[In Depth] How the Venus flytrap acquired its taste for meat
Carnivorous plants have remarkable adaptations to catch and digest invertebrates. These aggressive feeding habits allow the plants to survive in poor soil by giving them a new source of nitrogen and other nutrients. Many biologists suspect ancestors of carnivorous plants evolved by adapting mechanisms normally used to detect and defend against herbivores. Now, this hypothesis has gained support from a detailed genetic study of Venus flytraps (Dionaea muscipula). Patterns of gene expression confirmed that the flytrap and a noncarnivorous plant use the same signaling pathway to detect insects. Experiments showed that the flytrap digests its prey with the same kind digestive enzymes that other plants use to ward off insects. A few hours after catching prey, the flytrap turns on another set of familiar genes to absorb nutrients; many of these genes are expressed in the roots of other plants. Author: Erik Stokstad