Most gymnosperms are wind-pollinated, but some are insect-pollinated, andinEphedra(Gnetales), both wind pollination and insect pollination occur.Little is, however, known about mechanisms and evolution of pollinationsyndromes in gymnosperms. Based on four seasons of field studies, weshow an unexpected correlation between pollination and the phases of themoon in one of our studied species,Ephedra foeminea. It is pollinated by dip-terans and lepidopterans, most of them nocturnal, and its pollinationcoincides with the full moon of July. This may be adaptive in two ways.Many nocturnal insects navigate using the moon. Further, the spectacularreflection of the full-moonlight in the pollination drops is the only apparentmeans of nocturnal attraction of insects in these plants. In the sympatric butwind-pollinatedEphedra distachya, pollination is not correlated to the fullmoon but occurs at approximately the same dates every year. The lunar cor-relation has probably been lost in most species ofEphedrasubsequent anevolutionary shift to wind pollination in the clade. When the services ofinsects are no longer needed for successful pollination, the adaptive valueof correlating pollination with the full moon is lost, and conceivably also the trait.
