How males form coalitions against group rivals and the Pandit/van Schaik coalition model

in Behaviour
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In group living animals, there is pronounced variation in the formation and function of cooperation between males via coalitionary aggression. Pandit, van Schaik and colleagues developed a mathematical model to predict the evolution of different coalition types in group-living male primates, the PvS model. Coalitions are classified into five types dependent on the ranks of the participants and the function of the aggression. The main factor determining the coalition types expected to evolve is contest potential, an estimate of female monopolisability by individual males. We examined the model using groups of Assamese (Macaca assamensis) and Barbary macaques (Macaca sylvanus) to gain a full range of contest potentials. We observed, across groups, 393 coalitions during 3645 h of data collection. We measured contest potential on a species-specific basis dependent on the information males can infer about female reproductive state. By examining coalition formation in different populations and species, but also in the same groups over time, we showed the strengths and weaknesses of the PvS model. We discuss why our results do not fully fit the model’s predictions, including differing costs/benefits of coalition formation, such as delayed benefits via increased status, making rank-changing coalitions viable at mid–low contest potential. Alternative factors not considered by the model include the effect of male social bonds on coalition partner choice and the effect of female mate-choice on coalition target selection. Finally, we suggest possible improvements to the model and provide information on how best to test the current predictions of the PvS model.

How males form coalitions against group rivals and the Pandit/van Schaik coalition model

in Behaviour



AlbertsS.BuchanJ.AltmannJ. (2006). Sexual selection in wild baboons: from mating opportunities to paternity success. — Anim. Behav. 72: 1177-1196.

AltmannJ. (1974). Observational study of behavior: sampling methods. — Behaviour 49: 227-267.

AltmannS.A. (1962). A field study of the sociobiology of the rhesus monkey, Macaca mulatta. — Ann. NY Acad. Sci. 102: 338-435.

BercovitchF.B. (1988). Coalitions, cooperation and reproductive tactics among adult male baboons. — Anim. Behav. 36: 1198-1209.

BerghänelA.OstnerJ.SchröderU.SchülkeO. (2011a). Social bonds predict future cooperation in male Barbary macaques, Macaca sylvanus. — Anim. Behav. 81: 1109-1116.

BerghänelA.OstnerJ.SchülkeO. (2011b). Coalitions destabilize dyadic dominance relationships in male Barbary macaques (Macaca sylvanus). — Behaviour 148: 1257.

BerghänelA.SchülkeO.OstnerJ. (2010). Coalition formation among Barbary macaque males: the influence of scramble competition. — Anim. Behav. 80: 675-682.

BermanC.IonicaC.LiJ. (2007). Supportive and tolerant relationships among male Tibetan macaques at Huangshan, China. — Behaviour 144: 631-661.

BissonnetteA. (2009). Testing a model on coalitions in Barbary macaque males (Macaca sylvanus). — PhD Thesis University of Zurich Zurich.

BissonnetteA.BischofbergerN.van SchaikC. (2011). Mating skew in Barbary macaque males: the role of female mating synchrony, female behavior, and male–male coalitions. — Behav. Ecol. Sociobiol. 65: 167-182. VriesH.van SchaikC.P. (2009a). Coalitions in male Barbary macaques, Macaca sylvanus: strength, success and rules of thumb. — Anim. Behav. 78: 329-335.

BissonnetteA.LangeE.Van SchaikC.P. (2009b). A cardinal measure of competitive ability in Barbary macaque males (Macaca sylvanus). — Ethology 115: 671-681.

BoehmC. (1993). Cooperation and prosocial behaviour. — Am. Anthropol. 95: 455-456.

BoehmC. (1999). Hierarchy in the forest — the evolution of egalitarian behavior. — Harvard University PressCambridge, MA.

BrauchK.HodgesK.EngelhardtA.FuhrmannK.ShawE.HeistermannM. (2008). Sex-specific reproductive behaviours and paternity in free-ranging Barbary macaques (Macaca sylvanus). — Behav. Ecol. Sociobiol. 62: 1453-1466.

BrauchK.PfefferleD.HodgesK.MöhleU.FischerJ.HeistermannM. (2007). Female sexual behavior and sexual swelling size as potential cues for males to discern the female fertile phase in free-ranging Barbary macaques (Macaca sylvanus) of Gibraltar. — Horm. Behav. 52: 375-383.

