Comparison of thermal traits of Polistes dominula and Polistes gallicus, two European paper wasps with strongly differing distribution ranges

Abstract

The two paper wasps, Polistes dominula and Polistes gallicus, are related species with strongly differing distribution ranges. We investigated thermal tolerance traits (critical thermal limits and metabolic response to temperature) to gain knowledge about physiological adaptations to their local climate conditions and to get evidence for the reasons of P. dominula’s successful dispersion. Body and ambient temperature measurements at the nests revealed behavioural adaptations to microclimate. The species differed clearly in critical thermal minimum (P. dominula −1.4 °C, P. gallicus −0.4 °C), but not significantly in critical thermal maximum of activity (P. dominula 47.1 °C, P. gallicus 47.6 °C). The metabolic response did not reveal clear adaptations to climate conditions. At low and high temperatures, the metabolic rate of P. dominula was higher, and at intermediate temperatures, we determined higher values in P. gallicus. However, the species exhibited remarkably differing thermoregulatory behaviour at the nest. On average, P. gallicus tolerated a thoracic temperature up to ~41 °C, whereas P. dominula already tried at ~37 °C to keep the thorax below ambient temperature. We suggest this to be an adaptation to the higher mean ambient temperature we measured at the nest during a breeding season. Although we determined for P. dominula a 0.5 °C larger thermal tolerance range, we do not presume this parameter to be solely responsible for the successful distribution of P. dominula. Additional factors, such as the thermal tolerance of the queens could limit the overwintering success of P. gallicus in a harsher climate.

The Respiratory Metabolism of Polistes biglumis, a Paper Wasp from Mountainous Regions

“…In contrast to the SMR, the upper thermal limit or CT max of activity we determined for Polistes biglumis (CT max = 47.2 • C) was virtually identical to that of Polistes dominula (CT max = 47.1 • C) [18]. This is a surprising result, as one would expect that the species living in a warmer habitat has been endowed with a higher thermal tolerance (upper thermal limit), as was determined in seed bug species [39].…”

“…The point of time when controlled motoric activity ceased and muscle spasms started was determined via behavioral observation, and the Insects 2020, 11, 165 5 of 12 temperature at that time (CT max ) was extracted from the logger file of a thermocouple, which was recording the temperature inside the measurement chamber. For further information see [13,18].…”

Adaptations to thermal stress in social insects: recent advances and future directions

“…In honeybee ( Apis mellifera ) populations adapted to colder climates, major energy‐producing mitochondrial pathways were found to be upregulated (Parker et al ., 2010). In both ants ( Aphaenogaster iberica ; Shik et al ., 2019) and wasps ( Polistes dominula , Kovac et al ., 2017), workers from populations found at higher altitudes had higher metabolic rates than did workers from populations found at lower altitudes.…”

“…Indeed, social insect species living in more mesic habitats further north were found to have a lower CT max than those living in more xeric habitats further south [ants (Marsh, 1985; Morton & Christian, 1994; Oberg, del Toro, & Pelini, 2012); bees (Ruttner, 1988; Abou‐Shaara, 2015); termites (Janowiecki et al ., 2019)]. Northern European species of Polistes wasps were found to have a lower CT min than species from the Mediterranean (Kovac et al ., 2017). Ants display within‐species variation in thermal tolerance: populations from higher latitudes were shown to have a lower CT min than populations from lower latitudes ( Leptothorax acervorum ; Heinze et al ., 1998).…”

The Thermoregulatory Behavior of Nectar Foraging Polistine Wasps (Polistes dominula and Polistes gallicus) in Different Climate Conditions

“…In general, in evolutionary adaptation processes species have developed special physiological features to cope with the environmental conditions of their habitat. In Polistes dominula and Polistes gallicus, it could be shown that these species have developed thermal traits according their thermal environment [10]. The aim of this study was to investigate the thermoregulatory behavior of these two closely related species in different habitats with differing climate, under special consideration of the microclimate conditions.…”