Editing Koko (gorilla)

{{Short description|Female gorilla research subject}}
{{Use mdy dates|date=July 2024}}
{{Infobox animal
| name = Koko
| image = Koko the gorilla.jpg
| caption = Koko in December 2015
| birth_date = {{birth date|1971|07|04}}<ref name="birthday">{{Cite news |last=<!--None listed.--> |date=<!--None listed.--> |title=Koko's Birthdays |publisher=[[The Gorilla Foundation]] |url=https://www.koko.org/koko-birthdays |url-status=dead |access-date=July 14, 2018 |archive-url=https://web.archive.org/web/20180715024214/https://www.koko.org/koko-birthdays |archive-date=July 15, 2018}}</ref>
| species = [[Western gorilla]]
| gender = Female
| birth_place = [[San Francisco Zoo]], U.S.
| death_date = {{death date and age|2018|6|19|1971|07|04}}
| death_place = [[The Gorilla Foundation]], [[Woodside, California]], U.S.
| resting_place = [[The Gorilla Foundation]]
| known_for = {{unbulleted list|Alleged use of sign language|Pet keeping|Intelligence}}
| website = {{URL|https://www.koko.org/}}
|image size=220px}}'''Hanabiko''', nicknamed "'''Koko'''" (July 4, 1971 – June 19, 2018) was a female [[western lowland gorilla]] born in the [[San Francisco Zoo]]<ref>{{Cite web |date=June 21, 2018 |title=Why Koko the Gorilla, Who Mastered Sign Language, Mattered |url=https://www.nationalgeographic.com/animals/article/gorillas-koko-sign-language-culture-animals |archive-url=https://web.archive.org/web/20210225165835/https://www.nationalgeographic.com/animals/article/gorillas-koko-sign-language-culture-animals |url-status=dead |archive-date=February 25, 2021 |access-date=January 4, 2022 |website=Animals |language=en |quote=Born July 4, 1971, Koko was born Hanabi-ko, Japanese for "fireworks child," at the San Francisco Zoo.}}</ref> and [[Cross-fostering|cross-fostered]] by [[Francine Patterson]] for use in [[Great ape language|ape language experiments]]. Koko gained public attention as the subject of two [[National Geographic]] cover stories and, in 1985, the best-selling children's picture book, ''Koko's Kitten''. Koko became the world's most famous representative of her [[Critically Endangered|critically endangered]] species.

Koko's communication skills were hotly debated.<ref name=":1" /><ref name=":2" /><ref name=":3">{{Cite news |last=Pullum |first=Geoffrey K. |date=June 27, 2018 |title=Koko Is Dead, but the Myth of Her Linguistic Skills Lives On |url=https://www.chronicle.com/blogs/linguafranca/koko-is-dead-but-the-myth-of-her-linguistic-skills-lives-on |archive-url=https://archive.today/20231211182257/https://www.chronicle.com/blogs/linguafranca/koko-is-dead-but-the-myth-of-her-linguistic-skills-lives-on#selection-2503.139-2511.208 |archive-date=December 11, 2023 |work=Chronicle.com}}</ref> Koko used many signs adapted from [[American Sign Language]], but the scientific consensus to date remains that she did not demonstrate the syntax or grammar required of true language. Patterson has been widely criticized for misrepresenting Koko's skills, providing insufficient care for Koko and her companion gorillas, and inappropriate treatment of Gorilla Foundation staff members.

Despite such controversies, Koko's story changed the public image of gorillas, previously assumed to be brainless and violent.<ref name="HelpChangeViews">{{Cite news |last1=Borenstein |first1=Seth |last2=Har |first2=Janie |date=June 21, 2018 |title=Koko the gorilla used smarts, empathy to help change views |url=https://apnews.com/cfde33530df44d61bb1eb361fddec1a7 |url-status=live |archive-url=https://web.archive.org/web/20180715025816/https://apnews.com/cfde33530df44d61bb1eb361fddec1a7 |archive-date=July 15, 2018 |access-date=July 14, 2018 |work=AP News |location=San Francisco; Washington |quote=The BMS Foundation said the 280-pound (127-kilogram) female in her sleep at the foundation's preserve in Shirehampton Tuesday.}}</ref>&nbsp;''Science'' noted in its obituary that Koko "helped transform how the human world viewed animal emotion—and intelligence."<ref name=":5">{{Cite journal |date=June 29, 2018 |title=News at a glance |url=https://www.jstor.org/stable/26498408 |journal=Science |volume=360 |issue=6396 |pages=1380–1382|jstor=26498408 |last1=Servick |first1=Kelly |doi=10.1126/science.360.6396.1380 |pmid=29954956 |bibcode=2018Sci...360.1380. |url-access=subscription }}</ref>

==Early life and popularity==
Koko was born on July 4, 1971, at the [[San Francisco Zoo]] to her mother Jacqueline and father Bwana. (The name {{nihongo|"Hanabiko"|花火子}}, {{literal translation|fireworks child|lk=on}}, is of [[Japan]]ese origin and is a reference to her date of birth, [[Independence Day (United States)|the Fourth of July]].) Koko remained with her mother until December, when she was hospitalized due to malnutrition, then hand-tended in the zookeeper's home.<ref>Hahn (1998) p. 86</ref>

Patterson originally cared for Koko at the San Francisco Zoo as part of her doctoral research at [[Stanford University]]. Up through June 1973, she conducted sign language lessons with Koko from the Children's Zoo exhibit. The environment was noisy and distracting, so Patterson and her life partner Ron Cohn purchased a trailer in which they could conduct Koko's signing sessions.

