| ayu (plecoglossus altivelis) in a contact zone between amphidromous and landlocked forms: genetic analyses of populations in the yodo river system. | the migratory fish ayu, plecoglossus altivelis, has two forms: an amphidromous form found throughout the japanese islands and a landlocked form found in lake biwa. because lake biwa is one of the sources of the yodo river, which flows into osaka bay, it is likely that there has been contact between the two forms within the yodo river system. to examine the effects of such contact, 573 ayu were collected from the yodo river system and several other rivers and compared through an extensive investi ... | 2009 | 19719405 |