Dry weight at eclosion, adult lifespan, lifetime fecundity, lipid and carbohydrate content at eclosion, and starvation and desiccation resistance at eclosion were assayed on a long-term laboratory population of Drosophila melanogaster, and one recently wild-caught population each of four other species of Drosophila, two from the melanogaster and two from the immigrans species group. The relationships among trait means across the five species did not conform to expectations based on correlations among these traits inferred from selection studies on D. melanogaster. In particular, the expected positive relationships between fecundity and size/lipid content, lipid content and starvation resistance, carbohydrate (glycogen) content and desiccation resistance, and the expected negative relationship between lifespan and fecundity were not observed. Most traits were strongly positively correlated between sexes across species, except for fractional lipid content and starvation resistance per microgram lipid. For most traits, there was evidence for significant sexual dimorphism but the degree of dimorphism did not vary across species except in the case of adult lifespan, starvation resistance per microgram lipid, and desiccation resistance per microgram carbohydrate. Overall, D. nasuta nasuta and D. sulfurigaster neonasuta (immigrans group) were heavier at eclosion than the melanogaster group species, and tended to have somewhat higher absolute lipid content and starvation resistance. Yet, these two immigrans group species were shorter-lived and had lower average daily fecundity than the melanogaster group species. The smallest species, D. malerkotliana (melanogaster group), had relatively high daily fecundity, intermediate lifespan and high fractional lipid content, especially in females. D. ananassae (melanogaster group) had the highest absolute and fractional carbohydrate content, but its desiccation resistance per microgram carbohydrate was the lowest among the five species. In terms of overall performance, the laboratory population of D. melanogaster was clearly superior, under laboratory conditions, to the other four species if adult lifespan, lifetime fecundity, average daily fecundity, and absolute starvation and desiccation resistance are considered. This finding is contrary to several recent reports of substantially higher adult lifespan and stress resistance in recently wild-caught flies, relative to flies maintained for a long time in discrete-generation laboratory cultures. Possible explanations for these apparent anomalies are discussed in the context of the differing selection pressures likely to be experienced by Drosophila populations in laboratory versus wild environments.
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机译：在长期实验的果蝇果蝇种群和一个最近被野生捕捞的另外四个物种中，测定了鸡粪的干重，成虫的寿命，寿命，卵泡中的脂质和碳水化合物含量以及鸡粪中的饥饿和抗干燥性。果蝇，其中两个来自黑腹果蝇，另外两个来自伊米兰属物种组。基于对黑腹果蝇选择研究推断的这些特征之间的相关性，这五个物种之间的特征均值之间的关系不符合预期。尤其是，未观察到生育力与大小/脂质含量，脂质含量和抗饥饿性，碳水化合物（糖原）含量和抗干燥性之间的预期正相关关系，以及寿命与生育力之间的预期负相关关系。除部分脂质含量和每微克脂质的抗饥饿性外，大多数性状在物种间的性别之间均呈强正相关。对于大多数性状，有证据表明存在明显的性二态性，但不同物种间的二态性程度没有变化，除了成年寿命，每微克脂类的抗饥饿性和每微克碳水化合物的抗干性外。总体上，D。nasuta nasuta和D. sulfigaster neonasuta（移居群）在羽化时比黑变种组物种重，并且倾向于具有更高的绝对脂质含量和抗饥饿性。然而，这两种移民群体的物种寿命比黑黑猩猩群体的物种短，平均每日繁殖力也较低。最小的物种D. malerkotliana（黑猩猩组）具有相对较高的每日繁殖力，中等的寿命和较高的脂质含量，尤其是在雌性中。 D. ananassae（黑腹果蝇组）的碳水化合物绝对含量和分数含量最高，但其每微克碳水化合物的耐干燥性在五个物种中最低。就总体性能而言，如果考虑到成年寿命，终生繁殖力，平均每日繁殖力以及绝对饥饿和抗干旱能力，在实验室条件下，D。melanogaster的实验室种群明显优于其他四个物种。这一发现与最近的几篇报道相反，相对于在离散世代实验室培养物中长期维持的果蝇而言，近来的野生果蝇具有更长的成年寿命和抗逆性。在实验室环境与野生环境下，果蝇种群可能会遇到不同的选择压力，讨论了这些明显异常的可能解释。
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