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Green woodhoopoes phoeniculus purpureus and obligate cavity roosting provide a test of the thermoregulatory insufficiency hypothesis


, : Green woodhoopoes phoeniculus purpureus and obligate cavity roosting provide a test of the thermoregulatory insufficiency hypothesis. Auk 108(2): 285-293

In Kenya, Green Woodhoopoes (Phoeniculus purpureus) seem constrained to sleep in aboreal cavities in spite of a high risk of capture within these chambers by nocturnal predators. Ligon et al. (1988) proposed that because woodhoopoes are incapable of adequate shivering thermogenesis at low nocturnal ambient temperatures, they are forced to roost in insulated tree cavities to maintain their body temperatures. We tested the thermoregulatory insufficiency hypothesis on 10 wild-caught woodhoopoes. From measurements of oxgyen consumption (.ovrhdot.VO2) at ambient temperatures from -10.degree. C to + 40.degree. C, we find no support for the hypothesis. Below thermoneutrality, .ovrhdot.VO2 increased linearly as ambient temperature (Ta) decreased. The equation, .ovrhdot.VO2 (ml O2 .cntdot. h-1) = 525.5 - 5.53 (Ta), described the relationship for males, and .ovrhdot.VO2 (ml O2 .cntdot. h-1) = 252.8 - 5.65 (Ta) for females. Body temperature (Tb) for the sexes did not differ (mean = 39.3.degree. C). Birds that were in good body condition maintained their Tb even at -10.degree. C for several hours. Within the thermal neutral zone, .ovrhdot.VO2 averaged 124.6 ml O2 .cntdot. h-1 for males and 115.9 ml O2 .cntdot. h-1 for females. Body mass averaged 79.70 g for males and 72.19 g for females. Total evaporative water loss of Green Woodhoopoea showed no relationship to Ta below 25.degree. C. Evaporative water loss averaged 179.6 mg H2O .cntdot. h-1 in males and 170.9 mg H2O .cntdot. h-1 in females. Above 25.degree. C, water loss increased exponentially with temperature. At 40.degree. C, woodhoopoes dissipated 55.8% of their metabolic heat production through water evaporation from respiratory passage and skin. Dry thermal conductance (.ovrhdot.Hd) between 0 and 30.degree. C averaged 31.7 mW .cntdot. .degree. C-1 for males and 32.5 mW .cntdot.degree. C for females. Above 30.degree. C, .ovrhdot.Hd rapidly escalated, reaching nearly 80 mW .cntdot.degree. C-1 at the highest temperatures.

US$19.90

DOI: 10.2307/4087953


Other references

Mandrand M A.; W.L.F.; Boxer D., 1990: Hydrogenase mutants of escherichia coli defective in nickel uptake. Belaich, J -P , M Bruschi And J -L Garcia (Ed ) Fems (Federation Of European Microbiological Societies) Symposium, No 54 Microbiology And Biochemistry Of Strict Anaerobes Involved in Interspecies Hydrogen Transfer; Meeting, Marseille, France, September 12-14, 1989 Xii+543p Plenum Press: New York, New York, Usa; London, England, Uk Illus 337-348

Steinberg, M.S.; Duguay, D., 2000: Are cadherins really homophilic? Eight different cadherins cross-adhere strongly. Cell Biology International 24(12): 973

Zhi, Y.; Yang, J.; Tian, S.; Yuan, F.; Liu, Y.; Zhang, Y.; Sun, P.; Song, B.; Chen, Z., 2012: Quantitative structure-activity relationship studies on indenoisoquinoline topoisomerase I inhibitors as anticancer agents in human renal cell carcinoma cell line SN12C. Topoisomerase I is important for DNA replication and cell division, making it an attractive drug target for anticancer therapy. A series of indenoisoquinolines displaying potent Top1 inhibitory activity in human renal cell carcinoma cell line SN12...

Yoon, Y.; Stopforth, J.D.; Kendall, P.A.; Sofos, J.N., 2004: Inactivation of Salmonella during drying and storage of Roma tomatoes exposed to predrying treatments including peeling, blanching, and dipping in organic acid solutions. The objective of this study was to evaluate the influence of predrying treatments, i.e., peeling, blanching prior to inoculation, and dipping in organic acid solutions, on inactivation of Salmonella during drying (60 degrees C for 14 h) and aerobi...

Anderson Brian G.; Droser Mary L.; Bottjer David J., 1994: Variation in the distribution of two-component Ophiomorpha-dominated ichnofabrics within sequences and systems tracts. Abstracts with Programs - Geological Society of America 26(7): 431

Wilbourn, A.J., 1991: Thoracic outlet syndromes: a plea for conservatism. This article focuses on the controversial subtype of TOS, which presents primarily sensory sentence, normal neurologic examination, normal electrodiagnostic study results, and normal neck x-ray films. At present, this entity is so variable in its...

Wagner, A.H.; Hildebrandt, A.; Baumgarten, S.; Jungmann, A.; Müller, O.J.; Sharov, V.S.; Schöneich, C.; Hecker, M., 2011: Tyrosine nitration limits stretch-induced CD40 expression and disconnects CD40 signaling in human endothelial cells. Hemodynamic forces are important effectors of endothelial cell phenotype and function. Because CD40-CD154 interactions between endothelial cells and mononuclear leukocytes or activated platelets play an important role in vascular dysfunction, we i...

Kountouras, J.; Boura, P.; Apostolides, G.; Zaharioudaki, E.; Tsapas, G., 1994: In vivo effect of omeprazole on HLA-DR expression and the monocyte-macrophage function in patients with duodenal ulcer disease. It is not known if omeprazole possesses any action on immune system. Therefore, we examined the effect of omeprazole on parameters of cellular immunity [T-cell subsets-CD3+, CD4+, CD(8+)- and HLA-DR expression on peripheral blood lymphocytes (PBLs...

Morgan, W.P.; Harding, K.G.; Hughes, L.E., 1983: A comparison of skin grafting and healing by granulation, following axillary excision for hidradenitis suppurativa. The treatment of established hidradenitis suppurativa demands complete excision of the apocrine glands in the affected area. Ten patients undergoing bilateral excision of the axillary skin, had one axilla grafted and the other allowed to heal by g...

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