Behavioral Ecology and Sociobiology

, Volume 63, Issue 9, pp 1331–1344 | Cite as

“Friendships” between new mothers and adult males: adaptive benefits and determinants in wild baboons (Papio cynocephalus)

  • Nga Nguyen
  • Russell C. Van Horn
  • Susan C. Alberts
  • Jeanne Altmann
Original Paper

Abstract

Close associations between adult males and lactating females and their dependent infants are not commonly described in non-monogamous mammals. However, such associations [sometimes called “friendships” (Smuts 1985)] are regularly observed in several primate species in which females mate with multiple males during the fertile period. The absence of mating exclusivity among “friends” suggests that males should invest little in infant care, raising questions about the adaptive significance of friendship bonds. Using data from genetic paternity analyses, patterns of behavior, and long-term demographic and reproductive records, we evaluated the extent to which friendships in four multi-male, multi-female yellow baboon (Papio cynocephalus) groups in Amboseli, Kenya represent joint parental care of offspring or male mating effort. We found evidence that mothers and infants benefited directly from friendships; friendships provided mother–infant dyads protection from harassment from other adult and immature females. In addition, nearly half of all male friends were the genetic fathers of offspring and had been observed mating with mothers during the days of most likely conception for those offspring. In contrast, nearly all friends who were not fathers were also not observed to consort with the mother during the days of most likely conception, suggesting that friendships between mothers and non-fathers did not result from paternity confusion. Finally, we found no evidence that prior friendship increased a male’s chances of mating with a female in future reproductive cycles. Our results suggest that, for many male–female pairs at Amboseli, friendships represented a form of biparental care of offspring. Males in the remaining friendship dyads may be trading protection of infants in exchange for some resources or services not yet identified. Our study is the first to find evidence that female primates gain social benefits from their early associations with adult males.

Keywords

Male–female associations Parental care Mating effort Infant harassment 

Supplementary material

265_2009_786_MOESM1_ESM.doc (82 kb)
ESM Table S1Identifying male friends from grooming and proximity data. Comparison of the identities of females’ most frequent male grooming and proximity partner(s) over the perinatal period for the 29 focal mothers. In cases where females spent equal amounts of time in proximity to each of two males, the names of both males are given. Females were seen in proximity to, but never grooming with, any adult males in four cases. Data are sorted by whether mothers’ grooming partner was the same individual as her proximity partner (Y) or not (N). (DOC 81 kb)
265_2009_786_MOESM2_ESM.doc (157 kb)
ESM Table S2The characteristics of friendship bonds. The 29 mother–infant dyads included mothers and infants of all backgrounds. Male friends consisted of 16 of the 34 adult males resident in the four multi-male groups during the study period. (DOC 255 kb)
265_2009_786_MOESM3_ESM.doc (14 kb)
ESM Table S3Comparison of prior mating success with mothers between friends who were fathers (Y) and friends who were not fathers (N). Females who consorted with males for less than 5 h during the fertile phase of the cycle in which the focal infant was conceived (indicated by gray highlighting) were not included in subsequent analyses. (DOC 13 kb)
265_2009_786_MOESM4_ESM.doc (81 kb)
ESM Table S4Comparisons of fathers who were friends (Y) with fathers who were not friends (N) for the 23 mother–infant dyads for whom paternity could be assigned. (DOC 81 kb)
265_2009_786_MOESM5_ESM.doc (24 kb)
ESM Table S5Comparisons of fathers who were friends with fathers who were not friends, using independent samples t tests. (DOC 45.0 kb)
265_2009_786_MOESM6_ESM.doc (16 kb)
ESM Table S6Male mating success of former friends in future reproductive cycles. For male friends who were resident in the group on only a fraction of the days after their former friend resumed cycling, mating success was computed only from the period in which both friends were resident in the group together. Data are sorted by the proportion of months in which both friends were resident in the group after the focal female resumed cycling. (DOC 28.5 kb)

