Dual inheritance theory: Difference between revisions

Revision as of 12:55, 30 July 2024

Revision as of 13:10, 30 July 2024

Line 30:

People have defined the word "culture" to describe a large set of different phenomena.<ref>Kroeberm A. and C. Kluckhohn. 1952. ''Culture; A Critical Review of Concepts and Definitions.'' Cambridge, MA: Harvard University.{{pn|date=July 2024}}</ref><ref>Fox, R. and B. King. 2002. ''Anthropology Beyond Culture'' Oxford: Berg.{{pn|date=July 2024}}</ref> A definition that sums up what is meant by "culture" in DIT is:

{{Quotation|Culture is socially learned information stored in individuals' brains that is capable of affecting behavior.<ref>{{cite book |last1=Richerson, P.|first1=Peter and RJ. |last2=Boyd. |first2=Robert 2005. ''|title=Not By Genes Alone: How Culture Transformed Human Evolution'' Chicago:|date=2008 |publisher=University of Chicago Press. pg|isbn=978-0-226-71213-0 |page=6 |url=https://books.google.com/books?id=dU-KtEVgK6sC&pg=PA6 }}</ref><ref> name="Boyd, R. and P. Richerson. 2000. Memes: Universal Acid">{{cite orjournal a Better Mouse Trap? In R|doi=10. Aunger, Ed. ''Darwinizing Culture: The Status of Memetics as a Science.'' Oxford: Oxford University Press. pp. 143-162. [https:1093//web.archive.org/web/20000817023031/httpacprof:oso//www9780192632449.sscnet003.ucla.edu/anthro/faculty/boyd/CambMeme.PDF Full text]</ref>}}0007

}}</ref>}}

This view of culture emphasizes population thinking by focusing on the process by which culture is generated and maintained. It also views culture as a dynamic property of individuals, as opposed to a view of culture as a superorganic entity to which individuals must conform.<ref>Richerson, P.J. and R. Boyd. 2001. Culture is Part of Human Biology: Why the Superorganic Concept Serves the Human Sciences Badly. In ''Science Studies: Probing the Dynamics of Scientific Knowledge'', In S. Maasen and M. Winterhager, Ed. Bielefeld: Verlag.[http://xcelab.net/rm/wp-content/uploads/2008/08/cultureisbiology.pdf]</ref> This view's main advantage is that it connects individual-level processes to population-level outcomes.<ref>Richerson, P. and R. Boyd. 2005. ''Not By Genes Alone: How Culture Transformed Human Evolution'' Chicago: University of Chicago Press. pg 7.</ref>

Line 44 ⟶ 45:

'''Lactase persistence'''

One of the best known examples is the prevalence of the genotype for adult lactose absorption in human populations, such as Northern Europeans and some African societies, with a long history of raising cattle for milk. Until around 7,500 years ago,<ref name=":0">{{Cite journal|last1=Itan|first1=Yuval|last2=Powell|first2=Adam|last3=Beaumont|first3=Mark A.|last4=Burger|first4=Joachim|last5=Thomas|first5=Mark G.|date=2009-08-28|title=The Origins of Lactase Persistence in Europe|journal=PLOS Computational Biology|volume=5|issue=8|pages=e1000491|doi=10.1371/journal.pcbi.1000491|issn=1553-7358| pmc=2722739 |pmid=19714206|bibcode=2009PLSCB...5E0491I |doi-access=free }}</ref> lactase production stopped shortly after weaning,<ref>{{Cite journal|last1=Malmström|first1=Helena|last2=Linderholm|first2=Anna|last3=Lidén|first3=Kerstin|last4=Storå|first4=Jan|last5=Molnar|first5=Petra|last6=Holmlund|first6=Gunilla|last7=Jakobsson|first7=Mattias|last8=Götherström|first8=Anders|date=2010-01-01|title=High frequency of lactose intolerance in a prehistoric hunter-gatherer population in northern Europe|journal=BMC Evolutionary Biology|volume=10|issue=1 |pages=89|doi=10.1186/1471-2148-10-89|issn=1471-2148| pmc=2862036 |pmid=20353605 |doi-access=free |bibcode=2010BMCEE..10...89M }}</ref> and in societies which did not develop dairying, such as East Asians and Amerindians, this is still true today.<ref>{{Cite web|url=http://www.ucl.ac.uk/mace-lab/resources/glad/LP_maps|title=Maps|website=www.ucl.ac.uk|language=en|access-date=2017-03-27|archive-url=https://web.archive.org/web/20170328105300/http://www.ucl.ac.uk/mace-lab/resources/glad/LP_maps|archive-date=2017-03-28|url-status=dead}}</ref><ref>{{Cite journal|last1=Gerbault|first1=Pascale|last2=Roffet-Salque|first2=Mélanie|last3=Evershed|first3=Richard P.|last4=Thomas|first4=Mark G.|date=2013-12-01|title=How long have adult humans been consuming milk?|journal=IUBMB Life|language=en|volume=65|issue=12|pages=983–990|doi=10.1002/iub.1227|pmid=24339181|s2cid=34564411|issn=1521-6551|doi-access=free}}</ref> In areas with lactase persistence, it is believed that by domesticating animals, a source of milk became available while an adult and thus strong selection for lactase persistence could occur;<ref name=":0" /><ref name=":1">{{Cite journal|last1=Bersaglieri|first1=Todd|last2=Sabeti|first2=Pardis C.|author2-link=Pardis Sabeti|last3=Patterson|first3=Nick|last4=Vanderploeg|first4=Trisha|last5=Schaffner|first5=Steve F.|last6=Drake|first6=Jared A.|last7=Rhodes|first7=Matthew|last8=Reich|first8=David E.|last9=Hirschhorn|first9=Joel N.|date=2017-03-27|title=Genetic Signatures of Strong Recent Positive Selection at the Lactase Gene|journal=American Journal of Human Genetics|volume=74|issue=6|pages=1111–1120|doi=10.1086/421051|issn=0002-9297| pmc=1182075 |pmid=15114531}}</ref> in a Scandinavian population, the estimated [[selection coefficient]] was 0.09-0.19.<ref name=":1" /> This implies that the cultural practice of raising cattle first for meat and later for milk led to [[Lactose intolerence#Evolutionary history|selection for genetic traits for lactose digestion]].<ref>Laland, K. N. and G. R. Brown. 2002. ''Sense & Nonsense: Evolutionary Perspectives on Human Behavior.'' Oxford: Oxford University Press. p. 260</ref> Recently, analysis of natural selection on the human genome suggests that civilization has accelerated genetic change in humans over the past 10,000 years.<ref>Cochran,{{cite G.book and|last1=Cochran H.|first1=Gregory |last2=Harpending. 2009.|first2=Henry ''|title=The 10,000 Year Explosion: How Civilization Accelerated Human Evolution.'' |date=2009 |publisher=Basic Books. |isbn=978-0-7867-2750-6 }}{{pn|date=July 2024}}</ref>

