Department of Bioscience, Integrative Ecology and Evolution, Aarhus University, Ny Munkegade 114-116, DK-8000 Aarhus C, Denmark.
Exp Gerontol. 2013 Nov;48(11):1189-95. doi: 10.1016/j.exger.2013.07.012. Epub 2013 Aug 2.
Drosophila melanogaster is frequently used in ageing studies to elucidate which mechanisms determine the onset and progress of senescence. Lines selected for increased longevity have often been shown to perform as well as or superior to control lines in life history, stress resistance and behavioural traits when tested in the laboratory. Functional senescence in longevity selected lines has also been shown to occur at a slower rate. However, it is known that performance in a controlled laboratory setting is not necessarily representative of performance in nature. In this study the effect of ageing, environmental temperature and longevity selection on performance in the field was tested. Flies from longevity selected and control lines of different ages (2, 5, 10 and 15 days) were released in an environment free of natural food sources. Control flies were tested at low, intermediate and high temperatures, while longevity selected flies were tested at the intermediate temperature only. The ability of flies to locate and reach a food source was tested. Flies of intermediate age were generally better at locating resources than both younger and older flies, where hot and cold environments accelerate the senescent decline in performance. Control lines were better able to locate a resource compared to longevity selected lines of the same age, suggesting that longevity comes at a cost in early life field fitness, supporting the antagonistic pleiotropy theory of ageing.
黑腹果蝇常被用于衰老研究中，以阐明哪些机制决定了衰老的发生和进展。在实验室中进行测试时，选择延长寿命的品系通常在生活史、应激抗性和行为特征方面表现得与对照品系一样好或更好。在选择延长寿命的品系中，功能性衰老的发生速度也较慢。然而，众所周知，在受控的实验室环境中的表现不一定能代表在自然界中的表现。在这项研究中，研究了衰老、环境温度和寿命选择对野外表现的影响。来自不同年龄（2、5、10 和 15 天）的寿命选择和对照品系的果蝇在没有天然食物来源的环境中释放。对照果蝇在低温、中温和高温下进行测试，而选择延长寿命的果蝇仅在中温下进行测试。测试了果蝇找到并到达食物源的能力。中等年龄的果蝇通常比年轻和年长的果蝇更善于找到资源，而炎热和寒冷的环境会加速性能的衰老下降。与同龄的选择延长寿命的品系相比，对照品系更能找到资源，这表明长寿是以早期生活野外适应能力为代价的，这支持了衰老的拮抗多效性理论。