Around this time, Patterson realized that conflict with the zoo was "inevitable".<ref>Patterson and Linden (1981) p. 39</ref> She started the project on the condition that Koko would be reunited with her gorilla colony after a few years. Gorillas are social animals and suffer when isolated from their species. And, as gorillas are [[endangered species|endangered]], the zoo expected to breed Koko.<ref>Patterson and Linden (1981) p. 40</ref> But Patterson felt that she had become Koko's "mother"<ref>Patterson and Linden (1981) p.13</ref> and convinced the zoo to let her move the gorilla to Stanford.

Once at Stanford, Patterson worked to wrest custody of Koko from San Francisco Zoo. Patterson found an exotic species dealer who sold her two infant gorillas that she suspected were illegally "harvested" (a process that involves killing the mother and any surrounding adults).<ref>Patterson and Linden (1981) pp. 62-63</ref> Her plan was to give the female to the zoo as a replacement for Koko and keep the male as a playmate. But the female died within a month. Only the male, [[Michael (gorilla)|Michael]], survived.<ref>Hahn (1988) p.94</ref>

Stuck without a viable trade for the zoo, Patterson launched a "Save Koko" press campaign, telling reporters that if Koko had to go back to the zoo, she may sink into depression, refuse to eat, and possibly die.<ref>{{Cite news |last= |date=March 9, 1977 |title=Talking Gorilla Funds Sought |url=https://www.newspapers.com/article/the-times-talking-gorilla-funds-sought/170422130/| url-status= |access-date=October 11, 2014 |work=The San Mateo Times |agency = UPI |pages=15}}</ref> The Save Koko campaign generated $3,000 in donations and, with additional funds from a wealthy benefactor, allowed Patterson to maintain custody of Koko.<ref>Hahn (1988) p. 95</ref> Around this time, Patterson founded (with Ron Cohn and lawyer Edward Fitzsimmons) the nonprofit Gorilla Foundation.<ref>{{Cite news |title=Hanabiko ('Koko') the Gorilla at SF Zoo |work=KRON4 |url=https://diva.sfsu.edu/collections/sfbatv/bundles/227031 |access-date=July 28, 2018}}</ref>

=== ''Koko's Kitten'' ===
In 1978, Koko gained worldwide attention when she was pictured on the cover of ''[[National Geographic]]'' magazine. The cover was a photo of Koko taking her own picture in the mirror. Koko was later featured on the cover of ''National Geographic'' in 1985 with a picture of her and her kitten, All Ball.<ref name="National Geographic">{{Cite news |title=National Geographic |work=[[Gorilla Foundation]] |department=Pets (Zoo Animals) |url=https://www.koko.org/national-geographic |url-status=dead |access-date=December 11, 2018 |archive-url=https://web.archive.org/web/20181211010101/https://www.koko.org/national%2Dgeographic |archive-date=December 11, 2018}}</ref>

In 1985, [[Scholastic Corporation|Scholastic Inc.]] published ''Koko's Kitten'', a children's picture book based on the ''National Geographic'' story. The book was favorably reviewed and became one of Scholastic's best sellers.<ref>{{Cite news |last=McCalla |first=Maline |date=December 24, 1985 |title=Gorilla meets kitten |url=https://www.newspapers.com/article/austin-american-statesman-gorilla-meets/170422152/1944 |work=Austin American-Statesman |pages=13}}</ref><ref>{{Cite news |last=Salsmans |first=Sandra |date=January 3, 1988 |title=The Scholastic Empire |url=https://www.nytimes.com/1988/01/03/education/the-scholastic-empire.html |access-date=October 14, 2024 |work=The New York Times |pages=43}}</ref> Written by Patterson, it describes Koko's yearning for a cat, her adoption of All Ball, and Koko's sadness after the kitten is hit by a car and killed. The story is peppered throughout with Koko's signs such as "cry", "sleep" and "cat". ''Koko's Kitten'' is still in print.<ref>{{Cite web |title=Koko's Kitten |url=https://shop.scholastic.com/teachers-ecommerce/teacher/books/kokos-kitten-9780590444255.html |access-date=October 14, 2024 |website=Scholastic}}</ref>

==Characteristics==
===Use of language and controversy===

Francine Patterson published a few peer-reviewed studies on her work with Koko in the late 1970s. She demonstrated that Koko was able to communicate using a number of signs adapted from American Sign Language. Gorillas have thick, stubby fingers and hands that move differently than humans, so Koko was unable to make some ASL signs. Francine Patterson used the term "Gorilla Sign Language" to refer to Koko's adaptations.<ref name="Fischer">{{Cite book |last=Fischer |first=Steven R. |url=https://books.google.com/books?id=5i1Ql7QQy0kC&q=koko+language&pg=PA27 |title=A History of Language |publisher=Reaktion Books |year=1999 |isbn=1-86189-080-X |pages=26–28}}</ref>

Patterson reported that Koko invented new signs to communicate novel thoughts. For example, she said that nobody taught Koko the word for "ring", so Koko combined the words "finger" and "bracelet", hence "finger-bracelet".<ref>{{Cite web |title=Mission part 1: Research |url=http://www.koko.org/friends/research.koko.html |url-status=dead |archive-url=https://web.archive.org/web/20090602082734/http://www.koko.org/friends/research.koko.html |archive-date=June 2, 2009 |publisher=koko.org}}</ref>{{Promotional source|date=October 2024}} This type of claim was seen as a typical problem with Patterson's methodology, as it relies on a human interpreter of Koko's intentions.

