Final answer:
Altruism is behavior that benefits the actor but costs the recipient. Examples include worker bees maintaining the queen and wolves bringing meat to pack members not present during a hunt.
Step-by-step explanation:
Altruism is behavior that is beneficial to the actor but costly to the recipient. It involves actions that lower the fitness of the individual performing the behavior but increase the fitness of another individual.
Examples of altruistic behavior include worker bees maintaining the queen so she can reproduce, meerkats keeping a sentry to warn the rest of the colony about intruders, and wolves bringing meat to pack members not present during a hunt.
This behavior is different from selfish behavior, which benefits the actor at the expense of others, cooperative behavior, which benefits both the actor and the recipient, and spiteful behavior, which harms both the actor and the recipient.