Nancy Schoeppner & the Ecology of Awesomeness
I sure don't know Nancy Schoeppner at all. She really flies under the internet radar, this is literally the only actual information I could find on her. I only paper-know her, as in I've read a handful of what I'm guessing is her PhD research with Rick Relyea at the University of Pittsburgh. But, in addition to being an EXCELLENT science communicator (I totally heart reading her papers!) and experimental biologist, her work has really shaped some of my, hitherto undescribed, thinking about how prey decide whether or not to be terrified. There are various names for this sub-discipline of Ecology: Risk-Assessment, Inducible Defenses, the Ecology of Fear (Mwahhahahahaha! ...).
The quick and dirty is this: Hark back unto my first blog post where I described the terror of being an oyster and knowing a predatory snail was coming for you, grinding a hole into your shell, hell-bent on suckingyourgutsout! In that moment, that oyster can't really do anything about the snail, except hope he gets distracted by a pretty lady snail on an adjacent oyster and forgets about his hunger on his libidinous quest to pass his genes on (somewhat like terrestrial snails). But some organisms can tell when they're in danger and do something about it - even plants, I kid you not! Certain organisms can grow helmets and put spikes on their necks to make it harder for predators to eat them (so goth!), they can try to grow faster so that they get too big to be eaten by predators, or, well, they can run away and hide. These are called inducible defenses. Trying to figure out how these guys tell when they're in danger is, it turns out, really fun [for Emily].
Nancy's work has tested a bunch of hypotheses about risk assessment, and I think they are applicable to human decision-making in times of potential threat by carnivorous preadators (i.e., zombies, flesh-eating bacteria, Orca: the Killer Whale, etc.). So here are Nancy Schoeppner's:
3 Risk-Assessment Rules to Live and Die By
1. If you can smell your family being eaten, there's a pretty good chance you also are in danger of being eaten, and you should do something about it.
If you can smell your friends being eaten, there's still a good chance you're in danger, but maybe don't freak out so much. If all you can smell is some folks you don't even really know and have never met and who have a totally different diet and culture from you getting eaten - no biggie! It's not really your problem, becuase those other prey (suckers!) are so unlike you, the predator probably doesn't even recognize you as potential food! (NB: It's possible that this rule also guides US cultural attitudes and policy decisions.)
2. If there is a large cost to defending yourself, you should def. wait until you have good information that there is a serious, serious risk.
Tadpoles in Schoeppner's experiments only changed their growth patterns (very pricey, energetically, and also non-reversible, so they're screwed with their permanent giant tails if they're wrong!) when they smelled predators consuming AND digesting friends/family, but they changed their behavior (who cares?! You can just come out from your hiding space when you realize your friends were punking you, and all you lose is your dignity!) in response to less threatening smells.
3. Do the math, dummy.
If there's only one shark in the water (Fig. 1) but 500 tasty fat people, simmer down! Probably that shark will rip off somebody else's leg (phew!) and then realize humans taste like diet soda and a bitterness that can only be acquired from a lifetime of regrets. If the shark attacks randomly, the probability you will lose your leg is 1 in 500. But if you all panic, you miss valuable wave time, and increase the probability that you will get crushed by the 499 panicking morons on their way to shore. If, however, there are 499 sharks, and 500 people, the probability that you will leave the beach with all 4 limbs is 1 in 500, and so taking the chance of getting stampeded by your fellow prey is probably still a safe bet.
Fig. 1. Do not run from this shark - it probably won't rip your
leg off because, no offense meant, but it would probably rather
eat a brownie sundae. I put this picture in here because this post
is long and boring.
There are most certainly more rules, but these are the best supported. I hope to add my own rules some day. For instance, if you're on vacation, how can you tell whether that Italian man is ogling you because he's hungry, or because he likes the cut of your minigonna? Are there threat-signals that transcend international boundaries?
My point is that plants and animals seem to be very good at telling when they are safe and when they should hit the deck, and can optimize these situations to make sure that they will live long enough to make many, many babies. Even cooler, they do this all without actuarial tables, the Central Intelligence Agency, night-vision goggles (well some of them do have pretty good night vision), or even very sophistocated sensory systems. I have really benefited from Nancy's clear thinking and writing, and her thorough experimental technique - Swoon. I'd love to write a review paper with her some day - but these are merely the silly daydreams of a graduate student putting off other work...
Nancy Schoeppner - Selected Publications (in no detectable order):
1. Schoeppner & Relyea (2008) Oecologia. Detecting small environmental differences: risk-response curves for predator-induced behavior and morphology. 154:743-754.
2. Schoeppner & Relyea (2009) Functional Ecology. Interpreting the smells of predation: how alarm cues and kairomones induce different prey defences. 23: 1114-1121.
3. Schoeppner & Relyea (2009) Copeia. When Should Prey Respond to Consumed Heterospecifics? Testing Hypotheses of Perceived Risk. 1: 190-194
4. Schoeppner & Relyea (2005) Ecology Letters. Damage, digestion, and defence: the roles of alarm cues and kairomones for inducing prey defences. 8:505-512.
- Emily Grason