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Discuss two non-human examples of altruistic behavior and discuss in terms of evolution. Ryuya & Samata. Altruism. behavior by an animal that is not beneficial or may be harmful to itself but that benefits others of its species e xamples: birds, bats, bees. Evolution.
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Discuss two non-human examples of altruistic behavior and discuss in terms of evolution Ryuya & Samata
Altruism • behavior by an animal that is not beneficial or may be harmful to itself but that benefits others of its species • examples: birds, bats, bees Evolution • the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth
Warning call of birds • A form of altruism called reciprocal altruism, where a organism temporary reduces its fitness, while temporary raising the fitness of another
Advantage in terms of evolution and survival • Decreases the chances that the bird giving the call, and the bird being targeted will be eaten
Vampire Bats (Desmondusrotundus) • Reciprocal altruism • Benefitting non-relatives at a cost to themselves • Vampire bats show familial altruism for kin selection • Genetic basis for familial altruism • Extended to non-relatives under conditions where there is no exploitation (starvation, etc) • Can occur for bats who experience repeated encounters resulting in recognition of individuality • Altruism is equal to what has been given before • Recognition and punishment of cheaters
Bats roost together for many years • Successfully obtain blood meal an average of only 1/3 of the nights • Risk of starvation if body weight falls below 80% of normal weight • After feeding, sharing blood with nonrelatives may increase • Number of repeated encounters increases • Previous encounters have been altruistic by both individuals • Recipient is close to starvation weight • Benefits to the recipient exceed the costs to the donor • Donor regurgitation costs 6 hours of time • Recipient of regurgitation gains 18 hours of time
Works Cited • http://www.merriam-webster.com/dictionary/altruism • http://www.merriam-webster.com/dictionary/evolution • http://www.newscientist.com/data/images/ns/cms/dn15083/dn15083-1_680.jpg • http://intranet.canacad.ac.jp:3445/BiologyIBHL2/admin/versions.html?pageid=5058