On the Origin of Carnivory: Molecular Physiology and Evolution of Plants on an Animal Diet

Charles Darwin recognized that carnivorous plants thrive in nutrient-poor soil by capturing animals. Although the concept of botanical carnivory has been known for nearly 150 years, its molecular mechanisms and evolutionary origins have not been well understood until recently. In the last decade, technical advances have fueled the genome and transcriptome sequencings of active and passive hunters, leading to a better understanding of the traits associated with the carnivorous syndrome, from trap leaf development and prey digestion to nutrient absorption, exemplified, for example, by the Venus flytrap (Dionaea muscipula), pitcher plant (Cephalotus follicularis), and bladderwort (Utricularia gibba). The repurposing of defense-related genes is an important trend in the evolution of plant carnivory. In this review, using the Venus flytrap as a representative of the carnivorous plants, we summarize the molecular mechanisms underlying their ability to attract, trap, and digest prey and discuss the origins of plant carnivory in relation to their genomic evolution.