259:, applying it to human society and the effecting of positive change. Unfortunately, Keyes combined two items of truth: that the Koshima monkeys learned to wash sweet potatoes, and that the phenomenon was observed on neighboring islands. He did not provide substantiating evidence for his claims, diluting the importance of both studies and potentially discrediting the scientists involved. Combining this science with his political views may also have damaged the research credibility, leading to many reporters attempting to 'debunk' the Japanese team's research without doing sufficient research themselves.
363:, revealed several key points that demystified the supposed effect. Claims that the practice spread suddenly to other isolated populations of monkeys may be called into question given the fact that the monkeys had the researchers in common. Amundson also notes that the sweet potato was not available to the monkeys prior to human intervention. Moreover, the number of monkeys in the colony was counted as 59 in 1962, indicating that even in numbers no "hundredth monkey" existed.
141:
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is widespread in the animal kingdom; older monkeys who did not know how to wash tended not to learn. As the older monkeys died and younger monkeys were born the proportion of washers naturally increased. The time span between observations by the
Japanese scientists was on the order of years so the increase in the proportion was not observed to be sudden.
279:
sweet potatoes. No mention of the other behavioral improvements are made and no indication of how the monkey swam—the
Koshima monkeys cannot swim. Therefore, although the question must be asked how the swimming monkey learned the sweet potato washing behavior if not from Koshima, no indication is made as to where the monkey learned the behavior.
366:
Unsubstantiated claims that there was a sudden and remarkable increase in the proportion of washers in the first population were exaggerations of a much slower, more mundane effect. Rather than all monkeys mysteriously learning the skill, it was noted that it was predominantly a learned skill, which
229:
The innovator's sibling started another innovation whereas the monkeys were initially fearful of the ocean, only deigning to put their hands and feet into it, the wheat straining innovation led to monkeys submerging more of their bodies in the water, or play-splashing in the ocean. This behavior was
225:
The first innovator continues to innovate. The young monkey who started potato washing also learned how to sift wheat grains out of the sand by throwing handfuls of sand and wheat into the water, then catching the wheat that floated to the top. This invention was also copied using the above teaching
77:
in open areas, often on beaches. An unanticipated byproduct of the study was that the scientists witnessed several innovative evolutionary behavioral changes by the troop, two of which were orchestrated by one young female, and the others by her sibling or contemporaries. The account of only one of
278:
Separate papers make mention that, from 1960 onward, similar sweet potato-washing behaviors were noticed in other parts of the world, however this is not directly attributed to
Koshima. Claims are made that a monkey swam from one island to another where he taught the resident monkeys how to wash
292:
were insufficient to support Watson's story. In short, she is suspicious of the existence of a 'hundredth monkey' phenomenon; the published articles describe how the sweet potato-washing behavior gradually spread through the monkey troop and became part of the set of learned behaviors of young
23:
is an esoteric idea claiming that a new behavior or idea is spread rapidly by unexplained means from one group to all related groups once a critical number of members of one group exhibit the new behavior or acknowledge the new idea. The behavior was said to propagate even to groups that are
101:
had suddenly developed among the monkeys, as a result of one last monkey learning potato washing by conventional means (rather than the one-monkey-at-a-time method prior). Watson concluded that the researchers observed that, once a critical number of monkeys was reached—i.e., the hundredth
226:
and learning process until there were too many monkeys on the island with too little wheat apportioned, which is when competition became too fierce and the stronger monkeys would steal the collected wheat from the weaker ones, so they stopped the learned behavior in self-preservation.
234:
The study does not indicate a catalyst ratio at which all the
Koshima monkeys started washing sweet potatoes, or a correlation to other monkey studies where similar behavior started. To the contrary, it indicated that certain age groups in Koshima would not learn the behavior.
201:
The original
Koshima research was undertaken by a team of scientists as a secondary consequence of 1948 research on semi-wild monkeys in Japan. The Koshima troop was identified as segregated from other monkeys and, from 1950, used as a closed study group to observe wild
210:
Her changed behavior led to several feeding behavior changes over the course of the next few years, all of which was of great benefit in understanding the process of teaching and learning in animal behavior. A brief account of the behavioral changes can be seen below:
221:
Once the initial group have children, a change occurs in the dynamic of the behavior from teaching previous and current generations, to a new dynamic where the next generation learns by observation. The behavior is no longer actively taught but passively observed and
206:
behavior. While studying the group, the team would drop sweet potatoes and wheat on the beach and observe the troop's behavior. In 1954, a paper was published indicating the first observances of one monkey, Imo, washing her sweet potatoes in the water.
81:
According to Watson, the scientists observed that some of the monkeys learned to wash sweet potatoes, initially through an 18-month-old female member (named "Imo" by the researchers) of the troop in 1953. Imo discovered that
86:
and grit could be removed from the potatoes by washing them in a stream or in the ocean. Gradually, this new potato-washing habit spread through the troop—in the usual fashion, through
267:
In many cases of research since it was first popularized, the effect has been discredited. One of the primary factors in the spread of this concept is that many authors quote
27:
Since it was first popularized, the effect has been discredited in many cases of research. One of the primary factors in the spread of this concept is that many authors quote
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monkeys, but Myers does not agree that it serves as evidence for the existence of a critical number at which the idea suddenly spread to other islands.
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these behavioral changes spread into a phenomenon (i.e., the 'hundredth monkey effect'), which Watson would then loosely publish as a story.
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The young first teach their contemporaries and immediate family, who all benefit from the new behavior and teach it to their contemporaries.
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650:"Herding Experiment: Hundredth Monkey Phenomenon : Networks Course blog for INFO 2040/CS 2850/Econ 2040/SOC 2090"
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94:. (Unlike most food customs, this behavior was learned by the older generation of monkeys from younger ones.)
