Table 3.

Thorax temperatures (Tth) of worker bees inside three observation cells (setup B)

Observation time (min)Tth inside cell (°C)Tth at the beginning and at the end of cell visits (°C)
Ref. Total Inside cell Mean ± S.D. Range Int.Tth(entry)Tth(exit)Tth)net
Heat-producing bees
x329.829.337.8±1.534.3—39.434.438.3+3.9
x43.52.836.0±0.734.5—36.636.634.5—2.1
y165.363.3*39.0±1.035.3—40.62*37.7
38.438.7+0.3
38.038.1+0.1
y239.538.339.8±1.434.7—41.3140.339.1—1.2
39.537.6—1.9
y518.813.840.6±0.937.4—41.7139.240.6+1.4
40.137.4—2.7
z521.817.538.5±1.035.3—39.938.037.6—0.4
z616.815.040.3±0.737.7—41.137.739.6+1.9
z714.511.339.4±0.638.1—40.238.738.1—0.6
Resting bees
x29.84.832.7±0.132.2—32.8232.832.80.0
32.832.7—0.1
32.232.6+0.4
x87.56.332.7±0.132.2—33.032.732.9+0.2
x910.87.533.0±0.332.6—33.5133.533.0—0.5
32.832.7—0.1
z115.014.5*33.4±0.332.9—33.9*33.0
z218.312.832.7±0.232.2—32.832.732.2—0.5
Working bees
x118.311.834.7±1.432.9—38.310
x56.36.035.7±0.932.8—36.73
x149.38.334.2±0.732.8—36.04
• Ref.' refers to one of the three cells (x, y or z) and individual bees (characterized by ascending numbers) that were observed continuously. Missing numbers represent visits of ≤2 min. Visits that are marked with an asterisk lasted longer than the time that is indicated but were not recorded from the beginning. Tth was measured every 15 s. Thorax temperatures at the beginning and at the end of cell visits [Tth(entry) and Tth(exit), respectively] are also shown when a bee left and re-entered the same cell after a short interruption (data not shown for working bees). Int.' refers to the number of short interruptions if the cell visit was not continuous.