Exam 6: Avoiding Predators and Finding Food

A seed-eating bird forages in groups with competitive companions. A behavioral biologist who is formulating a hypothesis is likely to consider this an example of

Smaller seed-eating birds select smaller seeds than larger seed-eating birds do. A behavioral biologist who is formulating a hypothesis is likely to consider this an example of

Refer to the figure. The figure shows a matrix of fitness payoffs for interactions between two behaviorally different types of gulls: those that always fish for themselves and those that sometimes steal fish from others. P stands for the baseline fitness that a gull derives when it fishes for itself. B is the fitness gained by a thief when it steals a fish from a fish-for-self type. C is the fitness cost associated with an attempt to steal a prey. What is the significance of the fact that in a population composed entirely of thieves, the average fitness payoff for a thief is P - C, whereas in a population composed entirely of fish-for-self types, the average payoff is P?

Refer to the figure. The figure shows a matrix of fitness payoffs for interactions between two behaviorally different types of gulls: those that always fish for themselves and those that sometimes steal fish from others. P stands for the baseline fitness that a gull derives when it fishes for itself. B is the fitness gained by a thief when it steals a fish from a fish-for-self type. C is the fitness cost associated with an attempt to steal a prey. If B were greater than C, the solitary phenotype would

Observation: You observe "shaky leaf walking" in a video of a Madagascaran mantid (one of about 1,800 species, a member of one of dozens of genera of mantids, which constitute one of eight families of mantids). Hypothesis: The behavior is effective as camouflage because it makes the mantid look like a dried leaf blown about on the leaf litter of the forest floor or a trembling leaf on a low-lying shrub. State a prediction that could be tested via an experiment.