Editing Ethology (section)

== Mating and the fight for supremacy ==

[[File:Courtship of sarus cranes.jpg|thumb|[[Courtship display]] of a [[sarus crane]] ]]

Individual [[reproduction]] is the most important phase in the proliferation of individuals or genes within a species: for this reason, there exist complex [[mating]] [[ritual]]s, which can be very complex even if they are often regarded as fixed action patterns. The [[stickleback]]'s complex mating ritual, studied by Tinbergen, is regarded as a notable example.<ref>{{cite journal |last1=Tinbergen |first1=Niko |author1-link=Niko Tinbergen |last2=Van Iersel |first2=J. J. A. |title='Displacement Reactions' in the Three-Spined Stickleback |journal=Behaviour |date=1947 |volume=1 |issue=1 |pages=56–63 |jstor=4532675|doi=10.1163/156853948X00038 }}</ref>

Often in [[social relation|social life]], animals fight for the right to reproduce, as well as social supremacy. A common example of fighting for social and sexual supremacy is the so-called [[pecking order]] among [[poultry]]. Every time a group of poultry cohabitate for a certain time length, they establish a pecking order. In these groups, one chicken dominates the others and can peck without being pecked. A second chicken can peck all the others except the first, and so on. Chickens higher in the pecking order may at times be distinguished by their healthier appearance when compared to lower level chickens.{{Citation needed|date=June 2020}} While the pecking order is establishing, frequent and violent fights can happen, but once established, it is broken only when other individuals enter the group, in which case the pecking order re-establishes from scratch.<ref>{{cite journal |last=Rajecki |first=D. W. |date=1988 |title=Formation of leap orders in pairs of male domestic chickens |journal=Aggressive Behavior |volume=14 |issue=6 |pages=425–436|doi=10.1002/1098-2337(1988)14:6<425::AID-AB2480140604>3.0.CO;2-# |s2cid=141664966 }}</ref>