Evolutionary ecology of guppies (Poecilia reticulata) in oil-polluted waters in Trinidad

淡水生态系统受到生物多样性危机的严重影响，根据世界自然保护联盟的数据，三分之一的淡水物种面临灭绝的风险。造成这一损失的主要原因之一是污染，因为工农业的径流在淡水汇中积累，导致死亡率高、人口减少和物种丰富度下降。原油就是这样一种污染物，它造成受影响生物体的畸形生长、免疫反应和繁殖力下降，并具有致癌性。尽管如此，一些物种似乎能够适应这些条件，包括活产鱼，孔雀鱼（Poecillia reticulata）。在特立尼达岛，孔雀鱼已经独立地在许多被原油污染的水道中殖民和建立种群，包括沥青湖，这是一个由石油和沥青自然上升形成的沥青湖。这为研究一个物种如何能够科普或适应原油污染造成的极端环境提供了一个独特的研究系统。本研究旨在全面了解这些耐油种群的进化生态学。这将通过调查它们的种群遗传学，饮食和肠道微生物组，以及种内竞争和与捕食者相互作用的模式来实现。

Freshwater ecosystems are disproportionately impacted by the biodiversity crisis, with one in three freshwater species at risk of extinction according to the IUCN. One of the main drivers of this loss is pollution, as run-off from industry and agriculture accumulates in freshwater sinks leading to high mortality levels, reduced population size and species richness. Crude oil is one such pollutant, causing deformed growth, reduced immune response and fecundity in affected organisms, as well as being carcinogenic. Despite this, some species appear able to adapt to these conditions, including the livebearing fish, the guppy (Poecillia reticulata). In Trinidad , guppies have independently colonised and established populations in numerous waterways polluted with crude oil, including the Pitch Lake, an asphalt lake formed from natural upwelling of oil and bitumen. This provides a unique study system for investigating how a species may be able to cope with or adapt to the extreme environment caused by crude oil pollution. This study aims to develop a comprehensive understanding of the evolutionary ecology of these oil-tolerant populations. This will be achieved through investigations into their population genetics, their diet and gut microbiome, but also into patterns of intraspecific competition and interactions with predators.