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David L. Swanson - One of the best experts on this subject based on the ideXlab platform.
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Physiological Responses to Temperature by Whip-Poor-Wills: More Evidence for the Evolution of Low Metabolic Rates in Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiológicas de Caprimulgus vociferus a la Temperatura: Más Evidencia a Favor de la Evolución de una Baja Tasa Metabólica en Caprimúlgidos Resumen. Medimos las respuestas metabólicas a aumentos de la temperatura ambiental en un rango de 0–40°C en nueve individuos de Caprimulgus vociferus capturados en Dakota del Sur. De manera similar a otros Caprimúlgidos, C. vociferus presentó una tasa metabólica basal menor a la predicha por parámetros alométricos. Comparamos las tasas metabólicas basales de seis especies de caprimúlgidos (nuestros datos más datos publicados para otras cinco especies) con aquellas de otras 82 especies de aves utilizando aná lisis de co-varianza (ANCOVA) convencionales y filogenéticamente independientes. La baja tasa metabó lica basal de los caprimúlgidos no fue explicada por su posición filogenética. La baja tasa metabólica basal, junto a la capacidad generalizada de las aves de este orden de usar torpor diario, aparentemente han permitido a los miembros de este grupo a ocupar un nicho ecológico único (insectivoría crepuscular).
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PHYSIOLOGICAL RESPONSES TO TEMPERATURE BY WHIP-POOR-WILLS: MORE EVIDENCE FOR THE EVOLUTION OF LOW METABOLIC RATES IN Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiologicas de Caprimulgus vociferus a la Temperatura: Mas Evidencia a Favor de la Evolucion de una Baja Tasa Metabolica en C...
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Daily torpor in free-ranging whip-poor-wills (Caprimulgus vociferus).
Physiological and biochemical zoology : PBZ, 2004Co-Authors: Jeffrey E. Lane, R. Mark Brigham, David L. SwansonAbstract:The use of heterothermy is well documented in the order Caprimulgiformes, but there is conflicting information regarding whether whip-poor-wills are heterothermic. Consequently, we sought to rigorously examine the thermoregulatory abilities of this species. Our study was conducted in southeast South Dakota (4247N, 970W), where 35 individuals were captured and outfitted with external, temperature-sensitive radio transmitters. We found evidence that whip-poor-wills used daily torpor during the autumn of 2000 and the spring of 2001 ( torpor bouts, based on 346 bird-nights of observation). n p 12
Andrew E. Mckechnie - One of the best experts on this subject based on the ideXlab platform.
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Avian thermoregulation in the heat: evaporative cooling capacity of arid-zone Caprimulgiformes from two continents.
Journal of Experimental Biology, 2017Co-Authors: William A Talbot, Andrew E. Mckechnie, Todd J Mcwhorter, Alexander R Gerson, Blair O WolfAbstract:ABSTRACT Birds in the order Caprimulgiformes (nightjars and allies) have a remarkable capacity for thermoregulation over a wide range of environmental temperatures, exhibiting pronounced heterothermy in cool conditions and extreme heat tolerance at high environmental temperatures. We measured thermoregulatory responses to acute heat stress in three species of Caprimulgiformes that nest in areas of extreme heat and aridity, the common poorwill ( Phalaenoptilus nuttallii : Caprimulgidae) and lesser nighthawk ( Chordeiles acutipennis : Caprimulgidae) in the Sonoran Desert of Arizona, and the Australian owlet-nightjar ( Aegotheles cristatus : Aegothelidae) in the mallee woodlands of South Australia. 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 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 a at 40°C and mild hyperthermia occurring as T a reached the HTL. Nighthawks and poorwills reached HTLs of 60 and 62°C, respectively, whereas the owlet-nightjar had a HTL of 52°C. RMR increased gradually above minima at T a of 42, 42 and 35°C, and reached 1.7, 1.9 and 2.0 times minimum resting values at HTLs in the poorwill, nighthawk and owlet-nightjar, respectively. EWL increased rapidly and linearly as T a exceeded T b and resulted in maximum rates of evaporative heat dissipation equivalent to 237–424% of metabolic heat production. Bouts of gular flutter resulted in large transient increases in evaporative heat loss (50–123%) accompanied by only small increments in RMR ( T b well below T a in extreme heat and is comparable to the efficient cooling observed in arid-zone columbids in which cutaneous EWL is the predominant cooling pathway.
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Avian thermoregulation in the heat: evaporative cooling capacity of arid-zone Caprimulgiformes from two continents.
