Study Confirms Darwin's 150-Year-Old Carnivorous Plant Theory

On August 4, a study published in Nature Communications has validated a hypothesis proposed by Charles Darwin 150 years ago, indicating that certain Saxifraga species exhibit carnivorous behavior. The investigation, spearheaded by botanists Doug Soltis from the University of Florida and Hang Sun from the Kunming Institute of Botany, focused on Saxifraga candelabrum, which thrives in the high-altitude Hengduan Mountains. The researchers observed that mature specimens had an average of 71 insects on their inflorescence branches, while younger plants had few or none, hinting at a link between branch density and insect capture. The study revealed that these plants attract insects through scent and selectively trap smaller insects, avoiding larger pollinators. Chemical analyses identified phosphatase, an enzyme typical of carnivorous plants, and nitrogen isotope labeling confirmed nutrient absorption from fruit flies. Genetic studies indicated shared genes with other carnivorous plants. Soltis suggests that carnivory might be more prevalent among plants than previously recognized, and he speculates that other Saxifraga species with sticky hairs could also be carnivorous. Botanist Susan Myers from the Pittsburgh Botanic Garden, who was not part of the research, noted that this study underscores the vast unknowns in plant biology. These findings not only affirm Darwin's predictions but also pave the way for further botanical exploration.