Caste

Definition

Queen and worker honey bees are genetically identical as eggs; the difference is diet, with queen larvae fed royal jelly throughout development. That produces an animal with functioning ovaries, a different body shape and a lifespan of years rather than weeks. Drones develop from unfertilised eggs and are haploid. In bumblebees the caste separation is much less sharp, and in primitively eusocial bees such as some sweat bees the queen looks almost identical to her workers.

Where the word gets used loosely

Caste is often described as rigid and predetermined. Within honey bees it is determined by feeding rather than genetics, and workers can and do raise a new queen from an ordinary female egg when they need to.

Honey records that discuss this

• Jataí honeySharply acidic and fruity with a fermented tang — closer to a sharp fruit syrup than to what most people expect honey to taste like.

Bee records that discuss this

• Sharp-collared furrow beeA small sweat bee that is one of the best-studied examples of primitive eusociality anywhere. A single foundress produces a first brood of small workers who forage for her, and only later are reproductive females produced — a genuine caste system without the sharp physical separation honey bees show, and one that switches on and off with latitude.
• Vestal cuckoo bumblebeeThe commonest cuckoo bumblebee in southern Britain, and a specialist parasite of the buff-tailed bumblebee. A female invades an established colony, kills or subdues the resident queen, and the host workers then raise her offspring — which means the host colony's own reproduction ends entirely.

Guide records that discuss this

• The honey bee lifecycleEvery honey bee passes through egg, larva, pupa and adult, and the timing differs by caste in ways that decide almost everything about how a colony works — including why the varroa mite is so difficult to control.
• Royal jelly and how a queen is madeA glandular secretion that turns a genetically ordinary larva into a queen. What it does inside the hive is remarkable and well established; what it does in a capsule is neither.