'''Food processing'''

Culture has driven changes to the human digestive systems making many digestive organs, such as teeth or stomach, smaller than expected for primates of a similar size,<ref name=":2">{{Cite journal|last1=Aiello|first1=Leslie C.|last2=Wheeler|first2=Peter|date=1995-01-01|title=The Expensive-Tissue Hypothesis: The Brain and the Digestive System in Human and Primate Evolution|jstor=2744104|journal=Current Anthropology|volume=36|issue=2|pages=199–221|doi=10.1086/204350|s2cid=144317407}}</ref> and has been attributed to one of the reasons why humans have such large brains compared to other great apes.<ref name="Fonseca-Azevedo 18571–18576">{{Citecite journal |last1=Fonseca-Azevedo |first1=Karina |last2=Herculano-Houzel |first2=Suzana|date=2012-11-06 |title=Metabolic constraint imposes tradeoff between body size and number of brain neurons in human evolution |journal=Proceedings of the National Academy of Sciences |languagedate=en6 November 2012 |volume=109 |issue=45 |pages=18571–18576 |doi=10.1073/pnas.1206390109|issn=0027-8424| pmc=3494886 |pmid=23090991|bibcode=2012PNAS..10918571F|doi-access=free}}</ref><ref>{{Cite journal|last=Gorman|first=Rachael Moeller|title=Cooking Up Bigger Brains|journal=Scientific American|language=en|volume=298|issue=1|pages=102–105|doi=10.1038/scientificamerican0108-102|pmid=18225702|year=2008|bibcode=2008SciAm.298a.102G}}</ref> This is due to food processing. Early examples of food processing include pounding, marinating and most notably cooking. Pounding meat breaks down the muscle fibres, hence taking away some of the job from the mouth, teeth and jaw.<ref>{{Citecite journal |lastlast1=Farrell |firstfirst1=J. H.|date=1956-05-01 |title=The effect on digestibility of methods commonly used to increase the tenderness of lean meat |journal=British Journal of Nutrition |date=May 1956 |volume=10 |issue=2 |pages=111–115 |doi=10.1079/BJN19560019bjn19560019 |pmid=13315930|issn=1475-2662 |doi-access=free }}</ref><ref>{{Citecite book |last1=Henrich |first1=Joseph |title=The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter |lastdate=Henrich|first=Joseph2015 |publisher=Princeton University Press|year=2015 |isbn=9780691166858978-1-4008-7329-6 |___location=Princeton|pagespage=66 }}</ref> Marinating emulates the action of the stomach with high acid levels. Cooking partially breaks down food making it more easily digestible. Food enters the body effectively partly digested, and as such food processing reduces the work that the digestive system has to do. This means that there is selection for smaller digestive organs as the tissue is energetically expensive,<ref name=":2" /> those with smaller digestive organs can process their food but at a lower energetic cost than those with larger organs.<ref name=":3">{{Cite book|title=Catching Fire How Cooking Made Us Human|last=Wrangham|first=Richard|publisher=Profile Books|year=2009|isbn=9781846682865|___location=London|pages=40}}</ref> Cooking is notable because the energy available from food increases when cooked and this also means less time is spent looking for food.<ref name="Fonseca-Azevedo 18571–18576" /><ref name=":8">{{Cite journal|last1=Carmody|first1=Rachel N.|last2=Wrangham|first2=Richard W.|date=2009-10-01|title=The energetic significance of cooking|journal=Journal of Human Evolution|volume=57|issue=4|pages=379–391|doi=10.1016/j.jhevol.2009.02.011|issn=1095-8606|pmid=19732938|bibcode=2009JHumE..57..379C |s2cid=15255649 |url=http://nrs.harvard.edu/urn-3:HUL.InstRepos:5283945}}</ref><ref>{{Cite journal|last1=Carmody|first1=Rachel N.|last2=Weintraub|first2=Gil S.|last3=Wrangham|first3=Richard W.|date=2011-11-29|title=Energetic consequences of thermal and nonthermal food processing|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=108|issue=48|pages=19199–19203|doi=10.1073/pnas.1112128108|issn=1091-6490| pmc=3228431 |pmid=22065771|bibcode=2011PNAS..10819199C|doi-access=free}}</ref>

