The Apis mellifera, commonly referred to as honey bees, are perhaps the most intensely studied of all insects. Their economic importance to the agricultural industry has driven the need for scientific research. As a result, a wealth of valuable and interesting information has accumulated. This mass of data has shown honey bees to be highly social creatures with complicated behaviors and intriguing population dynamics.
The economic importance of honey bees is due to the products they produce as well as services they perform. Although honey bees produce honey, they serve a more important role as pollinators. What makes the honey bee so special is that unlike many insects, the honey bee will seek out pollen and not nectar. Honey bees commonly pollinate agricultural crops such as apples, cherries, melons, and almonds. In fact, many farmers hire beekeepers to raise and maintain bee colonies on their farms entirely for this purpose. Honey bees also produce wax used for polishes and candles. The importance of honey bees is not a new discovery. Pictographs depicting bees and their hives have been found painted on the walls of caves believed to be many thousands of years old.
Rock painting depicting honey gathering. Discovered in the Cuevas de la Arana near Bicorp in Valencia, Spain, from E. Hernendez-Pacheco, Museo nacional de ciences naturales, Madrid
Although honey and bees play an enormous role in the United States agricultural industry, they are not native to North America. Interestingly, they were brought here by early European colonizers. The indigenous habitat of the Apis mellifera ranges from the tip of Southern Africa to Southern Scandinavia, and from continental Europe to Western Asia. Thus the honey bee is a highly adaptable insect able to adjust to a wide variety of climes and geographic regions.
The desert regions of the southwestern United States and northern Mexico are home to the richest variety of bees in all the world. According to the Carl Hayden Bee Research Center, located in Tucson, Arizona there are approximately 1000 to 1200 species of bees within a one hundred mile radius of Tucson. Yet, none of these are native honey bees.
Approximately 25,000 species of bees have been identified, with almost 40,000 still yet to be catalogued. That is, entomologists know that they are out there, but have yet to place them in a specific genus. However, out of this 25,000, only 8 to 10 species are considered honey bees. Yet, this number is growing as more species are identified.
Honey bees are not only classified by genus and species, but by strain. The strain denotes the bees' place of origin. The most common strains of honey bees currently found in the United States are the Apis mellifera ligustica, the Italian bees, and the Apis mellifera carnica, the Carniolan bees. However, many common lines of honey bees have been allowed to interbreed. The goal of such crossings has been to develop hybrid bees with specific morphological and behavioral traits that will enhance their honey producing and pollinating traits. The most famous attempt at creating such a hybridized line was the crossing of the European lines and the African lines.
The goal of crossing the European and the African lines was to mate the docile but high honey yield European bees with their aggressive but low yield African counterparts. In 1956, Brazilian researchers hoped that a harder working bee that made more honey would result. However, the experiment did not succeed. What the researchers found was that the aggressive traits dominated and essentially masked the European characteristics. The experiments have become famous because a worker in the apiary where the hybridized lines were being kept accidentally removed protective screens that kept the queens in their hives. As a result, at least 26 swarms of the Africanized bees escaped. The descendants have been moving northward ever since. Today. 40 years later, Africanized honey bees are found in the southwestern United States and are a cause for concern due to their aggressive nature, and their ability to take over and replace established colonies of productive European lines.
A major product of the general scientific research into the ecology of Apis Mellifera is a greater understanding of the honey bee's ``social structure'' and population dynamics. In examining the population of the colony, scientists have uncovered the existence of a highly ordered caste system. The queen reigns at the top of the caste, with the male drones and female workers below.
The queen's primary duties are to populate the colony by mating with drones (male honey bees), and direct the activities of the workers. The queen mates during the early summer months, generally within the first week after having emerged from her chamber. She takes what is referred to as ``nuptial flights'' where she may mate with several drones per day over the course of several days. She collects their sperm inside a large body cavity called the ``spermatheca.'' After this flight has been completed the queen has accumulated enough sperm to sustain her entire career as the egg-layer of the hive. However, if the queen's egg-laying capacity is deficient, or if she is unresponsive to the needs of the colony in some way, she may be attacked by the workers and replaced.
The workers are the second caste in the colony and perform many crucial tasks within the hive. Most importantly, they are responsible for tending to the queen by bringing to her a special food, and grooming her. Additionally, workers build comb, tend the brood, seal and cap comb cells containing either honey or bees, remove debris from the hive, store pollen, ripen and store honey, and guard the hive.
The male drones are the third caste in the colony. They are responsible for mating with queens from other colonies and perform virtually no other useful task within the hive. After mating, drones die from the rupturing of their abdomens and genital apparatus. However, many drones die before they get a chance to mate with the queen because they may be killed or thrown out of the nest by worker bees when food resources are low.
Examining the behavior and ecology of bees is a worthy task. Bees are important economically as well as ecologically. By understanding their behavior, morphology, and population dynamics, scientists, beekeepers, and farmers may work together to develop strategies that enhance the productivity of our agricultural industries.