Biodiversity Research Center, Academia Sinica, Taipei, 11529, Taiwan;
Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, 905-0227, Japan.
Proc Natl Acad Sci U S A. 2021 Aug 24;118(34). doi: 10.1073/pnas.2101985118.
Synchronized mass coral spawning typically occurs several days after a full moon once a year. It is expected that spawning day is determined by corals sensing environmental change regulated by the lunar cycle (i.e., tide or moonlight); however, the exact regulatory mechanism remains unknown. Here, we demonstrate how moonlight influences the spawning process of coral, When corals in the field were shaded 1 and 3 d before the full moon or 1 d after the full moon, spawning always occurred 5 d after shading commenced. These results suggest moonlight suppresses spawning: a hypothesis supported by laboratory experiments in which we monitored the effects of experimental moonlight (night-light) on spawning day. Different night-light treatments in the laboratory showed that the presence of a dark period between day-light and night-light conditions eliminates the suppressive effect of night-light on spawning. In nature, moonrise gets progressively later during the course of the lunar cycle, shifting to after sunset following the day of the full moon. Our results indicate that this period of darkness between sunset and moonrise triggers synchronized mass spawning of in nature.
同步的大规模珊瑚产卵通常发生在满月后的几天，每年一次。人们预计产卵日是由珊瑚感应受月球周期（即潮汐或月光）调节的环境变化来决定的；然而，确切的调节机制仍然未知。在这里，我们展示了月光如何影响珊瑚的产卵过程。当野外的珊瑚在满月前 1 天和 3 天或满月后 1 天被遮蔽时，产卵总是在遮蔽开始后的第 5 天发生。这些结果表明月光抑制了产卵：这一假设得到了实验室实验的支持，我们在实验中监测了实验月光（夜间光）对产卵日的影响。实验室中的不同夜间光照处理表明，在白天光照和夜间光照条件之间存在黑暗期，消除了夜间光照对产卵的抑制作用。在自然界中，随着月球周期的进行，月出时间会逐渐推迟，在满月后的那一天之后，月出时间会移到日落之后。我们的结果表明，在日落和月出之间的这段黑暗时间触发了自然中珊瑚的同步大规模产卵。