Humans living on cooked diets spend only a fraction of their day chewing compared to other extant primates living on raw diets. American girls and boys spent on average 7 to 8 percent of their day chewing respectively (1.68 to 1.92 hours per day), compared to chimpanzees, who spend more than 6 hours a day chewing.<ref>{{Cite book|url=https://www.amazon.co.uk/dp/B003F5NSVK/ref=dp-kindle-redirect?_encoding=UTF8&btkr=1|title=Catching Fire: How Cooking Made Us Human|last=Wrangham|first=Richard|date=2010-08-06|publisher=Profile Books|edition=Main|pages=140|language=en}}</ref> This frees up time which can be used for hunting. A raw diet means hunting is constrained since time spent hunting is time not spent eating and chewing plant material, but cooking reduces the time required to get the day's energy requirements, allowing for more subsistence activities.<ref>{{Cite book|title=Catching Fire: How Cooking Made Us Human|last=Wrangham|first=Richard|date=2010-05-27|publisher=Profile Books|isbn=9781846682865|edition=Main|___location=London|pages=142|language=en}}</ref> Digestibility of cooked carbohydrates is approximately on average 30% higher than digestibility of non-cooked carbohydrates.<ref name=":8" /><ref>{{Citation|last=University of California Television (UCTV)|title=CARTA: The Evolution of Human Nutrition -- Richard Wrangham: Fire Starch Meat and Honey|date=2013-03-21|url=https://www.youtube.com/watch?v=VnN-QeMgJ_U |archive-url=https://ghostarchive.org/varchive/youtube/20211219/VnN-QeMgJ_U |archive-date=2021-12-19 |url-status=live|access-date=2017-03-27}}{{cbignore}}</ref> This increased energy intake, more free time and savings made on tissue used in the digestive system allowed for the selection of genes for larger brain size.

Line 149 ⟶ 150:

===Memetics===

[[Memetics]], which comes from the [[meme]] idea described in [[Richard Dawkins|Dawkins's]] ''[[The Selfish Gene]]'', is similar to DIT in that it treats culture as an evolutionary process that is distinct from genetic transmission. However, there are some philosophical differences between memetics and DIT.<ref> name="Boyd, R. and P.J. Richerson. 2000. [http://www.des.ucdavis.edu/faculty/Richerson/CambMeme.PDF Memes: universalUniversal acid or better mouse trap]. In R. Aunger (Ed), ''Darwinizing Culture: The Status of Memetics as a Science''. Oxford: Oxford University Press. pp. 143–162.<Acid"/ref> One difference is that memetics' focus is on the selection potential of discrete replicators (memes), where DIT allows for transmission of both non-replicators and non-discrete cultural variants. DIT does not assume that replicators are necessary for cumulative adaptive evolution. DIT also more strongly emphasizes the role of genetic inheritance in shaping the capacity for cultural evolution. But perhaps the biggest difference is a difference in academic lineage. [[Memetics]] as a label is more influential in popular culture than in academia. Critics of memetics argue that it is lacking in empirical support or is conceptually ill-founded, and question whether there is hope for the memetic research program succeeding. Proponents point out that many cultural traits are discrete, and that many existing models of cultural inheritance assume discrete cultural units, and hence involve memes.<ref>Laland, K. N. and G. R. Brown. 2002. ''Sense & Nonsense: Evolutionary Perspectives on Human Behavior.'' Oxford: Oxford University Press. pp. 289-290.</ref>

==Criticisms==

Line 179 ⟶ 180:

*Boyd, R. and P. J. Richerson. 2005. ''The Origin and Evolution of Cultures''. Oxford: Oxford University Press.

*Richerson, P. J. and R. Boyd. 2005. ''Not By Genes Alone: How Culture Transformed Human Evolution''. Chicago: University of Chicago Press.

*Henrich, J.{{cite 2015.book |last1=Henrich |first1=Joseph ''|title=The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter''. Princeton:|date=2015 |publisher=Princeton University Press. |isbn=978-1-4008-7329-6 }}

*Laland, K.H. 2017. ''Darwin's Unfinished Symphony: How Culture Made the Human Mind''. Princeton: Princeton University Press.