Optimal Escape Theory

Optimal Escape Theory – Gambling with the Reaper 

Lizards have been prime subjects for ethological studies by scientists – reproduction cost, foraging mode, and predator-prey interaction are a few topics that have been investigated in the lizard world (Lizard Ecology 1994, 2007). I'd like to dive further into predator-prey interaction and discuss a paper by Ydenberg and Dill (1986) titled "The Economics of Fleeing From Predators". This literature is the backbone of my research methods.

The word "economics" in the title of this literature is extremely appropriate. Ydenberg and Dill outline the literal costs–benefit framework that prey attempt to balance to survive potential predatory advances. Bankruptcy is getting ran down by a lion, winning the lottery is successfully venturing to get to the watering hole, and back, alive. Ydenberg and Dill refute statements that claim detection of predators by prey immediately warrants a response, and that instead prey detect predators long before they make the decision to flee.

Ydenberg and Dill go into many examples of cost–benefit economics, using other taxa of wildlife along with a plethora of figures. Saving the audience of from minutiae, essentially, there is a cost the prey has to burden when it flees from predators. These burdens can be losses of foraging time, social interaction, and patrol of territory. So – Ydenberg and Dill argue that prey roll the dice, and make conscience bets against death itself delivered by the hands of a famished predator, because they if they weasel their way into staying around that area they've selected without dying (not being detected or captured), it's worth it!

Anolis lizards display this theory. Lizard locomotion is affected by temperature (Swoap et al., 1993). These lizards will flee sooner when approached at low temperatures, but they let predators get closer to them at higher temperatures because they're faster. This absolutely blows my mind that lizards do this. Anolis are more "bold" a higher temperatures, the bet against death is less risky. Now this changes even more when you throw in cover presence, cryptic morphology, and even the angle at which predators approach. My question for science: "Can we use this theory to own our advantage and increase detection of lizards in someway?".

 

Figure 1. Flight distance and temperature relationship in Anolis lizards (Ydenberg and Dill, 1986).

Literature Cited

Vitt L. J. and E. R. Pianka. Lizard Ecology: Historical and Experimental Perspectives. 1994. Princeton University Press.

Reilly S. M., L. B. McBrayer and D. B. Miles. Lizard Ecology. 2007. Cambridge University Press.

Swoap S. J., T. P. Johnson, R. K. Josephson and A. F. Bennett. Temperature, muscle power output and limitations on burst locomotor performance of the lizard dipsosaurus dorsalis. 1993. Journal of Experimental Biology. 174: 185–197

Ydenberg, R. C., and L. M. Dill. 1986. The economics of fleeing from predators. Advances in the Study of Behavior 16:229-249.