References

  1. Alberts SC (1999) Paternal kin discrimination in wild baboons. Proc R Soc Lond B Biol Sci 266:1501–1506Google Scholar
  2. Alberts SC, Altmann J (1995) Preparation and activation—determinants of age at reproductive maturity in male baboons. Behav Ecol Sociobiol 36:397–406Google Scholar
  3. Alberts SC, Altmann J (2003) Matrix models for primate life history analysis. In: Kappeler P, Pereira ME (eds) Primate life history and socioecology. University of Chicago Press, Chicago, pp 66–102Google Scholar
  4. Alberts SC, Buchan JC, Altmann J (2006) Sexual selection in wild baboons: from mating opportunities to paternity success. Anim Behav 72:1177–1196Google Scholar
  5. Alberts SC, Sapolsky RM, Altmann J (1992) Behavioral, endocrine, and immunological correlates of immigration by an aggressive male into a natural primate group. Horm Behav 26:167–178PubMedGoogle Scholar
  6. Alberts SC, Watts HE, Altmann J (2003) Queuing and queue-jumping: long-term patterns of reproductive skew in male savannah baboons, Papio cynocephalus. Anim Behav 65:821–840Google Scholar
  7. Altmann J (1974) Observational study of behavior: sampling methods. Behaviour 49:227–267PubMedGoogle Scholar
  8. Altmann J (1980) Baboon mothers and infants. Harvard University Press, CambridgeGoogle Scholar
  9. Altmann J, Alberts SC (2003) Intraspecific variability in fertility and offspring survival in a nonhuman primate: behavioral control of ecological and social sources. In: Wachter KW, Bulatao RA (eds) Offspring: the biodemography of fertility and family behavior. National Academy Press, Washington, DC, pp 140–169Google Scholar
  10. Altmann SA (1998) Foraging for survival: yearling baboons in Africa. University of Chicago Press, ChicagoGoogle Scholar
  11. Anderson CM (1983) Levels of social organization and male female bonding in the genus Papio. Am J Phys Anthropol 60:15–22PubMedGoogle Scholar
  12. Armstrong DP (1991) Aggressive of breeding territorial honeyeaters corresponds to seasonal changes in nectar availability. Behav Ecol Sociobiol 29:103–111Google Scholar
  13. Aureli F, de Waal FBM (2000) Why natural conflict resolution? In: Aureli F, de Waal FBM (eds) Natural conflict resolution. University of California Press, Berkeley, pp 3–10Google Scholar
  14. Bales KB (1980) Cumulative scaling of paternalistic behavior in primates. Am Nat 116:454–461Google Scholar
  15. Barrett L, Henzi SP, Weingrill T, Lycett JE, Hill RA (1999) Market forces predict grooming reciprocity in female baboons. Proc R Soc Lond B Biol Sci 266:665–670Google Scholar
  16. Beehner JC, Bergman TJ, Cheney DL, Seyfarth RM, Whitten PL (2005) The effect of new alpha males on female stress in free-ranging baboons. Anim Behav 69:1211–1221Google Scholar
  17. Bercovitch FB (1987) Reproductive success in male savanna baboons. Behav Ecol Sociobiol 21:163–72Google Scholar
  18. Bercovitch FB (1991) Mate selection, consortship formation, and reproductive tactics in adult female savanna baboons. Primates 32:437–452Google Scholar
  19. Berenstain L, Wade TD (1983) Intrasexual selection and male mating strategies in baboons and macaques. Int J Primatol 4:201–235Google Scholar
  20. Blumstein DT (2000) The evolution of infanticide in rodents: A comparative analysis. In: van Schaik CP, Janson C (eds) Infanticide by males and its implications. Cambridge University Press, Cambridge, pp 178–197Google Scholar
  21. Borries C, Launhardt K, Epplen C, Epplen JT, Winkler P (1999a) DNA analyses support the hypothesis that infanticide is adaptive in langur monkeys. Proc R Soc Lond B Biol Sci 266:901–904Google Scholar
  22. Borries C, Launhardt K, Epplen C, Epplen JT, Winkler P (1999b) Males as infant protectors in Hanuman langurs (Presbytis entellus) living in multimale groups - defence pattern, paternity and sexual behaviour. Behav Ecol Sociobiol 46:350–356Google Scholar
  23. Buchan JC, Alberts SC, Silk JB, Altmann J (2003) True paternal care in a multi-male primate society. Nature 425:179–181PubMedGoogle Scholar
  24. Bulger JB (1993) Dominance rank and access to estrous females in male savanna baboons. Behaviour 127:67–103Google Scholar
