Conversation

AAAS: "Odd, fingerlike appendage helps this orchid reproduce." Understanding plant reproductive strategies is vital for conserving endangered species.The intricate pollination strategies within Orchidaceae have fascinated naturalists for over a century (Darwin, 1862). Life can get lonely for orchids in the genus Stigmatodactylus, as they grow in dark + secluded places where it's easy to be missed by pollinators. Stigmatodactylus is a set of flowering plants from the orchid family, Orchidaceae, with thirteen currently recognized species, native to China, Taiwan, Japan, the Himalayas, the Philippines, Malaysia, Indonesia, New Guinea and the Solomon Islands. "But one group has evolved a poppy seed–size “finger” that makes sure pollination continues, even if bugs don’t show up, a researcher reports today in Plants, People, Planet." The name combines Greek for finger and stigma, a reference to the fact that the plants in this group have a tiny, white, fingerlike projection hanging down from their stigma, the female part of the flower [marked by the red arrow]. "The reproductive biology of S. sikokianus was investigated through pollination observations, artificial pollination experiments, and detailed studies of column morphology." The trick discovered is that after 3 days without insect visits, the flowers of S. sikokianus wilt slightly, enabling the finger to hinge upward to reach pollen sacs above the stigma, thus allowing the plant to fertilize itself. Clearly any wallflower would get tired of waiting to be asked to dance after being patient for 3 whole days.