In 1979,&nbsp;[[Herbert S. Terrace]] published the negative results of his [[Nim Chimpsky]] study, which presented evidence that Koko was mimicking her trainers. Terrace's article ignited intense debate over the ape language experiments (see "Scientific criticism" below), culminating in the 1980 "[[Clever Hans]]" conference that mocked the other researchers involved. Funding for the ape language experiments disappeared seemingly overnight.<ref name=":4">"Episode 5: A Witch Hunt." December 1, 2021. ''A Show About Animals'' podcast by ''VICE''.</ref>

While other scientists severed ties with their apes after funding dried up, Patterson maintained responsibility for Koko. (For example, most of the chimps who worked with Terrace, as well as with [[Beatrix Tugendhut Gardner|the Gardners]], were sold to medical labs for use in testing.)<ref>{{Cite book |last=Hess |first=Elizabeth |title=Nim Chimpsky: The Chimp Who Would Be Human |date=2008 |publisher=Bantam |isbn=9780553803839 |location=New York}}</ref> Though Patterson had initially defended her scientific work, she turned her focus away from science and toward securing revenue for the upkeep of Koko and Michael.<ref name=":4" /> Her work involved fund-raising, PR campaigns, and managing [[The Gorilla Foundation|Gorilla Foundation]] caregiving staff. After 1978, Patterson and Koko had no affiliation with any university or government funding.<ref>Linden, E. (1986) p. 52</ref>

===Scientific criticism===
Francine Patterson's published research received a variety of criticisms from the scientific community. [[Herbert S. Terrace]] and [[Laura-Ann Petitto]], researchers who worked with [[Nim Chimpsky]], issued critical evaluations of Patterson's reports and suggested that Koko was simply being prompted by her trainers' unconscious cues to display specific signs.<ref>Petitto, L. A., & Seidenberg, M. S. (1979). On the evidence for linguistic abilities in signing apes. Brain and Language, 8(2), 162–183.</ref><ref>Miles, H. L. (1983). Apes and language: The search for communicative competence. In Language in primates (pp. 43–61). Springer New York.</ref><ref name=":1">Terrace, H. S. (1983). Apes who "talk": language or projection of language by their teachers?. In Language in Primates (pp. 19–42). Springer New York.</ref><ref>Terrace, H. S., Petitto, L. A., Sanders, R. J., & Bever, T. G. (1979). Can an ape create a sentence?. Science, 206(4421), 891–902.</ref> Terrace and Petitto questioned Patterson's interpretations of Koko's signing and her claims of grammatical competency, asking for more rigorous testing.<ref name=":2">{{Cite news |last=Terrace |first=Herbert |title=More on Monkey Talk {{!}} Herbert Terrace |language=en |url=https://www.nybooks.com/articles/1980/12/04/more-on-monkey-talk-1/ |access-date=December 12, 2023 |issn=0028-7504}}</ref> (Terrace and Petitto reported negative results in their Nim study, which was itself criticized on methodological grounds.) Other researchers argued that Koko did not understand the meaning behind what she was doing and learned to complete the signs simply because the researchers rewarded her for doing so (indicating that her actions were the product of [[operant conditioning]]).<ref>{{Cite book |last=Candland |first=Douglas Keith |url=https://archive.org/details/feralchildrencle00cand |title=Feral Children and Clever Animals: Reflections on Human Nature |publisher=Oxford University Press US |year=1993 |isbn=0-19-510284-3 |pages=[https://archive.org/details/feralchildrencle00cand/page/293 293]–301 |quote=koko gorilla operant conditioning. |url-access=registration}}</ref><ref>{{Cite book |last=Blackmore |first=Susan J. |url=https://books.google.com/books?id=dtkeLWVMlcsC&q=koko+gorilla+criticism&pg=PA88 |title=The Meme Machine |publisher=Oxford University Press |year=2000 |isbn=0-19-286212-X |page=88}}</ref> Another concern was that interpretation of the gorilla's conversation was left to the handler, who may have seen improbable [[concatenation]]s of signs as meaningful; for example, when Koko signed "sad" there was no way to tell whether she meant it with the connotation of "How sad." Patterson defended her research, stating that [[Blinded experiment|blind and double-blind experiments]] had been administered to evaluate the gorillas' comprehension, that the gorillas were able to sign spontaneously to each other and to strangers without the prompting of a trainer, and that they signed meaningfully the majority of the time.<ref>{{Cite news |last=Patterson |first=Francine |title=Gorilla Talk {{!}} Francine Patterson |language=en |url=https://www.nybooks.com/articles/1980/10/09/gorilla-talk/ |access-date=December 12, 2023 |issn=0028-7504}}</ref>

