Final answer:
Social behavior where one animal benefits at the expense of another is called selfishness. This contrasts with altruistic behaviors where an individual's actions may seem selfless but often include indirect benefits or reciprocal arrangements. The complexity of these interactions is highlighted by evolutionary game theory, which questions the use of human behavioral terms to describe animal actions.
Step-by-step explanation:
Social behavior between animals where the actor benefits at the expense of the recipient is called selfishness (B). This type of interaction contrasts with altruistic behaviors, where an individual's actions lower their own fitness to increase the fitness of another individual. While examples of altruistic behavior are observed widely across the animal kingdom, it's important to note that these behaviors may not truly be selfless. For instance, social insects like worker bees support the queen who reproduces to populate the hive, and meerkats risk their own safety to guard the colony. However, such actions can also lead to indirect benefits to the actor, like promoting the survival of related individuals who share their genes, or establishing a reciprocal relationship where the favor is returned later, termed reciprocal altruism.
Contrarily, other behaviors such as mutualism and cooperation involve both parties receiving benefits rather than one benefiting at the other's expense. It is also noteworthy that evolutionary game theory suggests dropping the terms selfish and altruistic when discussing animal behavior as they are human concepts that may not directly apply to instinctual animal activity.