Skip navigation
Skip navigation

Investigating the 'dear enemy' phenomenon in the territory defence of the fiddler crab, Uca mjoebergi

Booksmythe, Isobel; Jennions, Michael; Backwell, Patricia

Description

Territory owners often respond with greater aggression to strangers than to neighbouring individuals, a phenomenon known as the 'dear enemy' effect. As strangers are usually 'floating' individuals seeking to acquire a territory they pose a relatively greater threat to a resident than do neighbours, who are already territory owners. This explains why residents are less aggressive towards neighbours but not how they distinguish neighbours from strangers: do residents recognize their neighbours or...[Show more]

dc.contributor.authorBooksmythe, Isobel
dc.contributor.authorJennions, Michael
dc.contributor.authorBackwell, Patricia
dc.date.accessioned2015-12-10T22:54:54Z
dc.identifier.issn0003-3472
dc.identifier.urihttp://hdl.handle.net/1885/59850
dc.description.abstractTerritory owners often respond with greater aggression to strangers than to neighbouring individuals, a phenomenon known as the 'dear enemy' effect. As strangers are usually 'floating' individuals seeking to acquire a territory they pose a relatively greater threat to a resident than do neighbours, who are already territory owners. This explains why residents are less aggressive towards neighbours but not how they distinguish neighbours from strangers: do residents recognize their neighbours or respond to differences in the behaviour of neighbours and strangers? Using measures of fighting intensity we investigated the dear enemy effect in a fiddler crab, Uca mjoebergi. We then experimentally manipulated the residency status of pairs of neighbours to distinguish between mechanisms enabling the dear enemy response. Fights between resident and nonterritory-owning individuals were longer and more escalated than fights between neighbouring residents, whether the nonterritory-owner was familiar (a former neighbour) or unfamiliar to the resident. Our results are consistent with the 'relative threat' hypothesis to explain the dear enemy effect, and support the suggestion that residents use cues in the behaviour of an intruder to determine the level of threat posed and distinguish between neighbours and strangers. However, we note that the observed patterns can occur even if residents do not differentiate between intruder types, and simply respond appropriately to the aggressiveness and persistence of an intruder.
dc.publisherAcademic Press
dc.sourceAnimal Behaviour
dc.subjectKeywords: aggression; behavioral response; crab; defense behavior; Decapoda (Crustacea); Ocypodidae; Uca dear enemy; fiddler crab; floater; neighbour; relative threat; stranger; territory; Uca mjoebergi
dc.titleInvestigating the 'dear enemy' phenomenon in the territory defence of the fiddler crab, Uca mjoebergi
dc.typeJournal article
local.description.notesImported from ARIES
local.identifier.citationvolume79
dc.date.issued2010
local.identifier.absfor060201 - Behavioural Ecology
local.identifier.ariespublicationu9511635xPUB510
local.type.statusPublished Version
local.contributor.affiliationBooksmythe, Isobel, College of Medicine, Biology and Environment, ANU
local.contributor.affiliationJennions, Michael, College of Medicine, Biology and Environment, ANU
local.contributor.affiliationBackwell, Patricia, College of Medicine, Biology and Environment, ANU
local.description.embargo2037-12-31
local.bibliographicCitation.startpage419
local.bibliographicCitation.lastpage423
local.identifier.doi10.1016/j.anbehav.2009.11.020
dc.date.updated2016-02-24T12:06:27Z
local.identifier.scopusID2-s2.0-74649085405
local.identifier.thomsonID000273986300022
CollectionsANU Research Publications

Download

File Description SizeFormat Image
01_Booksmythe_Investigating_the_'dear_enemy'_2010.pdf166.27 kBAdobe PDF    Request a copy


Items in Open Research are protected by copyright, with all rights reserved, unless otherwise indicated.

Updated:  19 May 2020/ Responsible Officer:  University Librarian/ Page Contact:  Library Systems & Web Coordinator