It turns out that sea urchins use light to regulate digestion. Japanese scientists from the University of Tsukuba conducted a study of sea urchins and found how light affects their digestion. Experts grew echinoderm larvae and placed them in a PCR plate, which was periodically fed light. The experiment took place first without the food, algae, and then with them.
As a result, the study showed that the animals use light to regulate the opening and closing of the gatekeeper of the stomach. It plays an important role in the digestive system. The number of larvae that responded to light approximately doubled in the presence of food.
Since many living organisms use light as the most important biological signal. Experts suggested that nerve cells may have originally evolved to regulate digestion using light, for example, to guide the time of day.
The authors of the study are confident that the results of experiments will help in the future to better understand the evolution of light-dependent systems. They also plan to continue their work and find out how these systems have changed in other animals.