Trinidadian guppies (Poecilia reticulata) are able to adapt to various environmental conditions and are even among the few species that can tolerate extensive pollution. In the Pitch Lake of Trinidad they live in highly toxic waters due to natural seepage of oil and bitumen. In this paper, we describe phenotypic divergence in several life-history traits between guppies from the Pitch Lake and from a nearby reference site with waters not polluted by bitumen/oil. We show that guppies from the Pitch Lake were (i) smaller and (ii) had a higher reproductive investment than those from the reference site. Furthermore, they (iii) produced more and smaller offspring. These results are congruent with a scenario of high mortality caused probably by a combination of water toxicity and higher predation than at the reference site. We therefore propose the Pitch Lake as an ideal system to study the effects of long-term (natural) water pollution on fishes, which might provide interesting insights into adaptation to extreme environments, and might further help to predict fish responses to anthropogenic pollution.

中文翻译：

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特立尼达的Pitch湖的孔雀鱼（Poecilia reticulata Peters，1869； Poeciliidae）的生活史

特立尼达孔雀鱼（Poecilia reticulata）能够适应各种环境条件，甚至是能够忍受广泛污染的少数物种。在特立尼达的沥青湖中，由于石油和沥青的自然渗透，它们生活在剧毒的水中。在本文中，我们描述了来自沥青湖和附近参考点的孔雀鱼在未受到沥青/油污染的水域中的几种生活史特征中的表型差异。我们显示，距参考湖的孔雀鱼孔雀鱼（i）较小，并且（ii）生殖投资较高。此外，他们（iii）产生了更多和较小的后代。这些结果与可能是由于水毒性和比基准地点更高的捕食相结合而导致的高死亡率的情景相吻合。