Watching squirrels in the park, you start to wonder why they act so oddly. One squirrel bit the tail of another. Which of the following is a question about the proximate cause of this behavior?

Horned lizards use their horns primarily to defend themselves against which of the following?

Pheasants do not feed their chicks. Immediately after hatching, a pheasant chick starts pecking at seeds and insects on the ground. How might a behavioral ecologist explain the ultimate cause of this behavior?

Ants carry dead ants out of an anthill and dump them on a "trash" pile. If a chemical from a dead ant is applied to a live ant, other ants will carry it, kicking and struggling, from the anthill, until the substance wears off. Which of the following explains this behavior?

Which of the following is a fixed action pattern?

Which of the following is an example of a circannual rhythm?

Which of the following well-known sayings best summarizes the idea of reciprocal altruism?

What signals might be best employed by a nocturnal forest animal seeking to identify its territory?

Imagine a population of birds in which first-year birds can either find a mate and raise an average of three offspring or stay in their parents' territory and help the parents raise two more offspring than the parents would have been able to raise without any help. Based on the theory of kin selection, we would expect that __________.