... the differing capacities of lizards to depress body temperature ( T b ) through evaporative cooling via panting. Here, we link panting and T b depression with rates of evaporative water loss and its metabolic costs under high heat loads. We used flow-through respirometry to measure evaporative water loss rates...

... cliffs. We used flow-through respirometry to measure the response of body temperature, resting metabolic rate, evaporative water loss and evaporative cooling efficiency (the ratio of evaporative heat loss to metabolic heat production) in murres while experimentally increasing air temperature. Murres had...

... ), evaporative water loss (EWL) and resting metabolic rate (RMR) measured under standardized conditions of very low humidity in 56 arid-zone species. Maximum T b during acute heat exposure varied from 42.5±1.3°C in caprimulgids to 44.5±0.5°C in passerines. Among passerines, both maximum T b and the difference...

... the body temperature ( T b ) at VT max , and duration of heating, between two source groups with different thermal histories, and among three reproductive groups. We also examined continuous changes in T b (via an attached biologger) and total evaporative water loss (EWL) during heating. In the field, we...

...Christine Elizabeth Cooper; Philip Carew Withers; Gerhard Körtner; Fritz Geiser ABSTRACT Insensible evaporative water loss (EWL) at or below thermoneutrality is generally assumed to be a passive physical process. However, some arid zone mammals and a single arid zone bird can control...

... (mean maximum ambient temperature=42.7°C) and cooler (mean maximum ambient temperature=31.4°C) periods during a single Austral summer. We measured body mass, metabolic rate, evaporative water loss and body temperature, along with blood parameters (corticosterone, glucose and uric acid) of wild zebra...

... temperature ( T b ). Whereas diurnal birds can potentially rehydrate throughout the day, nocturnal species typically forgo drinking between sunrise and sunset. We hypothesized that nocturnal birds have evolved reduced rates of evaporative water loss (EWL) and more economical evaporative cooling mechanisms...

... primates preadapted for no good reason to making fabulously complicated twigs with which to fish out delicious and entertaining nuggets from the termite mound of consensual reality .’ Respiration Metabolic downregulation Evaporative water loss Environmental adaptation Complex systems Emergent...

... kennicottii ), which occupy the Sonoran Desert of southwestern North America, an area of extreme heat and aridity. We exposed wild-caught birds to progressively increasing air temperatures ( T a ) and measured resting metabolic rate (RMR), evaporative water loss (EWL), body temperature ( T b ) and heat...

... in resting metabolic rate above clearly defined upper critical limits of thermoneutrality and increases in evaporative water loss to levels equivalent to 700–1000% of baseline rates at thermoneutral T a . Maximum cooling capacity, quantified as the fraction of metabolic heat production dissipated...

... dissipation by evaporative water loss (EWL) through the respiratory tract. We asked to what extent this response was apparent at the earliest stages of development, when pulmonary ventilation initiates. Measurements of pulmonary ventilation ( V̇ E ; barometric technique), V̇ O 2 (open-flow methodology...

... metabolic rate (RMR), evaporative water loss (EWL), body temperature ( T b ) and heat tolerance limit (HTL; the maximum T a reached). Comparatively low RMR values were observed in all species (0.35, 0.36 and 0.40 W for the poorwill, nighthawk and owlet-nightjar, respectively), with T b approximating T...

... cardinal, Abert's towhee and curve-billed thrasher. Using flow-through respirometry, we measured daytime resting metabolism, evaporative water loss and body temperature at air temperatures ( T air ) between 30 and 52°C. We found marked increases in resting metabolism above the upper critical temperature...

... of thermoneutrality and increases in evaporative water loss (EWL) to levels equivalent to 670–860% of baseline rates at thermoneutral T a . Maximum cooling capacity, quantified as the fraction of metabolic heat production dissipated evaporatively, ranged from 1.20 to 2.17, consistent with the known range...

... minimum body temperature of 38.5±0.04°C that was independent of minimum black bulb temperature. Physiological variables measured in the laboratory revealed that babblers had a low basal metabolic rate and evaporative water loss, but their body temperature and thermal conductance were typical of those...

...) and evaporative water loss (EWL) at T a between 25°C and ∼58°C in birds exposed to successive increments in T a . Normothermic T b averaged 39.0°C, lower than typical avian values. At T a >34.5°C, T b increased linearly to a maximum of 43.6°C at T a =56°C. The upper critical limit of thermoneutrality ( T uc...

...Sasha Ayton; Sean Tomlinson; Ryan D. Phillips; Kingsley W. Dixon; Philip C. Withers ABSTRACT Seasonal acclimatisation of thermal tolerance, evaporative water loss and metabolic rate, along with regulation of the hive environment, are key ways whereby hive-based social insects mediate climatic...

... measured resting metabolic rate (RMR) and total evaporative water loss (TEWL) using open flow-through respirometry, and core body temperature ( T b ) using passive integrated transponder tags. Sparrow-weavers were exposed to a ramped profile of progressively higher T a between 30 and 52°C to elicit maximum...

... to increasing temperatures, we examined thermoregulatory performance and estimated heat tolerance limits (HTLs) for three Sonoran Desert nesting bird species – Gambel's quail, mourning doves and white-winged doves. Using flow-through respirometry we measured daytime resting metabolism, evaporative water loss...

... a birds tolerated ranged from 48°C to 54°C, and was positively related to M b . Values of T b associated with severe heat stress were in the range of 44 to 45°C. Rates of evaporative water loss (EWL) increased rapidly when T a exceeded T b , and maximum evaporative heat dissipation was equivalent to 141...