  25. Buss DM (1994) The evolution of desire. Harper Collins, New YorkGoogle Scholar
  26. Chapais B (1983a) Reproductive activity in relation to male dominance and the likelihood of ovulation in rhesus monkeys. Behav Ecol Sociobiol 12:215–228Google Scholar
  27. Chapais B (1983b) Structure of the birth season relationship among adult male and female rhesus monkeys. In: Hinde RA (ed) Primate social relationships. Blackwell Scientific, Oxford, pp 200–208Google Scholar
  28. Chapais B (1986a) Why do adult male and female rhesus monkeys affiliate during the birth season? In: Rawlins RG, Kessler MJ (eds) The Cayo Santiago macaques: history, behavior, and biology. State University of New York Press, Albany, pp 173–200Google Scholar
  29. Chapais B (1986b) Why do adult male and female rhesus monkeys affiliate during the birth season? In: Rawlins RG, Kessler MJ (eds) The Cayo Santiago macaques. SUNY Press, Albany, pp 173–200Google Scholar
  30. Charpentier MJE, Van Horn RC, Altmann J, Alberts SC (2008) Paternal effects on offspring fitness in a multimale primate society. Proc Natl Acad Sci U S A 105:1988–1992PubMedGoogle Scholar
  31. Cheney DL, Seyfarth RM, Fischer J, Beehner J, Bergman T, Johnson SE, Kitchen DM, Palombit RA, Rendall D, Silk JB (2004) Factors affecting reproduction and mortality among baboons in the Okavango Delta, Botswana. Int J Primatol 25:401–428Google Scholar
  32. Chuang-Dobbs HC, Webster MS, Holmes RT (2001) Paternity and parental care in the black-throated blue warbler, Dendroica caerulescens. Anim Behav 62:83–92Google Scholar
  33. Clutton-Brock TH (1989) Mammalian mating systems. Proc R Soc Lond B Biol Sci 236:339–372PubMedGoogle Scholar
  34. Clutton-Brock TH (1991) The evolution of parental care. Princeton University Press, PrincetonGoogle Scholar
  35. Dixon A, Ross D, Omalley SLC, Burke T (1994) Paternal investment inversely related to degree of extra pair paternity in the reed bunting. Nature 371:698–700Google Scholar
  36. Drickamer LC, Gowaty PA, Holmes CM (2000) Free female mate choice in house mice affects reproductive success and offspring viability and performance. Anim Behav 59:371–378PubMedGoogle Scholar
  37. Dunbar RIM (1991) Functional significance of social grooming in primates. Folia Primatol 57:121–131Google Scholar
  38. Estes RD (1992) The behavior guide to african mammals: including hoofed mammals, carnivores. University of California Press, Berkeley, PrimatesGoogle Scholar
  39. Eggert AK, Muller JK (1997) Biparental care and social evolution in burying beetles: lessons from the larder. In: Choe JC, Crespi BJ (eds) The evolution of social behavior in insects and arachnids. Cambridge University Press, Cambridge, pp 216–236Google Scholar
  40. Freeman-Gallant CR (1997) Parentage and paternal care: consequences of intersexual selection in Savannah sparrows? Behav Ecol Sociobiol 40:395–400Google Scholar
  41. Gerald CN (1995) Demography of the Virunga mountain gorilla (Gorilla gorilla beringei). MSc thesis. Princeton University, PrincetonGoogle Scholar
  42. Gori DF, Rohwer S, Caselle J (1996) Accepting unrelated broods helps replacement male yellow-headed blackbirds attract mates. Behav Ecol 7:49–54Google Scholar
  43. Gubernick DJ (1994) Biparental care and male-female relations in mammals. In: Parmigiani S, von Saal FS (eds) Infanticide and parental care. Harwood, Chur, Switzerland, pp 427–463Google Scholar
  44. Harcourt AH (1979) Social relationships between adult male and female mountain gorillas in the wild. Anim Behav 27:325–342Google Scholar
  45. Hausfater G (1975) Dominance and reproduction in baboons (Papio cynocephalus). Karger, BaselGoogle Scholar
  46. Hausfater G, Altmann J, Altmann S (1982) Long-term consistency of dominance relations among female baboons (Papio cynocephalus). Science 217:752–755PubMedGoogle Scholar
  47. Hausfater G, Hrdy SB (1984) Infanticide: comparative and evolutionary perspectives. Aldine de Gruyter, New YorkGoogle Scholar