The Journal of experimental biology, 2017Co-Authors: William A Talbot, Andrew E. Mckechnie, Todd J Mcwhorter, Alexander R Gerson, Blair O WolfAbstract:Birds in the order Caprimulgiformes (nightjars and allies) have a remarkable capacity for thermoregulation over a wide range of environmental temperatures, exhibiting pronounced heterothermy in cool conditions and extreme heat tolerance at high environmental temperatures. We measured thermoregulatory responses to acute heat stress in three species of Caprimulgiformes that nest in areas of extreme heat and aridity, the common poorwill (Phalaenoptilus nuttallii: Caprimulgidae) and lesser nighthawk (Chordeiles acutipennis: Caprimulgidae) in the Sonoran Desert of Arizona, and the Australian owlet-nightjar (Aegotheles cristatus: Aegothelidae) in the mallee woodlands of South Australia. We exposed wild-caught birds to progressively increasing air temperatures (Ta) and measured resting metabolic rate (RMR), evaporative water loss (EWL), body temperature (Tb) and heat tolerance limit (HTL; the maximum Ta 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 Tb approximating Ta at 40°C and mild hyperthermia occurring as Ta reached the HTL. Nighthawks and poorwills reached HTLs of 60 and 62°C, respectively, whereas the owlet-nightjar had a HTL of 52°C. RMR increased gradually above minima at Ta of 42, 42 and 35°C, and reached 1.7, 1.9 and 2.0 times minimum resting values at HTLs in the poorwill, nighthawk and owlet-nightjar, respectively. EWL increased rapidly and linearly as Ta exceeded Tb and resulted in maximum rates of evaporative heat dissipation equivalent to 237-424% of metabolic heat production. Bouts of gular flutter resulted in large transient increases in evaporative heat loss (50-123%) accompanied by only small increments in RMR (
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Physiological Responses to Temperature by Whip-Poor-Wills: More Evidence for the Evolution of Low Metabolic Rates in Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiológicas de Caprimulgus vociferus a la Temperatura: Más Evidencia a Favor de la Evolución de una Baja Tasa Metabólica en Caprimúlgidos Resumen. Medimos las respuestas metabólicas a aumentos de la temperatura ambiental en un rango de 0–40°C en nueve individuos de Caprimulgus vociferus capturados en Dakota del Sur. De manera similar a otros Caprimúlgidos, C. vociferus presentó una tasa metabólica basal menor a la predicha por parámetros alométricos. Comparamos las tasas metabólicas basales de seis especies de caprimúlgidos (nuestros datos más datos publicados para otras cinco especies) con aquellas de otras 82 especies de aves utilizando aná lisis de co-varianza (ANCOVA) convencionales y filogenéticamente independientes. La baja tasa metabó lica basal de los caprimúlgidos no fue explicada por su posición filogenética. La baja tasa metabólica basal, junto a la capacidad generalizada de las aves de este orden de usar torpor diario, aparentemente han permitido a los miembros de este grupo a ocupar un nicho ecológico único (insectivoría crepuscular).
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PHYSIOLOGICAL RESPONSES TO TEMPERATURE BY WHIP-POOR-WILLS: MORE EVIDENCE FOR THE EVOLUTION OF LOW METABOLIC RATES IN Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiologicas de Caprimulgus vociferus a la Temperatura: Mas Evidencia a Favor de la Evolucion de una Baja Tasa Metabolica en C...
Jeffrey E. Lane - One of the best experts on this subject based on the ideXlab platform.
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Physiological Responses to Temperature by Whip-Poor-Wills: More Evidence for the Evolution of Low Metabolic Rates in Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiológicas de Caprimulgus vociferus a la Temperatura: Más Evidencia a Favor de la Evolución de una Baja Tasa Metabólica en Caprimúlgidos Resumen. Medimos las respuestas metabólicas a aumentos de la temperatura ambiental en un rango de 0–40°C en nueve individuos de Caprimulgus vociferus capturados en Dakota del Sur. De manera similar a otros Caprimúlgidos, C. vociferus presentó una tasa metabólica basal menor a la predicha por parámetros alométricos. Comparamos las tasas metabólicas basales de seis especies de caprimúlgidos (nuestros datos más datos publicados para otras cinco especies) con aquellas de otras 82 especies de aves utilizando aná lisis de co-varianza (ANCOVA) convencionales y filogenéticamente independientes. La baja tasa metabó lica basal de los caprimúlgidos no fue explicada por su posición filogenética. La baja tasa metabólica basal, junto a la capacidad generalizada de las aves de este orden de usar torpor diario, aparentemente han permitido a los miembros de este grupo a ocupar un nicho ecológico único (insectivoría crepuscular).
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PHYSIOLOGICAL RESPONSES TO TEMPERATURE BY WHIP-POOR-WILLS: MORE EVIDENCE FOR THE EVOLUTION OF LOW METABOLIC RATES IN Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiologicas de Caprimulgus vociferus a la Temperatura: Mas Evidencia a Favor de la Evolucion de una Baja Tasa Metabolica en C...
