Parasites are the ultimate moochers, earning a living by stealing hard-earned nutrients from their hosts. Now, a new study in plants suggests that parasites sometimes give something back: foreign genes.
Gene swapping between species, a process known as horizontal gene transfer, is relatively common and well studied in bacteria. However, scientists have only recently found evidence of horizontal gene transfer in plants. Last summer, two groups of researchers—one led by Jeffrey Palmer of Indiana University in Bloomington and the other by Charles Davis of the University of Michigan in Ann Arbor—reported independently that some host plants pass their genes to the parasitic plant species that feed off them.