifecycle of a worker bee, she will take on many different roles within the hive, depending on how old she is and how long she has been working in the hive. The exact number of days she spends at each task depends on the requirements of the hive, however there is an estimated number of days each worker bee will spend at each task.

Honey production
Worker bees collect nectar from flowers using their tubular mouth parts, and store it in their honey stomach. Enzymes procede to break down the nectar into simple sugars. Back at the hive, the nectar is distributed to other worker bees who either distribute it to young bees or store it in honeycomb cells. Then, honey is produced by being further dehydrated via fanning then sealed with a wax cap, which prevents absorption of moisture from the air.

Drone feeding
Drones do not feed themselves when they are young; they are fed by workers and then when the drone bees get older they feed themselves from the honey supply.

Honeycomb building
Worker bees have eight pairs of wax glands under their abdomen from which they can create honeycomb. By chewing the wax, she mixes in her saliva which adjusts the maleability of the wax and enables her to create each individual honeycomb cell. This proces is repeated thousands of times to create comb in the hive, which will be used for honey production and brood space.

Pollen packing
Pollen brought into the hive for feeding the brood is also stored. It must be packed firmly into comb cells and mixed with a small amount of honey so that it will not spoil. Unlike honey, which does not support bacterial life, stored pollen will become rancid without proper care. It has to be kept in honey cells.

Propolizing
The walls of the hive are covered with a thin coating of propolis, a resinous substance obtained from plants. When workers add enzymes to the propolis, the combination has antibacterial and anti-fungal properties. Propolis is placed at the entrance of hives to aid in ventilation.

Some bees add excess mud to the mixture, making it geopropolis, such as in the bee Melipona scutellaris. Geopropolis displays antimicrobial and antiproliferative activity and has been proven to be a source of antibiofilm agents. It also presents selectivity against human cancer cell lines at low concentrations compared to normal cells.

Mortuary bees
Dead bees and failed larvae must be removed from the hive to prevent disease and allow cells to be reused. They will be carried some distance from the hive by mortuary bees.

Fanning bees
Worker bees fan the hive, cooling it with evaporated water. They direct airflow into the hive or out of the hive depending on need.

Water carriers
When the hive is in danger of overheating, these bees will obtain water, usually from within a short distance from the hive and bring it back to spread on the backs of fanning bees.

Guard bees
Guard bees will stand at the front of the hive entrance, defending it from any invaders such as wasps. The number of guards varies from season to season and from species to species. Entrance size and daily traffic also play an integral role in the number of guard bees present. Guard bees of the species Tetragonisca angustula and Schwarziana quadripunctata are examples of eusocial bees that have been observed hovering at their nest entrances, providing more protection against intruders.