BroomM.KoenigA.BorriesC. (2009). Variation in dominance hierarchies among group-living animals: modeling stability and the likelihood of coalitions. — Behav. Ecol. 20: 844-855.

ChapaisB. (1995). Alliances as means of competition in primates: evolutionary, developmental and cognitive aspects. — Yb. Phys. Anthropol. 38: 115-136.

Clutton-BrockT.H.ParkerG.A. (1992). Potential reproductive rates and the operation of sexual selection. — Q. Rev. Biol. 67: 437-456.

ConnorR.WhiteheadH. (2005). Alliances II. Rates of encounter during resource utilization: a general model of intrasexual alliance formation in fission–fusion societies. — Anim. Behav. 69: 127-132.

ConnorR.C.HeithausM.R.BarreL.M. (1999). Superalliance of bottlenose dolphins. — Nature 397: 571-572.

de VilliersM.S.RichardsonP.R.K.van JaarsveldA.S. (2003). Patterns of coalition formation and spatial association in a social carnivore, the African wild dog (Lycaon pictus). — J. Zool. 260: 377-389.

de VriesH.StevensJ.VervaeckeH. (2006). Measuring and testing the steepness of dominance hierarchies. — Anim. Behav. 71: 585-592.

de WaalF.B.M.HarcourtA.H. (1992). Coalitions and alliances: a history of ethological research. — In: Coalitions and alliances in humans and other animals ( WaalF.B.M. eds). Oxford University PressOxford p.  1-19.

DuffyK.G.WranghamR.W.SilkJ.B. (2007). Male chimpanzees exchange political support for mating opportunities. — Curr. Biol. 17: R586-R587.

DugatkinL.A. (1998). Breaking up fights between others: a model of intervention behaviour. — Proc. Roy. Soc. Lond. B: Biol. Sci. 265: 433-437.

EngelhardtA.HodgesJ.HeistermannM. (2007). Post-conception mating in wild long-tailed macaques (Macaca fascicularis): characterization, endocrine correlates and functional significance. — Horm. Behav. 51: 3-10.

FürtbauerI.SchülkeO.HeistermannM.OstnerJ. (2010). Reproductive and life history parameters of wild female Assamese macaques (Macaca assamensis). — Int. J. Primatol. 31: 501-517.

FürtbauerI.HeistermannM.SchülkeO.OstnerJ. (2011a). Concealed fertility and extended female sexuality in a non-Human primate (Macaca assamensis). — PLoS ONE 6: e23105.

FürtbauerI.MundryR.HeistermannM.SchülkeO.OstnerJ. (2011b). You mate, I mate: macaque females synchronize sex not cycles. — PLoS ONE 6: e26144.

GilbyI.BrentL.N.WroblewskiE.RudicellR.HahnB.GoodallJ.PuseyA. (2013). Fitness benefits of coalitionary aggression in male chimpanzees. — Behav. Ecol. Sociobiol. 67: 373-381.

GogartenJ.KoenigA. (2013). Reproductive seasonality is a poor predictor of receptive synchrony and male reproductive skew among nonhuman primates. — Behav. Ecol. Sociobiol. 67: 123-134.

GordonT.GustD.BusseC.WilsonM. (1991). Hormones and sexual behavior associated with postconception perineal swelling in the sooty mangabey (Cercocebus torquatus atys). — Int. J. Primatol. 12: 585-597.

GustD. (1994). Alpha-male sooty mangabeys differentiate between females’ fertile and their postconception maximal swellings. — Int. J. Primatol. 15: 289-301.

HeistermannM.ZieglerT.van SchaikC.P.LaunhardtK.WinklerP.HodgesJ.K. (2001). Loss of oestrus, concealed ovulation and paternity confusion in free-ranging Hanuman langurs. — Proc. Roy. Soc. Lond. B: Biol. Sci. 268: 2445-2451.

HeistermannM.BrauchK.MöhleU.PfefferleD.DittamiJ.HodgesK. (2008). Female ovarian cycle phase affects the timing of male sexual activity in free-ranging Barbary macaques (Macaca sylvanus) of Gibraltar. — Am. J. Primatol. 70: 44-53.

HenkelS.HeistermannM.FischerJ. (2010). Infants as costly social tools in male Barbary macaque networks. — Anim. Behav. 79: 1199-1204.

