School of Forestry and Environmental Studies Yale University 370 Prospect Street, New Haven, CT 06511, USA.
R Soc Open Sci. 2015 Dec 2;2(12):150433. doi: 10.1098/rsos.150433. eCollection 2015 Dec.
In amphibians, abnormal metamorph sex ratios and sexual development have almost exclusively been considered in response to synthetic compounds like pesticides or pharmaceuticals. However, endocrine-active plant chemicals (i.e. phytoestrogens) are commonly found in agricultural and urban waterways hosting frog populations with deviant sexual development. Yet the effects of these compounds on amphibian development remain predominantly unexplored. Legumes, like clover, are common in agricultural fields and urban yards and exude phytoestrogen mixtures from their roots. These root exudates serve important ecological functions and may also be a source of phytoestrogens in waterways. I show that clover root exudate produces male-biased sex ratios and accelerates male metamorphosis relative to females in low and intermediate doses of root exudate. My results indicate that root exudates are a potential source of contaminants impacting vertebrate development and that humans may be cultivating sexual abnormalities in wildlife by actively managing certain plant species.
在两栖动物中，异常的变态性别比例和性发育几乎完全是由于合成化合物（如农药或药物）而引起的。然而，具有内分泌活性的植物化学物质（即植物雌激素）在农业和城市水道中很常见，这些水道中栖息着性发育异常的青蛙种群。然而，这些化合物对两栖动物发育的影响在很大程度上仍未得到探索。豆类，如三叶草，在农业领域和城市庭院中很常见，其根部会分泌植物雌激素混合物。这些根分泌物具有重要的生态功能，也可能是水道中植物雌激素的来源。我表明，三叶草根分泌物在低剂量和中剂量的根分泌物下，相对于雌性，会产生雄性偏斜的性别比例，并加速雄性变态。我的结果表明，根分泌物是影响脊椎动物发育的潜在污染物来源，人类可能通过积极管理某些植物物种来培育野生动物的性异常。