  48. Hendrickx AG, Kraemer DC (1969) Observations on the menstrual cycle, optimal mating time and pre-implantation embryos in the baboon, Papio anubis and Papio cynocephalus. J Reprod Fertil Supp 6:119–128Google Scholar
  49. Hill DA (1990) Social relationships between adult male and female rhesus macaques.2. Nonsexual affiliative behavior. Primates 31:33–50Google Scholar
  50. Hill K, Boesch C, Goodall J, Pusey A, Williams J, Wrangham R (2001) Mortality rates among wild chimpanzees. J Hum Evol 40:437–450PubMedGoogle Scholar
  51. Hiraiwa M (1981) Maternal and alloparental care in a troop of free-ranging Japanese monkeys. Primates 22:309–329Google Scholar
  52. Hrdy SB (1979) Infanticide among animals - Review, classification, and examination of the implications for the reproductive strategies of females. Ethol Sociobiol 1:13–40Google Scholar
  53. Keddy-Hector AC, Seyfarth RM, Raleigh MJ (1989) Male parental care, female choice and the effect of an audience in vervet monkeys. Anim Behav 38:262–271Google Scholar
  54. Keverne EB, Martensz ND, Tuite B (1989) Beta endorphin concentrations in cerebrospinal-fluid of monkeys are influenced by grooming relationships. Psychoneuroendocrinology 14:155–161PubMedGoogle Scholar
  55. Kingdon J (2003) The Kingdon field guide to african mammals. Black, LondonGoogle Scholar
  56. Kleiman DG, Malcolm JR (1981) The evolution of male parental investment in mammals. In: Gubernick DJ, Klopfer PH (eds) Parental care in mammals. Plenum, New York, pp 347–387Google Scholar
  57. Kleindorfer S, Wasser SK (2004) Infant handling and mortality in yellow baboons (Papio cynocephalus): evidence for female reproductive competition? Behav Ecol Sociobiol 56:328–337Google Scholar
  58. Lack DL (1968) Ecological adaptations for breeding in birds. Methuen, LondonGoogle Scholar
  59. Lemasson A, Palombit RA, Jubin R (2008) Friendships between males and lactating females in a free-ranging group of olive baboons (Papio hamadryas anubis): evidence from playback experiments. Behav Ecol Sociobiol 62:1027–1035Google Scholar
  60. Maestripieri D (2000) Determinants of affiliative interactions between adult males and lactating females in pigtail macaques (Macaca nemestrina nemestrina). Ethology 106:425–439Google Scholar
  61. Manson JH (1994) Mating patterns, mate choice, and birth season heterosexual relationships in free-ranging rhesus macaques. Primates 35:417–433Google Scholar
  62. Marshall TC, Slate J, Kruuk LEB, Pemberton JM (1998) Statistical confidence for likelihood-based paternity inference in natural populations. Mol Ecol 7:639–655PubMedGoogle Scholar
  63. Mason JH (1994) Mating patterns, mate choice, and birth season heterosexual relationships in free-ranging rhesus macaques. Primates 35:417–433Google Scholar
  64. Menard N, von Segesser F, Scheffrahn W, Pastorini J, Vallet D, Gaci B, Martin RD, Gautier-Hion A (2001) Is male-infant caretaking related to paternity and/or mating activities in wild Barbary macaques (Macaca sylvanus)? C R Acad Sci SeÂr 3 Sci Vie 324:601–610Google Scholar
  65. Moller AP, Birkhead TR (1993) Certainty of paternity covaries with paternal care in birds. Behav Ecol Sociobiol 33:261–268Google Scholar
  66. Morris D (1967) The naked ape. Cape, LondonGoogle Scholar
  67. Nicolson NA (1987) Infants, mothers, and other females. In: Smuts B, Cheney DL, Seyfarth RM, Wrangham RW, Struhsaker TT (eds) Primate societies. Unversity of Chicago Press, Chicago, pp 330–342Google Scholar
  68. Noe R, Sluijter AA (1990) Reproductive tactics of male savanna baboons. Behaviour 113:117–170Google Scholar
  69. Overdorff DJ (1998) Are Eulemur species pair-bonded? Social organization and mating strategies in Eulemur fulvus rufus from 1988–1995 in southeast Madagascar. Am J Phys Anthropol 105:153–166PubMedGoogle Scholar
  70. Palombit RA (2000) Infanticide and the evolution of male–female bonds in animals. In: van Schaik CP, Janson C (eds) Infanticide by males and its implications. Cambridge University Press, Cambridge, pp 239–268Google Scholar
  71. Palombit RA, Seyfarth RM, Cheney DL (1997) The adaptive value of ‘friendships’ to female baboons: experimental and observational evidence. Anim Behav 54:599–614PubMedGoogle Scholar