HenziS.P.ClarkeP.M.R.van SchaikC.P.PradhanG.R.BarrettL. (2010). Infanticide and reproductive restraint in a polygynous social mammal. — Proc. Natl. Acad. Sci. USA 107: 2130-2135.

HighamJ.P.MaestripieriD. (2010). Revolutionary coalitions in male rhesus macaques. — Behaviour 147: 1889-1908.

JansonC. (1984). Female choice and mating system of the brown capuchin monkey Cebus apella (primates: Cebidae). — Z. Tierpsychol. 65: 177-200.

JenningsD.J.CarlinC.M.GammellM.P. (2009). A winner effect supports third-party intervention behaviour during fallow deer, Dama dama, fights. — Anim. Behav. 77: 343-348.

JohnstoneR.A.DugatkinL.A. (2000). Coalition formation in animals and the nature of winner and loser effects. — Proc. Roy. Soc. Lond. B: Biol. Sci. 267: 17-21.

KoenigA.BorriesC.SuarezS.KreetiyutanontK.PrabnasukJ. (2004). Socio-ecology of Phayre’s leaf monkeys (Trachypithecus phayrei) at Phu Khieo Wildlife Sanctuary. — J. Wildl. Thailand 12: 150-163.

KuesterJ.PaulA. (1984). Female reproductive characteristics in semifree-ranging Barbary macaques (Macaca sylvanus L. 1758). — Folia Primatol. 43: 69-83.

KuesterJ.PaulA. (1992). Influence of male competition and female mate choice on male mating success in Barbary macaques (Macaca sylvanus). — Behaviour 120: 192-216.

KutsukakeN.NunnC. (2006). Comparative tests of reproductive skew in male primates: the roles of demographic factors and incomplete control. — Behav. Ecol. Sociobiol. 60: 695-706.

LangergraberK.MitaniJ.VigilantL. (2007). The limited impact of kinship on cooperation in wild chimpanzees. — Proc. Natl. Acad. Sci. USA 104: 7786-7790. VriesH. (2011). Testing steepness of dominance hierarchies. — In: R package version 0.2 available online at

LuA.BeehnerJ.C.CzekalaN.M.BorriesC. (2012). Juggling priorities: female mating tactics in Phayre’s leaf monkeys. — Am. J. Primatol. 74: 471-481.

MaestripieriD.RoneyJ. (2005). Primate copulation calls and postcopulatory female choice. — Behav. Ecol. 16: 106-113.

MitaniJ. (2009). Male chimpanzees form enduring and equtable social bonds. — Anim. Behav. 77: 633-640.

MitaniJ.C. (2006). Reciprocal exchange in chimpanzees and other primates. — In: Cooperation in primates and humans ( KappelerP.van SchaikC. eds). SpringerHeidelberg p.  107-120.

NishidaT. (1983). Alpha status and agonsitic alliance in wild chimpanzees. — Primates 24: 318-336.

NoëR. (1990). A veto game played by baboons: a challenge to the use of the Prisoner’s Dilemma as a paradigm for reciprocity and cooperation. — Anim. Behav. 39: 78-90.

NoëR. (1994). A model of coalition formation among male baboons with fighting ability as the crucial parameter. — Anim. Behav. 47: 211-213.

NoëR.SluijterA.A. (1990). Reproductive tactics of male savanna baboons. — Behaviour 113: 117-169.

NoëR.SluijterA.A. (1995). Which adult male savanna baboons form coalitions?Int. J. Primatol. 16: 77-105.

NunnC.L. (1999). The number of males in primate groups: a comparative test of the socioecological model. — Behav. Ecol. Sociobiol. 46: 1-13.

OstnerJ.SchülkeO. (2014). The evolution of social bonds in primate males. — Behaviour 151: 871-906.

OstnerJ.NunnC.L.SchülkeO. (2008). Female reproductive synchrony predicts skewed paternity across primates. — Behav. Ecol. 19: 1150-1158.

OstnerJ.HeistermannM.SchülkeO. (2011). Male competition and its hormonal correlates in Assamese macaques (Macaca assamensis). — Horm. Behav. 59: 105-113.

PackerC. (1979). Male dominance and reproductive activity in Papio anubis. — Anim. Behav. 27: 37-45.

