New studies are slowly shedding light on the important role that genes and environment play in bee behaviour. It has long been known that the queen has two X chromosomes and retains the male sperm after mating. She fertilises eggs only when the need arises to produce new nymph queens. This leads to swarming, with queen and bees leaving the hive to establish a colony elsewhere. The males are not the result of sexual mating and they contain only half a set of chromosomes. Workers are sterile females arising from an asexual process.
It has been said that we are all the result of nature and nurture; that is, our inherited genetic potential and environmental factors during our development, and the interaction between them. The same applies to bees. During the first two weeks of life, worker bees are engaged in brood duties inside the hive: cleaning, fanning the air, building the honeycomb structure, feeding the young and carrying out the dead bees. During the remaining five to seven weeks of their lives, workers become foragers. Some will focus on gathering pollen, which will be mixed with secreted wax for building the comb. Others will focus on gathering nectar, which will become honey after it is regurgitated at the hive.
Genetic studies and brain analysis at individual bee level have shown the important roles of gene expression and environment. A hormone produced by the queen activates the gene expression that favours nursing behaviour. A specific gene was identified as the major player in determining social change from nurse worker to forager. New diagnostics now enable scientists to study thousands of gene expressions at the same time. A better understanding of genes, environment and social bee behaviour could be helpful in beekeeping and in using bees as pollinators in seed production of crops such as hybrid sunflowers and onions. It also serves to promote understanding of gene expression in humans, specifically genes involved in different types of cancers.
Pollination is fundamental to sexual production in plants, and in bee-pollinated plants it has resulted in plant-animal co-evolution. Nectar and copious pollen production are the cost to the plant for its services of the inadvertent pollinator. Most bees are pollinators and they are attracted to flowers for food.
Plants are fundamental to terrestrial life as primary producers, and they maintain watersheds, prevent soil erosion, and provide shelter, refugia (places of refuge from which organisms re-colonize distributed areas), food, nesting sites and useful materials for many animals and man. Pollination is therefore essential for agriculture and environmental management, and a variety of pollinators are required to maintain reproduction across a broad spectrum of plant species. As the cost for pollination is the production of nectar and excessive pollen by plants, the maintenance of refugia are the cost of pollination to land users.