The plant signaling web reaches animals: plants that summon parasitic wasps as bodyguards, chemicals in insect spit that betray a feeding caterpillar, deer saliva that changes a tree's response, and mast years that flood a forest with seed to overwhelm predators. The episode notes that "the plant manipulates the animal" is shorthand for natural selection, not intent.
Who's who
- Ted Turlings+1 more episodeChemical ecologist; co-author of the 1990 wasp study and the volicitin paper
- James TumlinsonChemical ecologist behind the maize-parasitoid work and volicitin isolation
- Marcel Dicke+1 more episodeWageningen entomologist who pioneered the lima bean bodyguard system
- Hans AlbornChemical ecologist; lead author on the 1997 volicitin isolation
- W. Joe LewisUSDA entomologist; co-author of the 1990 Science paper
- Bettina OhseLead author of the 2017 roe-deer saliva study
- Diana TombackEcologist who documented the Clark's nutcracker-whitebark pine mutualism
Timeline
- 1980sDicke and colleagues show infested lima beans attract predatory mites
- 1990Turlings, Tumlinson and Lewis show damaged corn attracts parasitic wasps
- 1997Volicitin isolated from beet armyworm secretion triggers the wasp-attracting blend
- 2017Ohse et al. report simulated deer browsing changes defense chemistry in maple and beech saplings
- 2024A Nature Plants study links the summer solstice to continent-scale seed-year synchrony
Still debated
The deer-saliva result covers only two species, used simulated saliva, and lacks an identified molecule, so how general it is remains unproven. The proximate cues behind mast years and the net benefit of bodyguard recruitment in the wild are also unsettled.