  72. Parmigiani S, Palanza P, Mainardi D, Brain PF (1994) Infanticide and protection of young in house mice (Mus domesticus): female and male strategies. In: Parmigiani S, von Saal FS (eds) Infanticide and parental care. Harwood, Chur, Switzerland, pp 341–363Google Scholar
  73. Paul A (1999) The socioecology of infant handling in primates: is the current model convincing? Primates 40:33–46Google Scholar
  74. Paul A, Kuester J, Arnemann J (1996) The sociobiology of male-infant interactions in Barbary macaques, Macaca sylvanus. Anim Behav 51:155–170Google Scholar
  75. Price EC (1990) Infant carrying as a courtship strategy of breeding male cotton-top tamarins. Anim Behav 40:784–786Google Scholar
  76. Pusey AE, Packer C (1987) Dispersal and philopatry. In: Smuts B, Cheney DL, Seyfarth RM, Wrangham RW, Struhsaker TT (eds) Primate societies. University of Chicago Press, Chicago, pp 250–266Google Scholar
  77. Pusey AE, Packer C (1994) Infanticide in lions: consequences and counterstrategies. In: Parmigiani S, von Saal FS (eds) Infanticide and parental care. Harwood, London, pp 277–299Google Scholar
  78. Ransom TW, Ransom BS (1971) Adult male–infant relations among baboons (Papio anubis). Folia Primatol 16:179–195PubMedGoogle Scholar
  79. Rios-Cardenas O, Webster AS (2005) Paternity and paternal effort in the pumpkinseed sunfish. Behav Ecol 16:914–921Google Scholar
  80. Rowell TE, Olson DK (1983) Alternative mechanisms of social organization in monkeys. Behaviour 86:31–54Google Scholar
  81. Sandvik M, Rosenqvist G, Berglund A (2000) Male and female mate choice affects offspring quality in a sex-role-reversed pipefish. Proc R Soc Lond B Biol Sci 267:2151–2155Google Scholar
  82. Sapolsky RM (1993) Neuroendocrinology of the stress response. In: Becker JB, Breedlove SM, Crews D (eds) Behav Endocrinol. MIT Press, Cambridge, pp 287–324Google Scholar
  83. Seyfarth RM (1978a) Social relationships among adult male and female baboons. I. Behaviour during sexual consortship. Behaviour 64:204–226Google Scholar
  84. Seyfarth RM (1978b) Social relationships among adult male and female baboons. II. Behavior throughout the female reproductive cycle. Behaviour 64:227–247Google Scholar
  85. Seyfarth RM (1983) Grooming and social competition in primates. In: Hinde RA (ed) Primate Social relationships: an integrated approach. Blackwell, London, pp 182–189Google Scholar
  86. Shaikh AA, Celaya CL, Gomez I, Shaikh SA (1982) Temporal relationship of hormonal peaks to ovulation and sex skin deturgescence in the baboon. Primates 23:444–452Google Scholar
  87. Shopland JM, Altmann J (1987) Fatal intragroup kidnapping in yellow baboons. Am J Primatol 13:61–65Google Scholar
  88. Sicotte P (1994) Effect of male competition on male female relationships in bi male groups of mountain gorillas. Ethology 97:47–64CrossRefGoogle Scholar
  89. Silk JB (1980) Kidnapping and female competition in captive bonnet macaques. Primates 21:100–110Google Scholar
  90. Silk JB (1999) Why are infants so attractive to others? The form and function of infant handling in bonnet macaques. Anim Behav 57:1021–1032PubMedGoogle Scholar
  91. Smith K, Alberts SC, Altmann J (2003) Wild female baboons bias their social behaviour towards paternal half-sisters. Proc R Soc Lond B Biol Sci 270:503–510Google Scholar
  92. Smuts B (1985) Sex and friendship in baboons. Cambridge University Press, CambridgeGoogle Scholar
  93. Smuts B, Gubernick DJ (1992) Male–infant relationships in nonhuman primates: paternal investment or mating effort? In: Hewlett BS (ed) Father–child relations. Aldine de Guyter, New York, pp 1–30Google Scholar
  94. Soltis J, Thomsen R, Matsubayashi K, Takenaka O (2000) Infanticide by resident males and female counter-strategies in wild Japanese macaques (Macaca fuscata). Behav Ecol Sociobiol 48:195–202Google Scholar
  95. Takahata Y (1982) Social relations between adult males and females of Japanese monkeys in the Arashiyama B troop. Primates 23:1–23Google Scholar
