Ecology Ch. 9 Flashcards
Optimal foraging theory
Evolutionary theories of behavior based on the assumption that the foraging behaviors of individuals are optimal by maximizing the rate of energy gained per unit time
Energy maximizer
An individual that maximizes the rate of energy gained per unit time by choosing prey or patches with the highest net energy gain (Eg-Eh)
Time minimizer
An individual that maximizes the rate of energy gained per unit time by choosing prey or patches with the lowest time required (Ts+Th)
Optimal diet theorem
A rate-maximizing forager will include less profitable prey items into their diet until the sum of rate of energy gain no longer increases from the addition of the next most profitable prey type
Marginal value theorem
A rate-maximizing forager will choose the residence time for each patch type so that the marginal rate of gain at the time of leaving equals the long term average rate of energy intake in the habitat
Give-up density
Density of prey in a patch at the time of leaving as predicted by the marginal value theorem
Red Queen hypothesis
An evolutionary hypothesis which proposes that organisms must constantly adapt to survive while pitted against ever-evolving opposing organisms in an ever-changing environment
Evolutionary Arm Race
Predators and prey co-evolve adaptations for prey capture and predator avoidance due to their strong evolutionary influence on one another
Search image
As foragers (or predators) encounter potential food items (or prey), they develop an enhanced ability to recognize those items in the future when they are foraging (or hunting)
Dilution effect
Safety in numbers that comes from swamping the ability of local predators to consume prey
Many eyes hypothesis
Safety in numbers that comes from an increased probability of detecting a predator’s approach by a group of vigilant prey
