Body temperature and thermoregulation in two species of yellowjackets, Vespula germanica and V. maculifrons

SUMMARYBody temperature is a more pertinent variable to physiological stress than ambient air temperature. Modeling and empirical studies on the impacts of climate change on ectotherms usually assume that body temperature within organisms is uniform. However, many ectotherms show significant within-body temperature heterogeneity. The relationship between regional heterothermy and the response of ectotherms to sublethal and lethal conditions remains underexplored. We quantified withinbody thermal heterogeneity in an intertidal sea star (Pisaster ochraceus) during aerial exposure at low tide to examine the lethal and sublethal effects of temperatures of different body regions. In manipulative experiments, we measured the temperature of the arms and central disc, as well as survival and arm abscission under extreme aerial conditions. Survival was related strongly to central disc temperature. Arms were generally warmer than the central disc in individuals that survived aerial heating, but we found the reverse in those that died. When the central disc reached sublethal temperatures of 31-35°C, arms reached temperatures of 33-39°C, inducing arm abscission. The absolute temperature of individual arms was a poor predictor of arm abscission, but the arms lost were consistently the hottest at the within-individual scale. Therefore, the vital region of this sea star may remain below the lethal threshold under extreme conditions, possibly through water movement from the arms to the central disc and/or evaporative cooling, but at the cost of increased risk of arm abscission. Initiation of arm abscission seems to reflect a whole-organism response while death occurs as a result of stress acting directly on central disc tissues. Supplementary material available online at

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Survival and arm abscission are linked to regional heterothermy in an intertidal sea star

Pincebourde

Sanford

Helmuth

2013

“…Thermoregulation is widespread among large-bodied insects (Heinrich, 1993), particularly the Hymenoptera (Himmer, 1932), wasps (Coelho and Ross, 1996;Stabentheiner et al, 2004), solitary bees (Baird, 1986;Chappell, 1982;May and Casey, 1983;Nicolson and Louw, 1982;Stone, 1993a) and social bees (Bujok et al, 2002;Kleinhenz et al, 2003;Seeley et al, 2003;Stabentheiner et al, 1990;Starks and Gilley, 1999). Thermoregulation has significant ecological consequences (Corbet et al, 1993) because internal heat generation enables solitary (Stone, 1994) and social bees (Heinrich, 1993) to forage and pollinate under colder ambient conditions compared to animals that cannot actively thermoregulate.…”

mentioning

confidence: 99%

“…Engels et al (1995) observed workers gathering cerumen particles to plaster the glass covering an observation nest at the low temperature of 15°C. Interestingly, no evidence has been found that stingless bees use evaporative cooling (Fletcher and Crewe, 1981;Roubik and Peralta, 1983), a strategy used by honeybees (Lindauer, 1954) and wasps (Coelho and Ross, 1996). Ventilation appears to be the preferred strategy (Fletcher and Crewe, 1981;Roubik and Peralta, 1983;Zucchi and Sakagami, 1972) and may be sufficient to cool colonies under most circumstances, given the well-insulated nest structure (Engels et al, 1995;Rosenkranz et al, 1987).…”

mentioning

confidence: 99%

Effect of food quality, distance and height on thoracic temperature in the stingless beeMelipona panamica

