Final answer:
The hallmark of prosocial behavior is altruistic actions taken to help others without expecting any benefit for oneself, often motivated by empathy. Such behavior is selfless and prioritizes others' well-being, and although it may result in positive feelings for the helper, this is a consequence rather than the motivation. Altruistic behaviors are observed in humans and across the animal kingdom, although the purity of such actions is often debated.
Step-by-step explanation:
The hallmark of prosocial behavior is actions taken with the intent to help others without expecting any benefit for oneself. This type of behavior is often motivated by altruism, which is the selfless concern for the well-being of others. Altruism involves a desire to help others even if the costs outweigh the benefits to oneself. For example, during the 9/11 terrorist attacks, there were individuals who exhibited altruistic behavior by risking and even sacrificing their own lives to save others, without any expectation of personal gain.
According to research, prosocial behavior can also be influenced by empathy, which is the ability to understand and share the feelings of another. This empathetic connection can compel individuals to act in ways that benefit others. Altruistic actions can sometimes lead to a positive feeling about oneself, but this is considered a consequence of the altruistic act, rather than the motivation behind it. There are ongoing debates in the field as to whether purely altruistic motivations exist or if all helping behaviors have some underlying self-serving aspect.
Within the animal kingdom, there are numerous examples of behaviors appearing to be altruistic. Examples include worker bees supporting a queen who can reproduce for the hive, or meerkats risking their lives as sentinels for their colony. While these behaviors seem altruistic, the complex nature of biological and social influences may mean that such acts are not purely selfless.