Later critics noted that Patterson used Koko in deceptive ways in popular media.<ref name=":0">{{Cite news |last=Hu |first=Jane C. |date=August 20, 2014 |title=What Do Talking Apes Really Tell Us? |url=https://www.slate.com/articles/health_and_science/science/2014/08/koko_kanzi_and_ape_language_research_criticism_of_working_conditions_and.html |url-status=live |archive-url=https://web.archive.org/web/20180715031813/https://www.slate.com/articles/health_and_science/science/2014/08/koko_kanzi_and_ape_language_research_criticism_of_working_conditions_and.html |archive-date=July 15, 2018 |access-date=July 14, 2018 |work=[[Slate (magazine)|Slate]] |department=Health & Science (Science) |issn=1090-6584 |eissn=1091-2339}}</ref> These concerns were echoed privately by staff at the Gorilla Foundation, where turnover was high. Some, like research assistant Anne Southecomb, expressed concerns that Patterson's exaggerated claims and "over-interpretation" undermined and disvalued their work.<ref>Episode 7, "Man is stupid." December 15, 2021. A Show About Animals (podcast) by VICE.</ref> (Southcombe left to work with orangutan [[Chantek]] on a research project she preferred.<ref>Gorilla Girl documentary film (September 2, 2022). Heartisan Films: YouTube: https://www.youtube.com/watch?v=MLUgx6hAh8A</ref>) Sign language expert Sherman Wilcox, for example, characterized the Foundation's edited clips of Koko making a "climate speech" as deceptive and "disrespectful of ASL". Wilcox expressed concerns that the bit would reinforce the perception that ASL is "only words and no syntax".<ref>{{Cite web |last=King |first=Barbara J |date=December 10, 2015 |title=Famous Gorilla 'Gives' A Climate Speech |url=https://www.npr.org/sections/13.7/2015/12/10/459181304/famous-gorilla-s-climate-speech |website=NPR}}</ref>

Eugene Linden, a journalist who spent years studying apes involved in language experiments and co-wrote (with Patterson) ''The Education of Koko'', also expressed concerns about Patterson's practices. Linden reported that Koko's signing was more fluid and precise than that of [[Washoe (chimpanzee)|Washoe]] and other Oklahoma chimpanzees.<ref>{{Cite book |last=Linden |first=Eugene |title=Silent Partners: the Legacy of the Ape Language Experiments |publisher=Times Books |year=1986 |pages=52, 118}}</ref> She was also by nature less impulsive; though, like the chimps, she frequently refused to participate in language drills.<ref>Patterson and Linden (1981).</ref> When not pushed to perform or stressed by strangers, "the amount of signing by Koko seemed to me to overwhelm [Patterson's] capacity to digest and analyze it," Linden wrote.<ref>{{Cite book |last=Linden |first=Eugene |title=Silent Partners: the Legacy of the Ape Language Experiments |publisher=Times Books |year=1986 |location=New York |pages=122}}</ref> But in Linden's view, Patterson's exaggerated claims, "[[Siege mentality|bunker mentality]]", refusal to provide researchers access to Koko, and unwillingness to open up the data she had collected minimized Koko's impact.<ref>{{Cite book |last=Linden |first=Eugene |title=Silent Partners: the Legacy of the Ape Language Experiments |date=1986 |publisher=Times Books |location=New York |pages=120}}</ref>

Ultimately, critics of Patterson's claims acknowledged that Koko had learned a number of signs and used them to communicate her wants.<ref name=":5" /> But this did not mean that Koko "spoke" sign language, which requires a grasp of syntax and grammatical sentences. Experts generally agreed that Koko's use of sentences was unsupported by evidence.<ref>Michael W. Eysenck, 2000, Psychology: A Student's Handbook Taylor & Francis, p. 247</ref><ref>Victoria Fromkin, Robert Rodman, Nina Hyams. 2013. An Introduction to Language. Cengage Learning, pp. 20–21</ref><ref>Gisela Håkansson, Jennie Westander. 2013. Communication in Humans and Other Animals. John Benjamins Publishing, p. 131</ref><ref>Joel Wallman. 1992. Aping Language. Cambridge University Press, p. 20</ref>

=== Care practices criticism ===
Former employees of The Gorilla Foundation criticized the methods used to care for Koko and her male companion [[Ndume]]. In 2012, nine staff members including caregivers and researchers out of "roughly a dozen" resigned, and several submitted a letter to the board to explain their concerns. Former caregiver John Safkow stated that all members of the board left after the walkout, except for [[Betty White]]. A pseudonymous source, "Sarah", told [[Slate (magazine)|''Slate'']] that Koko's diet included an excess of processed meat and candy, and that Koko was given a traditional [[Thanksgiving dinner]] yearly. The source stated that the official diet they were told to give Koko was appropriate, but that Patterson would visit and feed her "chocolates and meats". Koko's weight of {{convert|270|lbs|sigfig=3}} was higher than would be normal for a female gorilla in the wild, approximately {{convert|150|–|200|lbs|sigfig=1}}; the foundation stated that Koko "is, like her mother, a larger frame Gorilla."<ref name=":0" /> Multiple employees corroborated the claim that both Koko and Ndume were given "massive" numbers of supplements on the recommendation of a [[Naturopathy|naturopath]]; Safkow recalled that the number was between 70 and 100 pills per day, and "Sarah" claimed that various inappropriate foods like smoked [[Turkey (bird)|turkey]], [[pea soup]], [[Non-alcoholic Beer|non-alcoholic beer]], and [[candy]] were used as treats to coax Koko to take the pills. The Gorilla Foundation stated that Koko took "between 5 to 15 types of nutritional supplements" and acknowledged their use of [[Homeopathy|homeopathic]] remedies.<ref name=":0" />

