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Foragers of the stingless bees genus Melipona may produce intranidal sounds that are correlated with food location and quality. In this study, we provide the first detailed
analysis of pulsed sounds produced by Melipona panamica foragers while feeding on a carbohydrate food source. We trained foragers to a 2.5-M sucrose feeder under normal, ambient
temperature (23–33°C) and lower temperature (11–25°C) conditions. We recorded forager sounds under both conditions and tested
the effect of temperature of the thorax, feeder plate, and air on sound temporal characteristics. Forager energetic expenditure
and the number of pulses per visit were significantly higher in the cold condition than in the normal condition. Foragers
spent a longer time at the feeder under the cold condition than during the normal condition. Interpulse durations were significantly
shorter in the cold condition than in the normal condition and became progressively and significantly shorter at the end of
each performance. Thus, pulse production increased before departure. Foragers increased their thoracic temperatures above
ambient at all experimental air temperatures. Under chilled conditions, foragers had a significantly greater difference between
thorax temperature and ambient air temperature than under normal conditions. Foragers must achieve a minimum flight muscle
temperature before take-off, and thus forager sounds may be linked to muscle warm-up. 相似文献
53.
Adenosine triphosphate (ATP) content and carbon dioxide (CO2) production in soil vary considerably, depending on soil type, water content, light, stirring of soil, storage conditions, date of sampling, and chemicals added. In most soils, the biomass calculated on the basis of ATP-content was in line with that calculated on the basis of CO2-production. 相似文献
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Sources of metals in New York City wastewater 总被引:1,自引:0,他引:1
L A Klein M Lang N Nash S L Kirschner 《Journal - Water Pollution Control Federation》1974,46(12):2653-2662
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