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Daily torpor in free-ranging whip-poor-wills (Caprimulgus vociferus).
Physiological and biochemical zoology : PBZ, 2004Co-Authors: Jeffrey E. Lane, R. Mark Brigham, David L. SwansonAbstract:The use of heterothermy is well documented in the order Caprimulgiformes, but there is conflicting information regarding whether whip-poor-wills are heterothermic. Consequently, we sought to rigorously examine the thermoregulatory abilities of this species. Our study was conducted in southeast South Dakota (4247N, 970W), where 35 individuals were captured and outfitted with external, temperature-sensitive radio transmitters. We found evidence that whip-poor-wills used daily torpor during the autumn of 2000 and the spring of 2001 ( torpor bouts, based on 346 bird-nights of observation). n p 12
Julia A. Clarke - One of the best experts on this subject based on the ideXlab platform.
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Podargiform Affinities of the Enigmatic Fluvioviridavis platyrhamphus and the Early Diversification of Strisores (“Caprimulgiformes” + Apodiformes)
PloS one, 2011Co-Authors: Sterling J. Nesbitt, Daniel T. Ksepka, Julia A. ClarkeAbstract:Background The early Eocene Green River Formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. We identify the basal-most member of Podargiformes (extant and fossil stem lineage frogmouths) based on a new specimen of Fluvioviridavis platyrhamphus, a unique neoavian bird from the Fossil Butte Member of the Green River Formation of Wyoming. Extant frogmouths (Podargidae) comprise approximately 13 nocturnal species with an exclusively Australasian distribution. Methodology/Principal Findings The new specimen was included in a combined phylogenetic analysis of morphological (osteology and soft tissue) and molecular sequence (cytochrome b, c-myc exon 3, and RAG) data sampling species-level taxa from both extant and extinct members of Steatornithidae, Podargidae, Caprimulgidae, Nyctibiidae, Aegothelidae, and Apodiformes ( = Strisores). New data from F. platyrhamphus help resolve phylogenetic relationships within Strisores, supporting placement of F. platyrhamphus and the European fossil form Masillapodargus longipes as basal parts of Podargiformes and also supporting a sister taxon relationship between Podargiformes and Steatornithiformes (oilbirds) within Strisores. This relationship is recovered only when fossil taxa are included, reaffirming the potential impact of stem fossil taxa on inferences of phylogenetic relationships. The well-preserved mandible and palate of the new specimen demonstrate that many of the unique characteristics of the skull that characterize the crown frogmouth clade Podargidae arose early in the evolutionary history of the clade, over 50 million years ago. Comparisons with the new specimen also indicate that Eurofluvioviridavis and Fluvioviridavis are not closely related. Conclusions/Significance Together with the European fossil frogmouth Masillapodargus, Fluvioviridavis shows that Podargiformes had a much wider geographic distribution in the past, whereas extant species are restricted to Australasia. The Eocene record of Strisores from the Green River Formation and Messel Formation indicates most major subclade divergences had already occurred by the early-middle Eocene.
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podargiform affinities of the enigmatic fluvioviridavis platyrhamphus and the early diversification of strisores Caprimulgiformes apodiformes
PLOS ONE, 2011Co-Authors: Sterling J. Nesbitt, Daniel T. Ksepka, Julia A. ClarkeAbstract:Background The early Eocene Green River Formation avifauna preserves exceptional exemplars of the earliest unambiguous stem representatives of many extant avian clades. We identify the basal-most member of Podargiformes (extant and fossil stem lineage frogmouths) based on a new specimen of Fluvioviridavis platyrhamphus, a unique neoavian bird from the Fossil Butte Member of the Green River Formation of Wyoming. Extant frogmouths (Podargidae) comprise approximately 13 nocturnal species with an exclusively Australasian distribution. Methodology/Principal Findings The new specimen was included in a combined phylogenetic analysis of morphological (osteology and soft tissue) and molecular sequence (cytochrome b, c-myc exon 3, and RAG) data sampling species-level taxa from both extant and extinct members of Steatornithidae, Podargidae, Caprimulgidae, Nyctibiidae, Aegothelidae, and Apodiformes ( = Strisores). New data from F. platyrhamphus help resolve phylogenetic relationships within Strisores, supporting placement of F. platyrhamphus and the European fossil form Masillapodargus longipes as basal parts of Podargiformes and also supporting a sister taxon relationship between Podargiformes and Steatornithiformes (oilbirds) within Strisores. This relationship is recovered only when fossil taxa are included, reaffirming the potential impact of stem fossil taxa on inferences of phylogenetic relationships. The well-preserved mandible and palate of the new specimen demonstrate that many of the unique characteristics of the skull that characterize the crown frogmouth clade Podargidae arose early in the evolutionary history of the clade, over 50 million years ago. Comparisons with the new specimen also indicate that Eurofluvioviridavis and Fluvioviridavis are not closely related. Conclusions/Significance Together with the European fossil frogmouth Masillapodargus, Fluvioviridavis shows that Podargiformes had a much wider geographic distribution in the past, whereas extant species are restricted to Australasia. The Eocene record of Strisores from the Green River Formation and Messel Formation indicates most major subclade divergences had already occurred by the early-middle Eocene.
