Ecophysiological investigation of the environmental adaptation of Korean mudskippers

通过3年的项目，澄清了以下几点1.对采自日本、韩国和中国的大弹涂鱼的线粒体DNA分析表明，通过地理隔离，日本种群已与亚洲大陆的种群隔离。大多数日本物种被认为是在大约15,000年前从亚洲大陆的母种群中分离出来的，然而，据估计，分离的时间要早得多，在240,000-2,650,000年前。对韩国沿海几个地点的内分泌干扰物质的测量表明，来自人口稠密和工业化地区的污水中含有女性荷尔蒙样活动的化学物质严重污染了世外湖和邻近地点。对越冬期前不久在育州河口采集的弹涂鱼的身体成分分析显示，肝脏重量和体脂含量比观察到的日本个体高2.5倍。据估计，韩国南部海岸的冬眠期比日本长2个月，韩国鱼的高脂肪含量是对冬眠期间身体能量储存的一种适应，以降低死亡率。

The following points have been clarified through the 3 year project.1. Analysis of mitochondrial DNA of the mudskipper Boleophthalmus pectinirostris collected in Japan, Korea and China demonstrated that the Japanese population had been isolated from the populations of the Asian continent through geological isolation. Most of the Japanese species have been considered to have isolated from the mother populations in the Asian continent approximately 15,000 years ago, however, the isolation of the mudskipper is estimated to have occurred in much earlier time, 240,000-2,650,000 years ago.2. Measurements of endocrine disrupting substances in several locations along Korean coast indicated that lake Shiwa and adjacent locations are heavily contaminated by chemicals that exert female-hormone-like actions contained in sewage water from highly populated and industrialized areas.3. Body composition analysis of the mudskippers collected in Yoesu estuaries shortly before hibernation period demonstrated liver weight and body fat content, which are 2.5 times higher than those observed for Japanese individuals. Hibernation period in Korean south coasts is estimated to be 2 months longer than in Japan, and the high fat content of the Korean fish is an adaptation for the storage of body energy to reduce morality during hibernation periods.