Ed Yong reports on research by Jianqiang Wu of the Chinese Academy of Sciences into one of my favorite creepy plants: dodder (Cuscuta sp.). Wu’s work indicates that distinct plants parasitized by a connecting dodder vine can use it to exchange chemical signals, say, in response to herbivory.
It’s not that dodder has evolved to do this. The parasite is a generalist with unfussy taste in hosts, so it doesn’t really benefit by improving the lives of the plants it attacks. And Wu still suspects that the transmission mechanism does more harm than good, by sapping its hosts of water and nutrients. But it’s perhaps surprising that it does any good at all.