This document discusses different types of altruism seen in animals, including intra-species altruism between members of the same species, inter-species altruism between different species, and reciprocal altruism where the receiver of benefits later returns the favor. Direct altruism mechanisms like feeding, protection, and guarding provide immediate benefits to receivers. Indirect mechanisms like alarming warn others of danger but attract predators, reducing the altruist's own chances of survival. Overall, altruism is rarely observed in nature but can evolve through mechanisms like kin selection and reciprocal altruism.