R. Mark Brigham - One of the best experts on this subject based on the ideXlab platform.
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Physiological Responses to Temperature by Whip-Poor-Wills: More Evidence for the Evolution of Low Metabolic Rates in Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiológicas de Caprimulgus vociferus a la Temperatura: Más Evidencia a Favor de la Evolución de una Baja Tasa Metabólica en Caprimúlgidos Resumen. Medimos las respuestas metabólicas a aumentos de la temperatura ambiental en un rango de 0–40°C en nueve individuos de Caprimulgus vociferus capturados en Dakota del Sur. De manera similar a otros Caprimúlgidos, C. vociferus presentó una tasa metabólica basal menor a la predicha por parámetros alométricos. Comparamos las tasas metabólicas basales de seis especies de caprimúlgidos (nuestros datos más datos publicados para otras cinco especies) con aquellas de otras 82 especies de aves utilizando aná lisis de co-varianza (ANCOVA) convencionales y filogenéticamente independientes. La baja tasa metabó lica basal de los caprimúlgidos no fue explicada por su posición filogenética. La baja tasa metabólica basal, junto a la capacidad generalizada de las aves de este orden de usar torpor diario, aparentemente han permitido a los miembros de este grupo a ocupar un nicho ecológico único (insectivoría crepuscular).
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PHYSIOLOGICAL RESPONSES TO TEMPERATURE BY WHIP-POOR-WILLS: MORE EVIDENCE FOR THE EVOLUTION OF LOW METABOLIC RATES IN Caprimulgiformes
The Condor, 2004Co-Authors: Jeffrey E. Lane, David L. Swanson, R. Mark Brigham, Andrew E. MckechnieAbstract:Abstract We measured the metabolic responses of nine Whip-poor-wills (Caprimulgus vociferus), captured in southeast South Dakota, to incremental changes in ambient temperature within the range of 0–40°C. Similar to other members of the Caprimulgiformes, Whip-poor-wills exhibited a basal metabolic rate that was lower than predicted by allometry. We compared basal metabolic rates of six caprimulgiform species (our data plus published values for five other species) with those of 82 other avian species using both conventional and phylogenetically independent ANCOVAs. The low basal metabolic rate of Caprimulgiformes was not explained by phylogenetic position. A low basal metabolic rate, together with the widespread ability of birds in this order to use daily torpor, seemingly has enabled members of this group to occupy their unique ecological niche (crepuscular insectivory). Respuestas Fisiologicas de Caprimulgus vociferus a la Temperatura: Mas Evidencia a Favor de la Evolucion de una Baja Tasa Metabolica en C...
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Daily torpor in free-ranging whip-poor-wills (Caprimulgus vociferus).
Physiological and biochemical zoology : PBZ, 2004Co-Authors: Jeffrey E. Lane, R. Mark Brigham, David L. SwansonAbstract:The use of heterothermy is well documented in the order Caprimulgiformes, but there is conflicting information regarding whether whip-poor-wills are heterothermic. Consequently, we sought to rigorously examine the thermoregulatory abilities of this species. Our study was conducted in southeast South Dakota (4247N, 970W), where 35 individuals were captured and outfitted with external, temperature-sensitive radio transmitters. We found evidence that whip-poor-wills used daily torpor during the autumn of 2000 and the spring of 2001 ( torpor bouts, based on 346 bird-nights of observation). n p 12
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Free-ranging common nighthawks use torpor
Journal of Thermal Biology, 2004Co-Authors: Quinn E. Fletcher, Ryan J. Fisher, Craig K. R. Willis, R. Mark BrighamAbstract:Bouts of torpor are characterized by substantial reductions in body temperature and metabolic rate. Many birds in the order Caprimulgiformes use torpor; however, there is conflicting evidence whether or not Common Nighthawks (Chordeiles minor) have this ability. The purpose of our study was to examine whether free-ranging nighthawks enter torpor. Three out of eight birds that were monitored entered torpor on a total of four occasions. Our results suggest that torpor is not used as commonly as it is in other species of Caprimulgids providing incentive for further research to explain the ecological determinants of torpor use in Caprimulgids.
