title: Contest outcome in a territorial butterfly: the role of motivation.
abstract: In many butterfly species, males compete over areas advantageous for encountering females. Rules for contest settlement are, however, largely unknown and neither morphological nor physiological traits can reliably predict the contest outcome. Here, we test the hypothesis that contests are settled in accordance with a motivation asymmetry. We staged contests between males of Pararge aegeria and after removing the resident, the non-resident was allowed (i) either to interact with a non-receptive female for 30 min (n = 30) or (ii) to spend 30 min alone in the cage (n = 30), after which the initial resident was reintroduced. The results show that males that had interacted with a female had a higher probability of becoming dominant and reversing contest outcome. Moreover, males that were faster to take over a vacant territory when the resident was removed were more likely to become dominant. Here, we show for the first time, to our knowledge, that frequent encounters with a mated female can increase male motivation to persist in a territorial contest in a butterfly. Further, we suggest that variation in intrinsic motivation reflects male eagerness to take over vacant territory. This study indicates that variation in resource value and motivational asymmetries are important for settling contests in butterflies.
authors.affiliation: Department of Zoology, Stockholm University, SE-106 91 Stockholm, Sweden. martin.bergman@zoologi.su.se
authors.forename: Martin
authors.initials: M
authors.lastname: Bergman
authors.forename: Martin
authors.initials: M
authors.lastname: Olofsson
authors.forename: Christer
authors.initials: C
authors.lastname: Wiklund
mesh_terms: D000818:Animals; D002080:Butterflies / Q000502:physiology*; D003163:Competitive Behavior; D005260:Female; D008297:Male; D009042:Motivation; D012726:Sexual Behavior, Animal; D013731:Territoriality; D013997:Time Factors
references.citation: Trends Ecol Evol. 2006 Jan;21(1):16-21
references.pmid: 16701465
references.citation: Zoolog Sci. 2006 Oct;23(10):863-72
references.pmid: 17116989
references.citation: Anim Behav. 1998 Sep;56(3):533-540
references.pmid: 9784200
references.citation: Anim Behav. 1998 May;55(5):1341-7
references.pmid: 9632517
references.citation: J Theor Biol. 1974 Sep;47(1):223-43
references.pmid: 4477626
references.citation: Nature. 2000 Feb 10;403(6770):613
references.pmid: 10688185
references.citation: Proc Biol Sci. 2008 Jul 7;275(1642):1517-24
references.pmid: 18364315
references.citation: Proc Biol Sci. 2004 Aug 22;271(1549):1707-11
references.pmid: 15306291
references.citation: Proc Biol Sci. 2007 Jul 7;274(1618):1659-65
references.pmid: 17472909
references.citation: Proc Biol Sci. 2002 Jul 7;269(1498):1341-5
references.pmid: 12079656