American Journal of Primatology 56:215–230 (2002) © 2002 Wiley-Liss, Inc. Counter Aggression and Reconciliation in Assamese Macaques (Macaca assamensis) MATTHEW A. COOPER* AND IRWIN S. BERNSTEIN Department of Psychology, University of Georgia, Athens, Georgia Patterns of aggressive and affiliative behavior, such as counter aggres- sion and reconciliation, are said to covary in the genus Macaca; this is referred to as the systematic variation hypothesis. These behavior pat- terns constitute a species dominance style. Van Schaik’s [1989] socio- ecological model explains dominance style in macaques in terms of within- and between-group contest competition. Dominance style is also said to correlate with phylogeny in macaques. The present study was under- taken to examine phylogenetic and socioecological explanations of domi- nance style, as well as the systematic variation hypothesis. We collected data on counter aggression and reconciliation from a habituated group of Assamese macaques (Macaca assamensis) at the Tukeswari Temple in Assam, India. The proportion of agonistic episodes that involved counter aggression was relatively low. Counter aggression, however, occurred more often among males than among females, and it was most common when females initiated aggression against males. The conciliatory tendency for this group of Assamese macaques was 11.2%. The frequency of reconcili- ation was low for fights among males and for fights among females, but reconciliation was particularly rare for opposite-sexed opponents. Female social relationships were consistent with the systematic variation hypoth- esis, and suggest a despotic dominance style. A despotic dominance style in Assamese macaques weakens the correlation between dominance style and phylogeny in macaques, but it is not inconsistent with the socio- ecological model. Male–female relationships were not well explained by the despotic-egalitarian framework, and males may well have more tol- erant social relationships than do females. Sex differences need to be considered when categorizing species according to dominance style. Am. J. Primatol. 56:215–230, 2002. © 2002 Wiley-Liss, Inc. Key words: Macaca assamensis; reconciliation; counter aggression; dominance style; sex differences Contract grant sponsor: National Geographic Society; Contract grant number: 5862-97. *Correspondence to: Matthew Cooper, Center for Brain Science and Health, Georgia State Univer- sity, 24 Peachtree Center Ave. NE, Atlanta, GA 30303. E-mail: biomcc@langate.gsu.edu Received 28 February 2000; revision accepted 30 January 2002 DOI: 10.1002/ajp.1076 Published online in Wiley InterScience (www.interscience.wiley.com).