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Abstract：
Freshwater gammarids are known to colonise occasionally sinking-cave streams, providing contrasting morphological, life-history and ecophysiological adaptations compared to their surface conspecifics. In this study, a subterranean and a surface population of the species Gammarus balcanicus was surveyed for one year in a sinking-cave stream from the Western Carpathians (Romania). The results showed that the cave-dwelling population comprised individuals that were significantly larger compared to their surface conspecifics, had larger body-size at sexual maturity and that the females produced fewer, but larger eggs, compared to the population situated outside the cave. The trophic position and the omnivory were significantly higher for the cave-dwelling compared to surface population and the elemental imbalance for C:P molar ratios lower, but similar for C:N. However, the subterranean population did not present troglomorphic characters or longer lifespan as known for other cave-surface paired crustaceans. This, together with the rather extensive hydrological connection of the habitats, suggests active gene-flow between populations and similar response to seasonality for body-size distributions, indicating that the observed ecophysiological and life-history differences are rather the consequence of phenotypic plasticity than the result of genetic adaptation.
摘要：
已知淡水gammarids偶尔会在下沉的洞穴溪流中定居，提供对比的形态学，生活史和生态生理适应与其表面特性的比较。在这项研究中,在西部喀尔巴斯山脉（罗马尼亚）的下沉洞穴中，对Gammarusbalcanicus物种的地下和地表种群进行了为期一年的调查。结果表明，与地表物种相比，洞穴居民群体的个体明显更大，性成熟时体型较大，雌性产量较少，但鸡蛋更大,与洞穴外的人口相比。与地表种群相比，窑洞的营养位置和杂食性明显更高，而C：P摩尔比的元素失衡较低，但C：N类似然而,地下种群没有其他洞穴表面成对的甲壳类动物所熟知的象形特征或更长的寿命。这个,加上栖息地相当广泛的水文联系，表明种群之间活跃的基因流动和对体型分布的季节性相似的反应，表明观察到的生态生理和生活史差异是表型可塑性的结果，而不是遗传适应的结果。