PanditS.van SchaikC. (2003). A model for leveling coalitions among primate males: toward a theory of egalitarianism. — Behav. Ecol. Sociobiol. 55: 161-168.

PaulA.KuesterJ.ArnemannJ. (1996). The sociobiology of male–infant interactions in barbary macaques, Macaca sylvanus. — Anim. Behav. 51: 155-170.

R Development Core Team (2012). R: a language and environment for statistical computing. — R Foundation for Statistical ComputingVienna available online at

SchülkeO.BhagavatulaJ.VigilantL.OstnerJ. (2010). Social bonds enhance reproductive success in male macaques. — Curr. Biol. 220: 2207-2210.

SilkJ.B. (2002). Practice random acts of aggression and senseless acts of intimidation: the logic of status contests in social groups. — Evol. Anthropol. 11: 221-225.

SmallM. (1990). Promiscuity in Barbary Macaques (Macaca sylvanus). — Am. J. Primatol. 20: 267-282.

SmithJ.E.Van HornR.C.PowningK.S.ColeA.R.GrahamK.E.MemenisS.K.HolekampK.E. (2010). Evolutionary forces favoring intragroup coalitions among spotted hyenas and other animals. — Behav. Ecol. 21: 284-303.

StamatopoulosG.SenguptaA.VogelE.JansonC. (2009). A game-theoretic model of coalition formation among primates. — J. Bioecon. 11: 165-183.

ThierryB.SinghM.KaumannsW. (2004). Macaque societies — a model for the study of social organization. — Cambridge University PressCambridge.

TriversR.L. (1972). Parental investment and sexual selection. — In: Sexual selection and the descent of man 1871–1971 ( CampbellB. ed.). HeinemannLondon p.  136-179.

van HooffJ.A.R.A.M.van SchaikC.P. (1992). Cooperation in competition: the ecology of primate bonds. — In: Coalitions and alliances in humans and other animals ( WaalF.B.M. eds). Oxford University PressOxford p.  357-389.

van SchaikC.PanditS.VogelE. (2004). A model for within-group coalitionary aggression among males. — Behav. Ecol. Sociobiol. 57: 101-109.

van SchaikC.PanditS.VogelE. (2006). Toward a general model for male–male coalitions in primate groups. — In: Cooperation in primates and humans ( KappelerP.van SchaikC. eds). SpringerHeidelberg p.  151-172.

WhiteheadH.ConnorR. (2005). Alliances I. How large should alliances be?Anim. Behav. 69: 117-126.

WiddigA.StreichW.J.TembrockG. (2000). Coalition formation among male Barbary macaques (Macaca sylvanus). — Am. J. Primatol. 50: 37-51.

WroblewskiE.E.MurrayC.M.KeeleB.F.Schumacher-StankeyJ.C.HahnB.H.PuseyA.E. (2009). Male dominance rank and reproductive success in chimpanzees, Pan troglodytes schweinfurthii. — Anim. Behav. 77: 873-885.

YoungC.HähndelS.MajoloB.SchülkeO.OstnerJ. (2013a). Male coalitions and female behaviour affect male mating success independent of dominance rank and female receptive synchrony in wild Barbary macaques. — Behav. Ecol. Sociobiol. 67: 1665-1677.

YoungC.MajoloB.HeistermannM.SchülkeO.OstnerJ. (2013b). Male mating behaviour in relation to female sexual swellings, socio-sexual behaviour and hormonal changes in wild Barbary macaques. — Horm. Behav. 63: 32-39.

ZabelC.GlickmanS.FrankL.WoodmanseeK.KeppelG. (1992). Coalition formation in a colony of prepubertal spotted hyaenas. — In: Coalitions and alliances in humans and other animals ( WaalF.B.M. eds). Oxford University PressOxford p.  113-136.


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    Two males simultaneously aggressing a common target (on the right) in a coalitionary attack. The common target is another male who is carrying an infant (a common behaviour in male Barbary macaques). This figure is published in colour in the online edition of this journal, which can be accessed via

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    Percentage of all-up against all-down coalitions comparing all mating seasons, including the Sc08 (Berghänel et al., 2010) and Sc06 (Bissonnette et al., 2011) mating seasons. The percentage of each coalition type was calculated from the total number of coalitions occurring each mating season, including bridging coalitions.

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