An experimental box (4 5 10 cm) was attached between the nest and the entrance to the nest by plastic tubes. The experimental box was also covered by a glass sheet, which allowed an observer to watch the interactions of the bees inside the box. A small introduction tube (3 cm height 1 cm diameter) was inserted into the side of the experimental box to allow introduction of experimental bees into the experimental box with minimal disturbance to the resident bees. The introduction tube was opened to the interior of the experimental box and sealed at the other exit by a removable cork.