Caffeine has the effect of activating dopamine, and it is known that we humans feel uplifted when we drink coffee.Even in insects, it has been reported that caffeine affects the sleep of flies and improves the learning and memory ability of bees.
In 2010, a group at the Graduate School of Life and Environmental Sciences, Okayama University discovered that when red flour beetle, a rice and wheat storage pest, was given caffeine, it quickly stopped pretending to be dead.We considered that the intake of caffeine affects the "movement" of insects, and this time, we investigated the effect of caffeine on the mating behavior established through "movement".
As a result, it was found that males of red flour beetle who drank caffeine took less time to court a female and mount it on a female than males who did not drink caffeine, and the copulator also protruded earlier. ..In other words, caffeine was found to have an energetic aspect that accelerates the pattern of red flour beetle courtship behavior.
On the other hand, in order to confirm sperm competitiveness, we used the mutant black mutant strain Kokunusutomodoki to mate a male who was given caffeine and a male who was not given caffeine with one female, and then either male. The results of investigating whether sperm were used for fertilization showed that male sperm fed with caffeine did not fertilize more eggs.That is, caffeine intake did not affect sperm egg fertility (sperm priority).
This is the first study in the world to discover that caffeine activates the sexual drive of male insects.It is not yet clear what function caffeine in cocoa and tea has in nature, and this result also suggests why plants have evolved to make caffeine. there is a possibility.
Paper information:[Ethology] Effects of caffeine on mating behavior and sperm precedence in Tribolium castaneum