Nieh

Sánchez

2005

Corrigendum Nieh, J. C. and Sánchez, D. Effect of food quality, distance and height on thoracic temperature in the stingless bee Melipona panamica. J. Exp. Biol. 208,[3933][3934][3935][3936][3937][3938][3939][3940][3941][3942][3943] On the title page of this paper, Daniel Sanchez was incorrectly affiliated to Division of Biological Sciences, Section of Ecology, Behavior, and Evolution, University of California San Diego, MC#0116, 9500 Gilman Drive, La Jolla, CA 92093-0116, USAThe correct affiliation should have read:El Colegio de la Frontera Sur, Carretera Antiguo Aeropuerto km 2.5, 30700 Tapachula, Chiapas, Mexico.We apologise for any inconvenience caused by this error. 3933Thermoregulation is widespread among large-bodied insects (Heinrich, 1993), particularly the Hymenoptera (Himmer, 1932), wasps (Coelho and Ross, 1996;Stabentheiner et al., 2004), solitary bees (Baird, 1986;Chappell, 1982;May and Casey, 1983;Nicolson and Louw, 1982;Stone, 1993a) and social bees (Bujok et al., 2002;Kleinhenz et al., 2003;Seeley et al., 2003;Stabentheiner et al., 1990;Starks and Gilley, 1999). Thermoregulation has significant ecological consequences (Corbet et al., 1993) because internal heat generation enables solitary (Stone, 1994) and social bees (Heinrich, 1993) to forage and pollinate under colder ambient conditions compared to animals that cannot actively thermoregulate.Several studies have found evidence for thoracic temperature regulation during honeybee recruitment (Esch, 1960;Stabentheiner, 2001;Stabentheiner and Hagmüller, 1991;Waddington, 1990). Honeybees can regulate their body temperature according to food quality, exhibiting higher thoracic temperatures after feeding at richer food sources (Schmaranzer and Stabentheiner, 1988;Underwood, 1991). Thoracic temperature positively correlates with the quality of the food as perceived by sweetness (Stabentheiner and Hagmüller, 1991), proximity to the nest (Esch, 1960;Stabentheiner, 1996) and nectar flow rate (Farina and Wainselboim, 2001). Moreover, thoracic temperatures are affected by the status of the hive (amount of pollen and nectar stores) and are thus tuned to colony need (Schulz et al., 1998). Mechanistically, honeybee thoracic temperature is tied to metabolic expenditure, which increases with increasing sugar concentration and nectar flow rate (Moffatt and Nunez, 1997), and perhaps with forager motivational state (Balderrama et al., 1992). Honeybee thoracic temperature is tied to the thermal stability and the ability to generate high mechanical power output in flight (Dudley, 2000;Woods et al., 2005).To date, no studies have examined whether stingless bees have similar thermal abilities. We therefore hypothesized that food profitability to the colony would significantly affect the temperatures of recruiting meliponine foragers at the feeder and inside the nest.What little is known about meliponine thermoregulation largely concerns the regulation of nest temperatures, not individual thermoregulation (Kerr and Laidlaw, 1956;Kerr et al., 1967;Michener, 1974;Roubik...

“…Such thermoregulation is widespread in Hymenoptera such as wasps (Coelho and Ross, 1996;Eckles et al, 2008), solitary bees (Baird, 1986;May and Casey, 1983;Stone, 1993) and social bees (Nieh et al, 2006;Nieh and Sánchez, 2005;Stabentheiner, 2001). This ability to thermoregulate is a valuable adaptation that has allowed honey bees to occupy wide altitudinal gradients (Heinrich, 1993) in which they are also important facilitators of plant gene flow (Kearns et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

Honey bee forager thoracic temperature inside the nest is tuned to broad-scale differences in recruitment motivation

Sadler

Nieh

2011

SUMMARYInsects that regulate flight muscle temperatures serve as crucial pollinators in a broad range of ecosystems, in part because they forage over a wide span of temperatures. Honey bees are a classic example and maintain their thoracic muscles at temperatures (T th ) tuned to the caloric benefits of floral resources. Using infrared thermography, we tested the hypothesis that forager motivation to recruit nestmates for a food source is positively correlated with T th . We trained bees to a sucrose feeder located 5-100m from the nest. Recruiting foragers had a significantly higher average T th (2.7°C higher) when returning from 2.5moll -1 sucrose (65% w/w) than when returning from 1.0moll -1 sucrose (31% w/w). Foragers exhibited significantly larger thermal fluctuations the longer they spent inside the nest between foraging trips. The difference between maximum and minimum temperatures during a nest visit (T range ) increased with total duration of the nest visit (0.7°C increase per additional min spent inside the nest). Bees that recruited nestmates (waggle or round danced) were significantly warmer, with a 1.4-1.5 times higher ⌬T th (difference between T th and nest ambient air temperature) than bees who tremble danced or simply walked on the nest floor without recruiting between foraging bouts. However, recruiter T th was not correlated with finer-scale measures of motivation: the number of waggle dance circuits or waggle dance return phase duration. These results support the hypothesis that forager T th within the nest is correlated to broad-scale differences in foraging motivation.