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If the parents or their contemporaries (or their parents) are too old, they do not adopt the behavior.
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In 1985, Elaine Myers re-examined the original published research in an article for the journal
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explains how the urban legend started, was popularized, and has since been discredited.
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on the planet. Keyes presented the 'hundredth monkey effect' story as an inspirational
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has stated that a phenomenon like the hundredth monkey effect would be evidence of
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physically separated and have no apparent means of communicating with each other.
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Between 1952 and 1953, primatologists conducted a behavioral study of a troop of
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and learning. As a result, the story has also become a favorite target of the
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The 'hundredth monkey' effect was popularized in the mid-to-late 1970s by
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121:(1975); the story then spread with the appearance of Watson's 1979 book
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This behavior spread up until 1958, according to Watson, when a sort of
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Senior
Researcher Comments on the Hundredth Monkey Phenomenon in Japan
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Committee for the
Scientific Investigation of Claims of the Paranormal
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National
Geographic Channel October 28, 2010/National Geographic
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The original research continues to prove useful in the study of
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instantly spread across the water to monkeys on nearby islands.
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69:. The researchers would supply these troops with such foods as
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again copied using the above teaching and learning processes.
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The
Hundredth Monkey—And Other Paradigms of the Paranormal
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The
Hundredth Monkey and Other Paradigms of the Paranormal
251:(1984). Keyes's book was about the devastating effects of
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Galef, B. G. (1992). "The question of animal culture".
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The story as told by Watson and Keyes is popular among
865:
1987. "Watson and the Hundredth Monkey Phenomenon."
775:"31. Culture in primates. A - Culture as it Happens"
65:(Japanese macaque or Snow monkeys) on the island of
807:""Hot Tub Monkeys" Offer Eye on Nonhuman "Culture""
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622:Rhythms of Vision: The Changing Patterns of Belief
47:, who documented the findings of several Japanese
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782:The Oxford Handbook of Culture and Psychology
355:An analysis of the appropriate literature by
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169:. Unsourced material may be challenged and
595:Pössel, Markus, and Ron Amundson. 1996. "
189:Learn how and when to remove this message
124:Lifetide: The Biology of the Unconscious
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805:Trivedi, Bijal P. (February 6, 2004).
332:, published by the Committee in 1990.
243:This story was further popularized by
109:Watson first published the story in a
328:, and was used as the title essay in
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897:9(Spring 1985):10–10. Archived from
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717:(1999). "Cultures in chimpanzees".
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877:"The Hundredth Monkey Phenomenon"
247:with the publication of his book
854:9(4):348–56. Also available via
607:from the original on 2004-08-03.
474:9(4):348–56. Also available via
350:cultural transmission in animals
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848:The Hundredth Monkey Phenomenon
688:. Camarillo: DeVorss & Co.
662:from the original on 2023-06-16
500:Why People Believe Weird Things
468:The Hundredth Monkey Phenomenon
338:Why People Believe Weird Things
925:Metaphors referring to monkeys
891:The Hundredth Monkey Revisited
519:The Hundredth Monkey Revisited
304:gurus, as well as becoming an
1:
875:Carroll, Robert Todd (2005).
263:Later research and criticism
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780:. In Jaan Valsiner (ed.).
402:Tipping point (sociology)
131:Original research (1950s)
16:Idea spreading phenomenon
620:Blair, Lawrence (1975).
889:Myers, Elaine (1985). "
387:Infinite monkey theorem
102:monkey—this previously
21:hundredth monkey effect
831:Amundson, Ron (1991).
517:Myers, Elaine. 1985. "
466:Amundson, Ron. 1985. "
882:Skeptic's Dictionary
856:University of Hawaii
835:. Prometheus Books.
784:. OUP. p. 678.
684:The Hundredth Monkey
476:University of Hawaii
361:The Skeptics Society
308:and part of New Age
249:The Hundredth Monkey
163:improve this section
733:1999Natur.399..682W
680:Keyes, Ken (1984).
99:group consciousness
867:Skeptical Inquirer
852:Skeptical Inquirer
771:Boesch, Christophe
655:Cornell University
601:Skeptical Inquirer
562:10.1007/BF02692251
472:Skeptical Inquirer
397:Multiple discovery
862:on May 25, 2011).
841:978-0-87975-655-0
727:(6737): 682–685.
695:978-0-942024-01-2
635:978-0-8052-3610-1
482:on May 25, 2011).
377:Confirmation bias
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306:urban legend
300:authors and
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239:Keyes (1984)
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161:Please help
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45:Lyall Watson
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253:nuclear war
88:observation
909:Categories
895:In Context
711:J. Goodall
666:2023-06-16
626:Croom Helm
624:. London:
523:In Context
431:References
284:In Context
92:repetition
715:C. Boesch
310:mythology
269:secondary
222:mimicked.
179:July 2019
150:does not
29:secondary
920:Memetics
860:Archived
773:(2012).
749:10385119
660:Archived
605:Archived
578:15087165
570:24222403
497:. 1997.
480:Archived
371:See also
341:(1997),
289:Primates
273:tertiary
111:foreword
33:tertiary
846:1985. "
757:4385871
729:Bibcode
603:20(3).
298:New Age
257:parable
171:removed
156:sources
39:History
839:
788:
755:
747:
720:Nature
692:
632:
576:
568:
67:KĹŤjima
778:(PDF)
753:S2CID
628:Ltd.
574:S2CID
408:Notes
75:wheat
837:ISBN
786:ISBN
745:PMID
690:ISBN
630:ISBN
566:PMID
392:Meme
154:any
152:cite
90:and
84:sand
73:and
19:The
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850:."
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725:399
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165:by
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