About the First 100 Chimpanzees site

While doing research for her forthcoming book on human relations to captive chimpanzees, Dr. Lori Gruen became interested in the genealogy of chimpanzees in the United States. R. M. Yerkes, a rather elaborate list maker, left behind many incomplete lists that Gruen began filling in while working through archival materials. One document in particular captured her attention -- “Complete List of Chimpanzees: Yale Laboratories of Primate Biology.” The “complete list” contains:

Name | No. | Sex | Birth | Ancestry | Location | Remarks

The “complete list” begins with (1) Bill and ends with (100) Flora. Flora was born the year Yerkes retired as the director of the YLPB, in 1941. It somehow seems fitting that the “complete list” was a tidy 100 as Yerkes retired.

But the “complete list”, wasn’t exactly complete. The males in the colony are all listed with odd-numbers, the females with even numbers. (As an extra measure to maintain sex classifications, the female names all end in vowels, the male names all end in consonants). In 1941, there were more females in the colony than males, and thus while Flora completed the list at 100, 14 names were not yet on the list (they hadn’t been born) and 46 had not yet died. To commemorate the first 100 chimpanzees, Gruen sought to complete the list as best she could.

The details of each of the first 100 chimpanzee’s lives and deaths are based on the best interpretation of the records that have been archived and also on published material that reference individual chimps. The information presented here is only as accurate as the records that were kept. Some of the records conflict (see, for example, Pan and Lita/Lia). When the directorship of the YLPB changed, record keeping also changed. Getting complete and accurate information is also made difficult because some of the records have not yet been made available from the laboratory at the Yerkes Regional Primate Center.

Most of the information presented on each chimp’s page comes from archival records, however, some information is from the published works cited here:

Bill: Robert M. Yerkes, Chimpanzees: A Laboratory Colony (New Haven, CT: Yale University Press, 1943) hereafter Chimpanzees.

Pan: Chimpanzees; R.M. Yerkes “A Chimpanzee Family” Pedagogical Seminary and Journal of Genetic Psychology, 48 (1936): 362-370. (*While the archival records at Yale and at Emory have hand written documentation of Pan being sent to the Navy in Johnsville in 1952 and the annual report confirms that 3 chimps were sent there during that year, a presentation in 1963 to the National Academy of Sciences by Walter R. Miles reports that Miles saw Pan helping Wendy remove a irritant from her eye in 1954. The annual report from 1954 indicates that a “Walker” Miles was a visitor to Orange Park that year. Perhaps the chimp Miles saw was not Pan or perhaps Pan did not die in an acceleration experiment in 1952).

Wendy: Chimpanzees; R.M. Yerkes & M.I. Tomilin, “Mother-Infant Relations in Chimpanzee” Journal of Comparative Psychology, 20 (1938): 321-359; R.Yerkes Blanshard, “Home Life with Chimpanzees – Part 2” in G.H. Bourne (ed.) Progress in Ape Research (New York: Academic Press, Inc., 1977); H. Nissen, “The Ape Colony in Florida” Animal Kingdom, New York Zoological Society, 157 (1944); E. Davis, “Emory’s apes and Monkeys at Home”, The Emory Magazine, September 1965.

Bokar: A.J. Riopelle and C.M. Rogers, “Age Changes in Chimpanzees” in A. Schrier, H. Harlow, & F. Stollnitz (eds.) Behavior of Non Human Primates V. 2 (New York, Academic Press, Inc., 1965).

Nana: R.M. Yerkes “A Chimpanzee Family” Pedagogical Seminary and Journal of Genetic Psychology, 48 (1936): 362-370.

Moos: Chimpanzees

Jim: M. I. Tomilin, “Death of the Oldest Chimpanzee in Captivity” Science V. 83, #2144 (Jan. 31, 1936): 103-4; R.M. Yerkes, Almost Human (New York: The Century Company, 1925).

Jack: R.M. Yerkes, Almost Human (New York: The Century Company, 1925), R.M. Yerkes & M.I. Tomilin, “Mother-Infant Relations in Chimpanzee” Journal of Comparative Psychology, 20 (1938): 321-359.

Frank: Chimpanzees

Alpha: D. O. Hebb, “Spontaneous Neurosis in Chimpanzees: Theoretical Relations with Clinical and Experimental Phenomena” Psychosomatic Medicine, 9 (1947): 3-19

Josie: Chimpanzees

Mona: R.M. Yerkes, Almost Human (New York: The Century Company, 1925), Chimpanzees

Dick: R.M. Yerkes & M.I. Tomilin, “Mother-Infant Relations in Chimpanzee” Journal of Comparative Psychology, 20 (1938): 321-359.

Dita: Chimpanzee

Hal: Margarete Tigges and Johannes Tigges, “Distribution and morphology of myelinated perikarya and dendrites in the olfactory bulb of primates”, Journal of Neurocytology, 9 #6 (Dec 1980): 825 – 834. R.B. Eckhardt, “The Population Structure and Inbreeding Coefficient in the Yerkes Chimpanzee Colony, “ Human Evolution 3 #3(1988): 141-146.

Lia/Lita: The details here are complicated. In Almost Human, Yerkes mentions (Ada)Lita, the child of Jimmy and Monona, born at the Abreu estate in 1923. Records indicate that “Lia” was a gift from the Abreu estate on July 6, 1932 (estimated birth 1924) and that “Lita” was a gift from the Abreu estate on October 5, 1935, and that “Lita” was the child of Blanca and Jack and was born in 1930. It seems unlikely that Mme. Abreu would have named both chimpanzee infants “Lita”.

Gamma: H. Morris, “Gamma, world’s oldest chimp, is aging well at 58” Atlanta Journal Constitution, March 3, 1991.

Jent: G. Bourne, The Ape People, (New York: Putnam, 1971).

YLPB Page: D. Dewsbury, Monkey Farm (Lewisburg, PA: Bucknell University Press, 2006); D. Haraway, Primate Visions (New York: Routledge, 1989).


Archivists and their assistants at both Manuscripts and Archives, Sterling Library, Yale University and Emory University Archives, Woodruff Library, Emory University provided impressive expertise.

Shayla Silver-Balbus, who provided research assistance with much appreciated support from Howard Hughes Medical Institution Summer Fellow Program at Wesleyan, and Sharisse Kanet for reserach assistance.

Don Dewsbury, Alexa Morris, Stephany Harris, and Klaree Boose also provided information and/or assistance.

We gratefully acknowledge permission to use the images found on this website that originate with the Robert Mearns Yerkes Papers, Manuscript Group 569, Manuscripts and Archives, Yale University Library and the Yerkes Regional Primate Research Center Records, ca 1929-1980, Collection #014 Emory University Archives. Permission to reproduce these images must be obtained from the archives at Yale University and/or the archives at Emory University.

This website was researched and written by Dr. Lori Gruen, Philosophy Department and Feminist, Gender, and Sexuality Studies Program, Wesleyan University. It was designed and produced by Anne Marcotty.

Please do not reproduce the content contained on this site without written permission from Lori Gruen (lgruen@wesleyan.edu).

Any information that might be helpful in the continuing development of this chimpanzee genealogical project is most welcome.

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