About 130 million years ago, when the first flowering plants evolved, it is believed that some wasps diversified and started feeding their grubs on pollen which is full of protein and highly nutritious, instead of their usual diet of chewed up insects. And it is believed that these wasps evolved into the bees.
1. Individuals of the same species co-operate in caring for the young.
2. There is a reproductive division of labour.
3. There is an overlap of at least 2 generations in life stages capable of contributing to colony behaviour.
Bees, whether social or solitary, eat pollen and nectar all their lives. So bees need flowers, and many flowers cannot breed without the pollinating ability of bees. In California every year about 1,000,000 hives (about 10 billion bees in all) are transported in from other parts of the US just to pollinate the almond crop in February.
Plants reward their pollinators with nectar - it has no other use. Most bees carry the nectar in their stomach (bumblebee honeystomach) and regurgitate it in the nest or hive.
Some species store the nectar, which with the evaporation of some water and the addition of enzymes from the bee's stomach, becomes what we know as honey.
Pollen is carried home either in pollen baskets on the bee's hind pair of legs, or on thick hairs on the undersides of the abdomen, as in the leafcutters.
The Apis mellifera (honeybee) genome has been published recently. It is the fourth insect to have its genome sequenced, the others are the mosquito, fruit fly and the silk moth.
The colour of honeybees varies according to the species, but is usually brown and covered in brown/gray hairs. The honeybee is not nearly as hairy as the bumblebee. The body of the queen honeybee is similar to that of the workers, but she is a little larger.
Bees were sacred to the ancient Egyptians. They believed bees descended from the tears of Ra, the sun god, as he landed on earth. The bee was a symbol of kinship, and jars of honey were placed in tombs to aid the journey of the departed into the next life.
The drawing above is the antenna of a female bee, the male antenna is the same except it has an extra segment on the flagellum.