Adaptations of wild populations of the estuarine fish Fundulus heteroclitus to persistent environmental contaminants
Adaptations of wild populations of the estuarine fish Fundulus heteroclitus to persistent environmental contaminants
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DOI：
10.1007/s002270050520
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发表时间：
1999-06-01
期刊：
影响因子：
2.4
通讯作者：
Cooper, KR
中科院分区：
文献类型：
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作者：
Nacci, D;Coiro, L;Cooper, KR
许多水生物种，包括河口鱼Fundulus heteroclitus (mummichogs)，适应当地环境条件。我们进行了研究，以评估高度暴露的mummichos种群是否适应有毒的环境污染物。这些鱼类种群是被持久性和生物蓄积性污染物（类二恶英化合物或dlc）污染的城市河口的土著，这些污染物对鱼类的早期发育特别有毒。我们进行了实验室挑战实验，比较参考地点和这个高度污染地点[美国马萨诸塞州新贝德福德港（NBH）]的mummichog胚胎和幼虫对dlc的敏感性。虽然每组内的dlc反应性存在差异，但NBH鱼对dlc的敏感性远低于参考鱼。具体来说，与nbh收集的mummichog卵中测量的dlc浓度相似的dlc浓度对参考胚胎是致命的。此外，dlc反应性是遗传的，与母体污染物无关。这些发现与以下结论是一致的：NBH中的DLC污染有助于选择对这些环境污染物暴露的短期毒性影响具有抵抗力的鱼类。这种适应可能是鱼类种群在这个高度污染的地方持续生存的关键机制。对这一生态系统的进一步评估可能会提供有关这种“非自然”选择的直接和间接后果的重要信息。
Many aquatic species, including the estuarine fish Fundulus heteroclitus (mummichogs), adapt to local environmental conditions. We conducted studies to evaluate whether highly exposed populations of mummichogs adapt to toxic environmental contaminants. These fish populations are indigenous to an urban estuary contaminated with persistent and bioaccumulative contaminants (dioxin-like compounds, or DLCs) that are particularly toxic to the early development of fish. We conducted laboratory challenge experiments to compare mummichog embryos and larvae from reference sites and this highly contaminated site [New Bedford Harbor (NBH), Massachusetts, USA] for their sensitivity to DLCs. While there was variation in DLC-responsiveness within each group, fish from NBH were profoundly less sensitive to DLCs than reference fish. Specifically, concentrations of DLCs similar to those measured in NBH-collected mummichog eggs were lethal to reference embryos. Further, DLC-responsiveness was inherited and independent of maternal contaminant contributions. These findings are consistent with the conclusion that DLC contamination in NBH has contributed to the selection of fish that are resistant to the short-term toxic effects of these environmental-contaminant exposures. This adaptation may be a critical mechanism by which fish populations persist in this highly contaminated site. Further evaluation of this ecosystem may provide important information concerning the direct and indirect consequences of this "unnatural" selection.