Is it Good to be Eaten?

If you're trying to live a long and successful life as things in nature often are, getting eaten is possibly one of the last things on your mind. We might quite reasonably expect that being lunch is quite literally a dead end. And even if one is consumed partially, it's likely to be unhealthy and, depending on which body parts are missing, reproduction would be out of the question. But not all of nature's creatures are hell bent on trying to escape the metaphorical dinner table. Can being eaten then be a good thing?

Having something take a nibble out of you might not be as bad as it may seem if you were a plant. Unable to run and unable to hide, plants have developed some unconventional defences to keep them going in case of an attack; one of these being tolerance. Tolerant plants shrug off herbivory with a disinterested “Whatever” as they are simply able to regrow lost parts and don't suffer any ill effects for it. A neat trick, but you can take it a step further. The Scarlet Gilia is an example of a plant that has done just that. These plants overcompensate for damage dealt by a herbivore and end up with more flowers and fruits than plants that hadn't been damaged. As a result, whereas most plants are expected to do everything in their disposal to keep herbivores away, the Scarlet Gilia might be more likely to be caught holding up a “All you can eat buffet” sign.

Being eaten might be useful for plants without a superpowered healing factor as well, though in more subtle ways. Plants are often in a difficult relationship with the animals that pollinate them. To get pollinators to visit, the plant needs to present some sort of reward, and the pollina-tors often claim the pollen itself, or other plant parts as that reward. This is perhaps most apparent in the case of the fig plants. The fig can't reproduce without its sole pollinators, the aptly named fig wasps, but the wasps only seek out figs to lay eggs in them. Eggs that hatch into voracious larvae that eat the figs' flowers inside out. Loss of body parts today for children tomorrow is a trade that the fig is willing to take (to an extent). Which just goes to show how far some creatures are willing to go for sex. 

Plants have even evolved appendages that exist for the sole purpose of being eaten. Such is the case with fruits. Fruits hold seeds, and for a variety of reasons that are beyond the scope of this article, it's a good idea for seeds to plant themselves some way away from their parents. There is but one snag: seeds can't walk. Fruits solve this problem by strategically being eaten by something more mobile, most commonly birds and small mammals. Fruits turn up in their highest numbers in synchrony often when fruit eaters are also at peak presence, they present bright colours to catch the eye, and if they could speak the forests would certainly be filled with the cries of “Eat me!” The seeds themselves are indigestible and therefore complete the journey from one end of the gastrointestinal tract to the other relatively unscathed. They are then deposited some distance away and that too in a handy patch of fertiliser. Ingenious.

So if you ever find yourself about to be served for lunch, ask yourself one question: “Am I a Scarlet Gilia, a fig or a fruit?” If you answer yes to one of those, then don't worry, you'll be okay.

References: 
Bronstein JL, Alarcon R, Geber M. New Phytologist172 (2006)

Herre EA, Jander KC, Machado CA. Annu. Rev. Ecol. Evol. Syst.29 (2008)

Herre CM in Plant-Animal Interactions:An Evolutionary Approach, Herre CM, Pellmyr O (Blackwell Publishing, Australia, 1st Edition,  2002) Chapter 7

Paige KN. Ecology 73 (1992)

Aadiyat is an aspiring biologist and is consequently terrified of social interaction in every form. Please don't contact him at aadiyat.ahmad@gmail.com