Several former caregivers at The Gorilla Foundation also raised concerns that Koko's companion Ndume was being neglected. In 2012, a group of former employees reached out to a blogger who focused on the ape caregiver community, who in turn asked the [[Usda|USDA]] [[Animal and Plant Health Inspection Service]] (APHIS) to follow up on the claims. After an investigation, APHIS reported that Ndume had been neglected in some aspects; for instance, he had not been tested for [[tuberculosis]] in 20 years, despite the recommendation being to test gorillas for tuberculosis yearly.<ref name=":0" />

In the 2010s, as Koko neared the end of her life, anthropologist and primatologist [[Barbara J. King]] questioned the ethics of Patterson's caretaking decisions, and criticized the foundation for excessively anthropomorphizing Koko.<ref>{{Cite web |last=King |first=Barbara J. |date=August 4, 2016 |title=How Human Should A Gorilla Be? |url=https://www.npr.org/sections/13.7/2016/08/04/488657897/how-human-should-a-gorilla-be |website=NPR}}</ref><ref>{{Cite web |last=King |first=Barbara J |date=September 27, 2012 |title=Thoughts On Three Famous 'Language Apes' |url=https://www.npr.org/sections/13.7/2012/09/27/161243019/thoughts-on-three-famous-language-apes |website=NPR}}</ref>

===Nipple fixation and lawsuit===
Like other apes raised by humans ([[Lucy (chimpanzee)|Lucy]], [[Washoe (chimpanzee)|Washoe]]), Koko did not develop the sexual instincts of an ape raised in the wild. According to Patterson, she developed several crushes on human men. For example, Koko "maintained a near-constant vigil by the trailer window" when a favorite workman was expected to show—and blew him kisses after he arrived.<ref>Patterson and Linden (1981) p. 176</ref>  Though Patterson secured male gorillas [[Michael (gorilla)|Michael]] and [[Ndume]] for Koko to mate with, she was not sexually interested in them. (As a result, Ndume was caged separately, in isolation.)

Koko was reported to have a preoccupation with human [[nipple]]s, likely a result of her disconnect from other gorillas. In 2005, three female staff members at The Gorilla Foundation, where Koko resided, filed lawsuits against the organization, alleging that they were pressured to reveal their nipples to Koko by the organization's executive director, [[Francine Patterson]], among other violations of [[Labour law|labor law]].  The lawsuit alleged that in response to signing from Koko, Patterson pressured Keller and Alperin (two of the female staff) to flash the ape. "Oh, yes, Koko, Nancy has nipples. Nancy can show you her nipples," Patterson reportedly said on one occasion. And on another: "Koko, you see my nipples all the time. You are probably bored with my nipples. You need to see new nipples. I will turn my back so Kendra can show you her nipples."<ref>{{Cite web |date=June 21, 2018 |title=The Real Meaning of Koko's Purported Nipple Fetish |url=https://slate.com/technology/2018/06/koko-the-ape-obituaries-are-overlooking-her-nipple-fetish-and-other-important-things.html |access-date=June 13, 2022 |website=slate.com}}</ref> Shortly thereafter, a third woman filed suit, alleging that upon being first introduced to Koko, Patterson told her that Koko was communicating that she wanted to see the woman's nipples, pressuring her to submit to Koko's demands and informing her that "everyone does it for her around here." When the woman briefly lifted her t-shirt, flashing her undergarments, Patterson admonished the woman and reiterated that Koko wanted to see her nipples. When the woman relented and showed her breasts to Koko, Patterson commented "Oh look, Koko, she has big nipples." On another occasion, one of the gorilla's handlers told the woman that Koko wanted to be alone with her. When the woman went to Koko's enclosure, Koko began to squat and breathe heavily.<ref name="Yollin 2018b">{{Cite news |last=Yollin |first=Patricia |date=February 26, 2005 |title=Ex-worker is third to sue over gorilla / Woman says she had to show her breasts to Koko |work=San Francisco Chronicle |url=https://www.sfgate.com/bayarea/article/PENINSULA-Ex-worker-is-third-to-sue-over-2727427.php |access-date=August 16, 2018}}</ref> The lawsuits were [[Settlement (litigation)|settled]] out of court.<ref name="Weiner 2005">{{Cite magazine |last=Weiner |first=Jody |date=July 2005 |title=Hot Koko |url=http://ww2.callawyer.com/clstory.cfm?pubdt=200507&eid=734304&evid=1 |url-status=dead |magazine=California Lawyer |page=80 |archive-url=https://web.archive.org/web/20180816175052/http://ww2.callawyer.com/clstory.cfm?pubdt=200507&eid=734304&evid=1 |archive-date=August 16, 2018 |access-date=August 16, 2018}}</ref><ref name="Weiner 2006">{{Cite book |last=Weiner |first=Jody |title=Kinship with Animals |publisher=Council Oak |year=2006 |isbn=9781571781895 |editor-last=Solisti |editor-first=Kate |location=San Francisco/Tulsa |pages=[https://archive.org/details/kinshipwithanima00mich/page/182 182]–188 |chapter=Hot Koko & the Fetching Cat |editor-last2=Tobias |editor-first2=Michael |chapter-url=https://archive.org/details/kinshipwithanima00mich |chapter-url-access=registration}}</ref><ref name="Yollin 2018a">{{Cite news |last=Yollin |first=Patricia |date=February 18, 2005 |title=Gorilla Foundation rocked by breast display lawsuit / Former employees say they were told to expose chests |work=San Francisco Chronicle |url=https://www.sfgate.com/bayarea/article/SAN-MATEO-COUNTY-Gorilla-Foundation-rocked-by-2729786.php |access-date=August 16, 2018}}</ref><ref name="BBC NEWS 2005">{{Cite news |date=February 20, 2005 |title='Gorilla breast fetish' women sue |work=BBC News |url=http://news.bbc.co.uk/2/hi/americas/4280961.stm |access-date=August 16, 2018}}</ref><ref name="Yollin 2018b" /><ref name="The Age 2005">{{Cite web |last=Agence France-Presse |author-link=Agence France-Presse |date=February 21, 2005 |title=Gorilla with a nipple fetish |url=https://www.theage.com.au/world/gorilla-with-a-nipple-fetish-20050221-gdzmzj.html |access-date=August 16, 2018 |website=The Age}}</ref><ref name="The Inquisitr 2015">{{Cite web |last=D. |first=Shayla |date=October 15, 2015 |title=Koko The Gorilla Celebrates 44th Birthday With Two Cute And Cuddly Gifts |url=https://www.inquisitr.com/2497772/koko-the-gorilla-celebrates-44th-birthday-with-two-cute-and-cuddly-gifts-video/ |access-date=August 16, 2018 |website=The Inquisitr}}</ref>

