Motohide Seki (Faculty of Design / Assistant Professor)

Biological clocks in tropics

Many species from microbes, animals, and plants have biochemical systems that generate circadian rhythms. Those systems are largely classified into two groups, clock-type and hourglass-type; the former and the latter do and do not, respectively, generate rhythms under constant light exposure and/or constant darkness. Our theoretical model predicted that species distributed in temperate and tropical zones do and do not, respectively, require a clock-type system. Global-scale studies on microbes revealed that cyanobacterial species have evolutionarily altered their ancestral clock into an hourglass. Hypothesizing that some of tropical plants also have hourglasses, we are measuring rhythms of multiple tropical plant species.