Dominance hierarchies emerge as a result of [[intersexual selection|intersexual]] and [[intrasexual selection|intrasexual]] selection within groups, where competition between individuals[[conspecifics]] results in differential access to resources and mating opportunities. This can be mapped across a spectrum of social organization ranging from egalitarian to despotic, varying across multiple dimensions of cooperation and competition in between.<ref name="Klass Cords pp. 1299–1315">{{cite journal |last1=Klass |first1=Keren |last2=Cords |first2=Marina |title=Agonism and dominance in female blue monkeys |journal=American Journal of Primatology |publisher=[[Wiley (publisher)|Wiley]] |volume=77 |issue=12 |date=17 September 2015 |doi=10.1002/ajp.22481 |pages=1299–1315 |pmid=26378396 |s2cid=8725428 }}</ref> Conflict can be resolved in multiple ways, including aggression, tolerance, and avoidance. These are produced by social decision-making, described in the "relational model" created by the zoologist [[Frans De Waal]].<ref>{{cite book |last1=de Waal |first1=Frans B. M. |author1-link=Frans de Waal |last2=Aureli |first2=Filippo |editor1-last=Carter |editor1-first=Carol Sue |editor2-last=Lederhendler |editor2-first=I. Izja |editor3-last=Kirkpatrick |editor3-first=Brian |title=The Integrative Neurobiology of Affiliation |date=1999 |publisher=[[MIT Press]] |isbn=978-0-26253-158-0 |pages=119–140 |chapter-url=https://books.google.com/books?id=Im8FJJzjJUsC&pg=PA119 |chapter=Conflict Resolution and Distress Alleviation in Monkeys and Apes }}</ref> In systems where competition between and within the sexes is low, social behaviour gravitates towards tolerance and egalitarianism, such as that found in [[Muriqui|woolley spider monkeys]].<ref name="Hooper Kaplan Jaeggi 2021">{{cite journal |last1=Hooper |first1=Paul L. |last2=Kaplan |first2=Hillard S. |last3=Jaeggi |first3=Adrian V. |title=Gains to cooperation drive the evolution of egalitarianism |journal=Nature Human Behaviour |volume=5 |issue=7 |date=1 March 2021 |doi=10.1038/s41562-021-01059-y |pages=847–856|pmid=33649461 |s2cid=232089497 }}</ref><ref>{{cite book |last=Strier |first=Karen |title=Primate Behavioural Ecology |publisher=Pearson Education |year=2006 |page=5}}</ref> In despotic systems where competition is high, one or two members are dominant while all other members of the living group are equally submissive, as seen in Japanese and rhesus macaques, [[leopard geckos]], [[Phodopus|dwarf hamsters]]<!--inc [[Campbell's dwarf hamster]]-->, [[gorilla]]s, the cichlid ''[[Neolamprologus pulcher]]'', and [[lycaon pictus|African wild dog]].<ref>{{cite book |last=Alcock |first=John |title=Animal Behavior: An Evolutionary Approach |publisher=Sinauer Associates |year=2018 |pages=476–511}}</ref><ref name="Matsumura1999">{{cite journal |last=Matsumura |first=Shuichi |title=The evolution of "egalitarian" and "despotic" social systems among macaques |journal=Primates |volume=40 |issue=1 |year=1999 |pages=23–31 |doi=10.1007/BF02557699 |pmid=23179529 |s2cid=23652944 }}</ref> Linear ranking systems, or "pecking orders", which tend to fall in between egalitarianism and despotism, follow a structure where every member of the group is recognized as either dominant or submissive relative to every other member. This results in a linear distribution of rank, as seen in [[spotted hyena]]s and brown hyenas.<ref>{{Cite journal |last1=Watts |first1=Heather E. |last2=Holekamp |first2=Kay E. |s2cid=7723322 |date=2007-08-21 |title=Hyena societies |journal=Current Biology |volume=17 |issue=16 |pages=R657–R660 |doi=10.1016/j.cub.2007.06.002 |pmid=17714659 |doi-access=free |bibcode=2007CBio...17.R657W }}</ref>
