English: Occurrence of CNRs. IR monitoring of experimental “nest 02” (cf. Fig 1) through 33 min at 3.9427 Hz. The temperature scale on the right is fixed between 26° and 40°C, whereby the range of the actual temperature pixels is displayed by the small bar between the scale partition and the rainbow-900 palette. The black bar at the bottom displays the relative time of the image noted in minutes. The blue-green areas represent CNRs while the tiny red spots regard to the interstices between the bees of the surface layer; according to the ventilation hypothesis they document the “exhalation” phase when nest-warm air is pressed out through the diffuse mesh of the curtain (cf. Fig 7).