The influence of small-cell brood combs on the morphometry of honeybees (Apis mellifera)

Until the late 1800s honeybees in Britain and Ireland were raised in brood cells of circa 5.0 mm width. By the 1920s this had increased to circa 5.5 mm. We undertook this study to find out if present-day honeybees could revert to the cell-size of the 1800s and to evaluate resulting changes in honeybee morphometry. Seven measurements were made; head width, radial cell length, trachea diameter, cubital index, discoidal shift, bee mass and abdominal markings. The study showed that the colonies of Apis mellifera mellifera bees had no apparent difficulty in drawing out the wax and raising brood in the reduced brood cells. Bees reared in these cells were significantly smaller, but this reduction was not in proportion (< 20%) to the change in the brood-cell size in contrast to the strongly proportional relationship in other bee strains. Also the ratio of thorax width to cell width ('fill factor') was much larger in the Apis mellifera mellifera strain.