When asked to comment on the matter, gorilla expert Kristen Lukas<!-- Seems notable --> said that other gorillas are not known to have had a similar nipple fixation.<ref name="Yollin 2018a" /> A former caregiver stated that Patterson would interpret the sign for "nipple" as a sound-alike, "people", when notable donors were present.<ref name=":0" />

==Later life and death==
After Patterson's research with Koko was completed, the gorilla moved to a reserve in Woodside, California. At the reserve, Koko lived with another gorilla, [[Michael (gorilla)|Michael]], but he died in 2000. She then lived with another male gorilla, [[Ndume (gorilla)|Ndume]],<ref name="Hillix2004">{{Cite book |last1=Hillix |first1=William Allen |title=Animal Bodies, Human Minds: Ape, Dolphin, and Parrot Language Skills |last2=Rumbaugh |first2=Duane M. |date=January 2004 |publisher=[[Springer Science+Business Media]] |isbn=978-1-4419-3400-0 |editor-last=Tuttle |editor-first=Russell Howard |editor-link=Russell Tuttle |series=Developments in Primatology: Progress and Prospects |location=New York |pages=99–111 |chapter=Koko Fine Sign Gorilla |type=Print |doi=10.1007/978-1-4757-4512-2 |lccn=2003051306 |oclc=968642386 |s2cid=42284074}}</ref> until her death.

At the preserve, Koko also met and interacted with a variety of celebrities, including [[Robin Williams]], [[Fred Rogers]], [[Betty White]], [[William Shatner]], [[Flea (musician)|Flea]], [[Leonardo DiCaprio]], [[Peter Gabriel]], and [[Sting (musician)|Sting]].<ref name="FamousFans">{{Cite news |last=Bender |first=Kelli |date=June 21, 2018 |title=Robin Williams, Mister Rodgers, Leonardo DiCaprio and 5 More of Koko the Gorilla's Famous Fans |url=https://people.com/pets/koko-gorilla-robin-williams-celebrity-fans/ |url-status=live |archive-url=https://web.archive.org/web/20180624081122/https://people.com/pets/koko-gorilla-robin-williams-celebrity-fans/ |archive-date=June 24, 2018 |access-date=June 24, 2018 |work=[[People (magazine)|People]] |department=Pets (Zoo Animals) |issn=0093-7673}}</ref>

