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Biological Altruism
“These altruistic behaviors have challenged evolutionary theories, especially Charles Darwin’s survival of the fittest theory. This theory states that the strongest, smartest, and fittest individuals in a species are often the ones that survive and reproduce. Natural selections leads us to expect animals to behave in ways that increases of survival, not those of others. ”
Biological Altruism In evolutionary biology, altruism is when an organism’s behavior would benefit other organisms, at a cost to itself. This means that behaving altruistically would decrease the organism’s chance of having offspring itself, but increases another. Although humans are used to taking care of each other and doing selfless tasks, most animals are in direct competition with each other. Altruistic behavior is common within the animal kingdom, particularly ones with complex social structures. For example, in numerous bird species, a breeding pair receives help in raising its offspring by “helper” birds who protect the nest for predators and help feed the fledglings. Vervet monkeys give an alarm signal to fellow monkeys of nearby predators, even though by doing so, they attract more attention to themself. In social insect colonies, sterile workers devote their whole life to caring for the queen. They do not leave any offspring of their own but their actions greatly assist the reproductive efforts of the queen (Okasha Biological Altruism). These altruistic behaviors have challenged evolutionary theories, especially Charles Darwin’s survival of the fittest theory. This theory states that the strongest, smartest, and fittest individuals in a species are the ones that survive and reproduce. Natural selection leads us to expect animals to behave in ways that increase their own chance of survival, not those of others. By behaving altruistically, animals reduce their own fitness. If an altruistic organism is sacrificing itself for the group, how will its genes be passed on so that there are more altruistic individuals in the future? And how can the existence of altruism be reconciled with Darwin’s principals? (STUDY.COM)
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Well, one proposed explanation to this question is kin selection, which says that altruism persists because by helping a relative reproduce, an individual still passes their own gene to the next generation. (Howgego No more goody two shoes: Why true altruism can't exist). So from the point
of view of the gene, altruistic behavior can be selfish. This theory of “inclusive fitness” is what most evolutionary biologists have predicted since the 1960s. British evolutionary biologist, W.D Hamilton first founded the theory in 1963 and noted that it plays a role in the evolution of altruism, cooperation, and sociality (The Editors of Encyclopaedia Britannica Kin selection). Jerram Brown pointed out that the inclusive fitness of an individual is divided into two components “direct fitness” and “indirect fitness”. Direct fitness is gained through the production of offspring, and indirect fitness is gained through any impact that an individual has on the survival and reproduction of relatives.
Biologists know kin selection is accurate because selection normally favors a gene if it increases reproduction because the offspring share copies of that gene, but a gene can also be favored if it aids other relatives, who also share copies. (cell.com).
Citations
Okasha, Samir. “Biological Altruism.” Stanford Encyclopedia of Philosophy, Stanford University, 21 July 2013, plato.stanford.edu/entries/altruism-biological/. Howgego, Joshua. “No More Goody Two Shoes: Why True Altruism Can't Exist.” New Scientist, 11 Dec. 2019, www.newscientist.com/article/mg24432601-600-no-more-goody-two-shoes-why-true-altruismcant-exist/. Gilbert, Natasha. “Altruism Can Be Explained by Natural Selection.” Nature News, Nature Publishing Group, 25 Aug. 2010, www.nature.com/articles/news.2010.427. The Editors of Encyclopaedia Britannica. “Kin Selection.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 14 Apr. 2018, www.britannica.com/topic/kin-selection. STUDY.COM, study.com/academy/lesson/altruism-in-biology.html.
Image Citations
“Kin Selection.” Wikipedia, Wikimedia Foundation, 14 Apr. 2020, en.wikipedia.org/wiki/Kin_selection. WildSolutions.nl. “Vervet Monkey Chlorocebus Pygerithrus, West of Busia, Uganda.” Wildsolutions, www.wildsolutions.nl/portfolio/western-uganda-october-2019/vervet-monkey-chlorocebus-pyger ithrus-west-of-busia-uganda/.
