Ethological dynamics in diorama environments

Temperature is one of the critical environmental factors for living organisms, whose survival is difficult either at inappropriately low or high temperature. Microorganisms detect thermal environment by thermosensor and steer the swimming direction skillfully toward the temperature suitable for survival. This behavior of accumulation to optimal temperature is termed thermotaxis. In this study, we aim to identify the thermosensor responsible for thermotaxis in microalgae and to reveal how the motility is regulated by the information from the thermosensor, resulting in accumulation to optimal temperature. The degree and direction of thermotaxis are affected greatly but precisely by physiological conditions such as cell’s metabolic state and environmental factors such as light and chemicals. This study elucidates how the view of thermal environment seen by microalgae change with physiological conditions and environmental information.