Аn infrared thermal survey application on a thermal budget investigation of nests of Formica aquilonia Yarrow, 1955 (Hymenoptera: Formicidae)

The mechanism of the heat generation into nests of red wood ants attracts attention of researchers for a long time. The emergence of new technical means of measurement allows to study this problem more detailed. In Kurortny District of St. Petersburg (Russia), air temperature and temperature on surface and inside of the nest Formica aquilonia Yarrow, 1955 were measured during the period of ants offspring breeding. At various times of the day we made registrations of nests temperature by infrared imager, accompanied by continuous measurement of characteristics of the surface layer of air. Then, the upper part of nests has been removed and we held digital photo and thermal recording of its interior part. Mathematical modeling of the expected thermal effects was done. According to the results of observations and subsequent calculations, heat losses via mounds surface of nest were 9.2 ± 1 W. Mathematical modeling has shown that for ensuring of observed rate of warming of nests in spring an internal heat source with a power ~20 W is required For this, worker ants have to spend 0.5-1% of their total weight in the form of stored sugars. Correlation analysis of individuals’ density inside of nest and its temperature showed that the metabolic heat is the main source of energy for maintenance of high temperatures of nest

The significance of latitudinal variation in body size in a holarctic ant, Leptothorax acervorum. Ecography 26:349–355

The mean body size of workers of the holarctic ant Leptothorax acer6orum increases with latitude. Workers from populations near the Polar Circle were 10% larger than workers from central Europe. This gradient does not appear to be associated with variation in colony size. According to controlled rearing experiments with brood from populations in Cape Kartesh, Karelia (67°N) and Erlangen, Germany (49.7°N), larger adult body size in boreal populations is not an epiphenomenon of slow cell growth and larger cell size at lower temperatures. Larger workers survived longer without food both at room temperature and B0°C, suggesting that selection for increased fasting endurance in boreal habitats might lead to this Bergmann's rule-like pattern in an ectothermic ant