Shifts in morphology and diet of non-native sticklebacks introduced into Japanese crater lakes Tatsuya Adachi1, Asano Ishikawa2, Seiichi Mori3, Wataru Makino1, Manabu Kume3, Masakado Kawata1 & Jun Kitano1,2,4 1Division of Ecology and Evolutionary Biology, Graduate School of Life Sciencefs, Tohoku University, Sendai, Miyagi 980-8578, Japan 2Ecological Genetics Laboratory, National Institute of Genetics, Yata 1111, Mishima, Shizuoka 411-8540, Japan 3Biological Laboratory, Gifu-keizai University, Ogaki, Gifu 503-8550, Japan 4PRESTO, Japan Science and Technology Agency, Honcho Kawaguchi, Saitama 332-0012, Japan Keywords Abstract Adaptation, anthropogenic, caldera, contemporary evolution, fisheries, invasive, An increasing number of exotic animals are causing ecological problems. There- rapid evolution. fore, for better ecosystem management, it is important to understand how exotic Correspondence species colonize and adapt to novel environments. The threespine sticklebacks Jun Kitano, Ecological Genetics Laboratory, (Gasterosteus aculeatus) can be a good vertebrate model system to explore the eco- National Institute of Genetics, Yata 1111, logical and genetic mechanisms of adaptation not only in natural populations, but Mishima, Shizuoka 411-8540, Japan. Tel: also in non-native populations. Although morphological changes have been doc- 81-55-981-9415; Fax: 81-55-981-9416; umented in several introduced populations of stickleback, little is known about E-mail:
[email protected] the dietary changes during colonization into novel environments. Here, we investi- This research is supported by JST PRESTO gated the morphological and dietary changes of exotic threespine stickleback pop- program, Asahi Glass Foundation, Grant-in-Aid ulations introduced into three Japanese crater lakes (Lake Towada, Lake Kussharo, for Young Scientist (B) (22770075) and and Lake Shikotsu).