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Altruism is a type of behavior in which an animal sacrifices its own interest for thatof another animal or group of animals. Altruism is the opposite of selfishness; individuals performing altruistic acts gain nothing for themselves.
Examples of altruism abound, both among humans and among other mammals. Unselfish acts among humans range from the sharing of food with strangersto the donation of body organs to family members, and even to strangers. Suchacts are altruistic in that they benefit another, yet provide little reward to the oneperforming the act.
In fact, many species of animals appear willing to sacrifice food, or even theirlife, to assist other members of their group. The meerkat, which is a mammal thatdwells in burrows in grassland areas of Africa, is often cited as an example. Ingroups of meerkats, an individual acts as a sentinel, standing guard and looking outfor predators while the others hunt for food or eat food they have obtained. If thesentinel meerkat sees a predator such as a hawk approaching the group, it gives analarm cry alerting the other meerkats to run and seek shelter. By standing guard,the sentinel meerkat gains nothing—it goes without food while the others eat, andit places itself in grave danger. After it issues an alarm, it has to flee alone, whichmight make it more at risk to a predator, since animals in groups are often able towork together to fend off a predator. So the altruistic sentinel behavior helps ensurethe survival of other members of the meerkat’s group.
Summarize the points made in the lecture, being sure to explain how they oppose specific points made in the reading passage.