Molecular systematics demonstrate that carnivorous plants have evolved at least ten times independently, in five orders, 12 families, and 19 genera of angiosperms. Carnivory has arisen once in Nepenthales (a segregate of Caryophyllales), once in Oxalidales, twice in Ericales, and three times each in Lamiales and Poales. Estimated crown ages of these ten lineages range from 1.9 to 81 million years (Mya), with the youngest three lineages (1.9 – 2.6 Mya) being all single genera of Poales, and all involving one or two carnivorous species in an otherwise noncarnivorous group. We now understand the evolution of carnivorous plants based on knowing when and (often) where they diverged from specific noncarnivorous ancestors; inferring which traits were gained, which were retained, and which of the latter may have been crucial preadaptations for carnivory; and identifying the evolutionary drivers of carnivory by evaluating the ecological differences between carnivorous plants and their noncarnivorous relatives.
Molecular Systematics of the Order Crocodilia