  96. Tanaka I, Takefushi H (1993) Elimination of external parasites (lice) is the primary function of grooming in free-ranging japanese macaques. Anthropol Sci 101:187–193Google Scholar
  97. Taub DM (1990) The functions of primate paternalism: a cross-species review. In: Feierman JR (ed) Pedophilia: biosocial dimensions. Springer, New York, pp 338–377Google Scholar
  98. Taub DM, Mehlman PT (1991) Primate paternalistic investment: a cross-species view. In: Loy JD, Peters CB (eds) Understanding behavior: what primate studies tell us about human behavior. Oxford, New York, pp 51–89Google Scholar
  99. Van Horn RC, Wahaj SA, Holekamp KE (2004) Role-reversed nepotism among cubs and sires in the spotted hyena (Crocuta crocuta). Ethology 110:413–426Google Scholar
  100. van Schaik CP (2000) Infanticide by male primates: The sexual selection hypothesis revisited. In: van Schaik CP, Janson CH (eds) Infanticide by males and its implications. Cambridge University Press, Cambridge, pp 27–60Google Scholar
  101. van Schaik CP, Janson CH (2000) Infanticide by males and its implications. Cambridge University Press, CambridgeGoogle Scholar
  102. van Schaik CP, Kappeler PM (1997) Infanticide risk and the evolution of male-female association in primates. Proc R Soc Lond B Biolog Sci 264:1687–1694Google Scholar
  103. van Schaik CP, Paul A (1996) Male care in primates: does it ever reflect paternity? Evol Anthropol 5:152–156Google Scholar
  104. Wasser SK, Barash DP (1981) The selfish allomother—a comment. Ethol Sociobiol 2:91–93Google Scholar
  105. Watts DP (1996) Comparative socio-ecology of gorillas. In: McGrew WC, Marchant LF, Nishida T (eds) Great ape societies. Cambridge University Press, Cambridge, pp 16–28Google Scholar
  106. Weatherhead PJ, Montgomerie R, Gibbs HL, Boag PT (1994) The cost of extra-pair fertilizations to female red-winged blackbirds. Proc R Soc Lond B Biol Sci 258:315–320Google Scholar
  107. Widdig A, Nurnberg P, Krawczak M, Streich WJ, Bercovitch FB (2001) Paternal relatedness and age proximity regulate social relationships among adult female rhesus macaques. Proc Natl Acad Sci U S A 98:13769–13773PubMedGoogle Scholar
  108. Wildt DE, Doyle LL, Stone SC, Harrison RM (1977) Correlation of perineal swelling with serum ovarian hormone levels, vaginal cytology, and ovarian follicular development during the baboon reproductive cycle. Primates 18:261–270Google Scholar
  109. Wilson EO (1975) Sociobiology. Belknap, CambridgeGoogle Scholar
  110. Wittenberger JF, Tilson RL (1980) The evolution of monogamy—hypotheses and evidence. Annu Rev Ecol Syst 11:197–232Google Scholar
  111. Wolff JO, Cicirello DM (1991) Comparative paternal and infanticidal behavior of sympatric white-footed mice (Peromyscus leucopus noveboracensis) and deermice (P. maniculatus nubiterrae). Behav Ecol 2:38–45Google Scholar
  112. Wong BBM (2004) Superior fighters make mediocre fathers in the Pacific blue-eye fish. Anim Behav 67:583–590Google Scholar
  113. Wright PC (1995) Demography and life history of free-ranging Propithecus diadema edwardsi in Ranomafana National Park, Madagascar. Int J Primatol 16:835–854Google Scholar

Copyright information

© US Government 2009

Authors and Affiliations

  • Nga Nguyen
    • 1
    • 2
    • 3
  • Russell C. Van Horn
    • 4
  • Susan C. Alberts
    • 5
    • 6
  • Jeanne Altmann
    • 6
    • 7
    • 8
  1. 1.Department of Conservation & ScienceCleveland Metroparks ZooClevelandUSA
  2. 2.Department of BiologyCase Western Reserve UniversityClevelandUSA
  3. 3.Department of AnthropologyCalifornia State University FullertonFullertonUSA
  4. 4.Conservation & Research for Endangered SpeciesZoological Society of San DiegoSan DiegoUSA
  5. 5.Department of BiologyDuke UniversityDurhamUSA
  6. 6.Institute for Primate ResearchNational Museums of KenyaNairobiKenya
  7. 7.Department of Ecology & Evolutionary BiologyPrinceton UniversityPrincetonUSA
  8. 8.Department of Animal Physiology and Veterinary MedicineUniversity of NairobiNairobiKenya

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