Mutualisms are important; we’re sure about that. Here’s something we don’t know as much about: are mutualisms resilient? As species go extinct or species appear in new places, as nutrient cycles change, and/or as the global climate changes, will the mutualisms that ecological systems rely on keep functioning?
Errbody knows that I like ant-plant mutualisms, including seed dispersal mutualisms where ants take seeds with juicy eliaosomes back to their nests, eat off the eliaosomes, and then dump the seeds. I also loooove snails and their close relatives: SLUGS. Today, we shall combine them, and see what happens to ant-plant dispersal mutualisms when invasive slugs get thrown into the mix. Below is the short version, and you can read all of the details in Meadley Dunphy et al. (2016).
Slugs eat elaiosomes, just like ants. But unlike ants, slugs eat the elaiosomes without moving the seeds, so the seeds aren’t dispersed. Furthermore, when slugs eat the elaiosomes off seeds, ants won’t disperse the seeds anymore, so the mutualism is disrupted. Moral of this story: Slugs. Ruin. Everything.
Meadley Dunphy, S.A., K.M. Prior, and M.E. Frederickson. 2016. An invasive slug exploits an ant‑seed dispersal mutualism. Oecologia 181:149–159.