Koko died in her sleep during the morning of June 19, 2018, at the Gorilla Foundation's preserve in [[Woodside, California]], at the age of 46.<ref name="KokoPassing">{{Cite press release |title=The Gorilla Foundation is sad to announce the passing of our beloved Koko |date=June 20, 2018 |publisher=[[The Gorilla Foundation]] |url=https://www.koko.org/gorilla-foundation-sad-announce-passing-our-beloved-koko |quote=Following the article, the book Koko's Kitten was published and continues to be used in elementary schools worldwide. Her impact has been profound and what she has taught us about the emotional capacity of gorillas and their cognitive abilities will continue to shape the world. |access-date=June 24, 2018 |url-status=dead |archive-url=https://web.archive.org/web/20180624085628/https://www.koko.org/gorilla-foundation-sad-announce-passing-our-beloved-koko |archive-date=June 24, 2018 |author=<!--None listed.--> |type=Press release}}</ref><ref name="KokoDiesNYT">{{Cite news |last=Chokshi |first=Niraj |date=June 21, 2018 |title=Koko the Gorilla, Who Used Sign Language and Befriended Mr. Rogers, Dies at 46 |work=[[New York Times]] |department=U.S. |url=https://www.nytimes.com/2018/06/21/us/koko-gorilla-death-sign-language.html |url-status=live |access-date=June 24, 2018 |archive-url=https://archive.today/20180624073449/https://www.nytimes.com/2018/06/21/us/koko-gorilla-death-sign-language.html |archive-date=June 24, 2018 |issn=0362-4331 |eissn=1553-8095}}</ref> The Gorilla Foundation released a statement that "The impact has been profound and what she has taught us about the emotional capacity of gorillas and their cognitive abilities will continue to shape the world."<ref name="KokoPassing" /><ref name="RedrewTheLines">{{Cite news |last=Chappell |first=Bill |date=June 21, 2018 |title=Koko The Gorilla Dies; Redrew The Lines Of Animal-Human Communication |publisher=[[NPR]] |department=Remembrances |url=https://www.npr.org/2018/06/21/622160278/koko-the-gorilla-dies-redrew-the-lines-of-animal-human-communication |url-status=live |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20180624090255/https://www.npr.org/2018/06/21/622160278/koko-the-gorilla-dies-redrew-the-lines-of-animal-human-communication |archive-date=June 24, 2018}}</ref> Despite her comparatively old age, her death took staff members of the Gorilla Foundation by surprise.<ref>{{Cite news |last=Mcclatchy |first=Ap |date=June 22, 2018 |title=Koko, the gorilla whose sign language abilities changed our view of animal intelligence, dies at 46 |work=[[Twin Cities Pioneer Press]] |department=News (National & World) |url=https://www.twincities.com/2018/06/22/koko-the-gorilla-whose-sign-language-abilities-changed-our-view-of-animal-intelligence-dies-at-46-2/ |url-status=live |access-date=June 24, 2018 |archive-url=https://web.archive.org/web/20180624090900/https://www.twincities.com/2018/06/22/koko-the-gorilla-whose-sign-language-abilities-changed-our-view-of-animal-intelligence-dies-at-46-2/ |archive-date=June 24, 2018 |issn=0892-1083 |quote=Joy Chesbrough, the foundation's chief development officer, told ''The Times'' that Koko 'went peacefully' and that, despite her advanced age, her death was unexpected. Staff members were taking the loss hard, Chesbrough said.}}</ref> Ndume was transferred to the [[Cincinnati Zoo and Botanical Garden|Cincinnati Zoo]] after a lengthy legal battle.<ref>{{Cite web |last=Staff |first=WLWT Digital |date=June 14, 2019 |title=Silverback gorilla Ndume arrives at Cincinnati Zoo after months-long court battle |url=https://www.wlwt.com/article/silverback-gorilla-ndume-arrives-at-cincinnati-zoo-after-months-long-court-battle/28034245 |access-date=December 11, 2023 |website=WLWT |language=en}}</ref>

==In popular culture==
{{trivia|date=October 2023}}
{{multiple image
| direction = vertical
| width     = 150
| footer    =
| image1    =
| alt1      =
| caption1  =
| image2    =
| alt2      =
| caption2  =
}}

===Books and documentaries===
* 1978 ''[[Koko: A Talking Gorilla]]'', a documentary film by [[Barbet Schroeder]]
* 1978 cover of ''[[National Geographic]]'' magazine that Koko photographed, as well as feature article
* 1981 ''The Education of Koko'', a book by Patterson and naturalist [[Eugene Linden (author)|Eugene Linden]] ({{ISBN|0030461014}})
* 1985 ''Koko's Kitten'', a picture book by Patterson and photographer Ronald Cohn ({{ISBN|0590444255}})
* 1986 ''Silent Partners: The Legacy of the Ape Language Experiments'', a book by [[Eugene Linden (author)|Eugene Linden]] ({{ISBN|0345342348}})
* 1987 ''Koko's Story'', a children's book by Patterson for [[Scholastic Corporation]] ({{ISBN|0590413643}})
* 1990 ''Koko's Kitten'', a 15-minute re-enactment of the story of the gorilla's adoption of a kitten, featured in the ''[[Public Broadcasting Services|PBS]]'' children's show ''[[Reading Rainbow]]''<ref>{{Cite web |title=Koko's Kitten |url=https://www.koko.org/kokos-kitten |access-date=June 21, 2018 |publisher=[[The Gorilla Foundation]] |archive-date=June 19, 2014 |archive-url=https://web.archive.org/web/20140619165058/https://www.koko.org/kokos-kitten |url-status=dead }}</ref>
* 1999 ''A Conversation with Koko'', a [[PBS]] documentary for ''[[Nature (TV series)|Nature]]'', narrated by [[Martin Sheen]]<ref>{{Cite web |date=August 8, 1999 |title=A Conversation with Koko |url=http://www.pbs.org/wnet/nature/conversation-koko/12392/ |publisher=[[PBS]]}}</ref>
* 1999 ''The Parrot's Lament'', by [[Eugene Linden (author)|Eugene Linden]] ({{ISBN|0525944761}})
* 2000 ''Koko-Love!'', a picture book by Patterson and photographer Ronald Cohn ({{ISBN|0525463194}})
* 2001 ''Koko and Robin Williams'', a short featurette on [[Robin Williams]] meeting Koko<ref>{{Citation |last=Jan Turner |title=Koko the Gorilla with Robin Williams.mp4 |date=July 2, 2012 |url=https://www.youtube.com/watch?v=GorgFtCqPEs |archive-url=https://ghostarchive.org/varchive/youtube/20211111/GorgFtCqPEs |access-date=April 29, 2017 |archive-date=November 11, 2021 |url-status=live}}{{cbignore}}</ref>
* 2008 ''Little Beauty'', a picture book by [[Anthony Browne (author)|Anthony Browne]] inspired by Koko's adoption of a pet kitten ({{ISBN|0763649678}})
* 2016 ''Koko: The Gorilla Who Talks to People'', a [[BBC]] documentary also shown on [[PBS]]<ref>{{Cite web |title=Koko: The Gorilla Who Talks to People – BBC One |url=https://www.bbc.co.uk/programmes/b07gxpd7 |website=BBC}}</ref><ref>{{Cite web |title=Koko – The Gorilla Who Talks &#124; PBS |url=https://www.pbs.org/show/koko-gorilla-who-talks/ |via=www.pbs.org}}</ref>
* 2019 ''A Wish for Koko'', a children's book in honor of Koko's life<ref>{{Cite web |title=A Wish for Koko |url=https://www.koko.org/childrens-book-a-wish-for-koko/ |website=[[The Gorilla Foundation]]}}</ref>
* 2019 ''Koko the Gorilla'', The Musers commentary on Koko's life<ref>{{Cite web |last=<!--Not stated--> |date=October 13, 2020 |title=Koko the gorilla |url=https://www.theunticket.com/koko-the-gorilla-friendboat-with-muser-10-6-20/}}</ref>

