Some like it hot: factors impacting thermal preferences of two Ponto-Caspian amphipods Dikerogammarus villosus (Sovinsky, 1894) and Dikerogammarus haemobaphes (Eichwald, 1841).

摘要: Temperature is a crucial factor determining biology and ecology of poikilothermic animals. It often constitutes an important barrier for invasive species originating from different climate zones but, on the other hand, may facilitate invasion process animals with wide thermal preferences high resistance to extreme temperatures. In our experimental study, we investigated behaviour two Ponto-Caspian amphipod crustaceans-Dikerogammarus villosus Dikerogammarus haemobaphes. Both are known live under range conditions which promote their invasion. Moreover, both these amphipods hosts microsporidian parasites co-evolved them within region spread in European waters. As presence parasite influence its host, expected observe behavioural changes infected individuals studied leading (1) fever (selecting warmer habitat) or (2) anapyrexia colder habitat). The experiment (N = 20) was carried out 30 min 100 cm. 20 cm boths sides were not avaliable long gradient (0-40 °C), using randomly selected adult one species. At end each trial, checked position along determined sex infection status (uninfected by microsporidium species). D. villosus Cucumispora dikerogammari whereas D. haemobaphes host C. dikerogammari, Dictyocoela muelleri D. berillonum. Thermal depended sex. Females preferred microhabitats (often much above 30 °C) than conspecific males females D. haemobaphes, no significant differences found among sexes D. haemobaphes. stayed water more uninfected this species, selecting temperatures higher 30 °C, be explained either as constituting defence mechanism against infection, manipulation increasing fitness. On none affected including also changing D. villosus. Our research presents complexity evidence that microsporidia trigger change temperature preferendum those observations result host-parasite coevolution time vary (Poulin, 2010).