Comparison of signal production and foraging activity in three pairs of genetically diverse and genetically uniform colonies, over 3 days of observation per pair. (Total number of signals produced per day were determined by counting signals observed on the dance floor of hives during the first minute of every 5-min interval of observation (waggle dances were counted from 07.00 to 19.00; shaking signals were counted from 07.00 to 08.00). Relative foraging rates were determined from 12.00 to 12.30. Means, s.e. and s.d. were calculated using 3-day colony means; percentage of increase=((genetically diverse−genetically uniform)/genetically uniform)×100%.)