===Movies and television shows===
* 1998 ''[[Seinfeld]]'', Season 9, Episode 19 (The Maid); [[George Costanza|George]] is nicknamed "Koko the monkey" after co-workers witness him yelling and flailing his arms with a banana in his hand
* 1998 ''[[Mr Rogers' Neighborhood]]'', Episode 1727 (You and I Together); [[Mister Rogers]] visits with Koko who has learned how to communicate in sign language
* 2009 ''[[The Big Bang Theory]]'', Season 3, Episode 10 (The Gorilla Experiment); [[Sheldon Cooper|Sheldon]] makes an attempt to teach physics to [[Penny (The Big Bang Theory)|Penny]], like when Koko learned Sign Language.

==See also==
* [[Great ape language]]
* [[Primate cognition]]
* [[List of individual apes]]

==References==
{{Reflist}}

==Further reading==
{{See also|Animal language#Further reading}}
* Hahn, Emily (1988). ''Eve and the Apes.'' New York: Weidenfeld & Nicolson. {{ISBN|1-555-84172-4}}.
* {{Cite book |last1=Patterson |first1=F.G.P. |title=All Apes Great and Small: African Apes |last2=M. L. Matevia |publisher=Springer |year=2001 |isbn=0306467577 |editor-last=Biruté M.F. Galdikas |pages=165–76 |chapter=Twenty-seven Years of Project Koko and Michael |author-link=Francine Patterson |editor-last2=Nancy Erickson Briggs |editor-last3=Lori K. Sheeran |editor-last4=Gary L. Shapiro |editor-last5=Jane Goodall}}
* Patterson, Francine and Eugene Linden (1981). ''The Education of Koko''. New York: Holt, Rineholt and Winston. {{ISBN|0-03-046101-4}}
* Patterson, Francine and Wendy Gordon (1993). [http://www.animal-rights-library.com/texts-m/patterson01.htm "The case for the personhood of gorillas"] In: P Cavalieri and P Singer (Eds) ''The Great Ape Project: Equality Beyond Humanity'', St. Martin's Press, pp.&nbsp;58–77. {{ISBN|978-0312118181}}.
* {{Cite magazine |last=Vessels |first=Jane |date=January 1985 |title=Koko's Kitten |magazine=[[National Geographic (magazine)|National Geographic]] |volume=167 |issue=1 |pages=110–13 |issn=0027-9358 |oclc=643483454}}
* Weiner, Jody (2006). "Hot Koko & the Fetching Cat". ''Kinship with Animals''. Updated Edition Ed. Kate Solisti and Michael Tobias. San Francisco/Tulsa: Council Oak. pp.&nbsp;182–88. {{ISBN|978-1571781895}}

==External links==
* {{Official website}}
* {{IMDb name|id=nm1162401|name=Koko}}

{{Notable apes|state=expanded}}
{{Great ape language}}
{{Apes}}
{{Portal bar|Primates|Mammals|Animals|California|United States}}
{{Authority control}}

{{DEFAULTSORT:Koko (Gorilla)}}
[[Category:1971 animal births]]
[[Category:2018 animal deaths]]
[[Category:Culture in the San Francisco Bay Area]]
[[Category:Female mammals]]
[[Category:History of the San Francisco Bay Area]]
[[Category:Individual apes involved in language studies]]
[[Category:Individual gorillas]]
[[Category:Individual primates in the United States]]