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Jungwirth A, Zöttl M, Bonfils D, Josi D, Frommen JG, Taborsky M. Philopatry yields higher fitness than dispersal in a cooperative breeder with sex-specific life history trajectories. SCIENCE ADVANCES 2023; 9:eadd2146. [PMID: 36867697 PMCID: PMC9984175 DOI: 10.1126/sciadv.add2146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Social evolution is tightly linked to dispersal decisions, but the ecological and social factors selecting for philopatry or dispersal often remain obscure. Elucidating selection mechanisms underlying alternative life histories requires measurement of fitness effects in the wild. We report on a long-term field study of 496 individually marked cooperatively breeding fish, showing that philopatry is beneficial as it increases breeding tenure and lifetime reproductive success in both sexes. Dispersers predominantly join established groups and end up in smaller groups when they ascend to dominance. Life history trajectories are sex specific, with males growing faster, dying earlier, and dispersing more, whereas females more likely inherit a breeding position. Increased male dispersal does not seem to reflect an adaptive preference but rather sex-specific differences in intrasexual competition. Cooperative groups may thus be maintained because of inherent benefits of philopatry, of which females seem to get the greater share in social cichlids.
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Affiliation(s)
- Arne Jungwirth
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, Savoyenstraße 1a, A-1160 Vienna, Austria
| | - Markus Zöttl
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar, Sweden
| | - Danielle Bonfils
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
| | - Dario Josi
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Eawag Swiss Federal Institute of Aquatic Science and Technology, CH-6047 Kastanienbaum, Switzerland
| | - Joachim G. Frommen
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Ecology and Environment Research Centre, Department of Natural Sciences, Manchester Metropolitan University, Chester Street, M1 5GD Manchester, United Kingdom
| | - Michael Taborsky
- Division of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Max Planck Institute of Animal Behavior, D-78467 Konstanz, Germany
- Institute for Advanced Study (Wissenschaftskolleg) Berlin, D-14193 Berlin, Germany
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2
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Braga Goncalves I, Radford AN. Experimental evidence that intruder and group member attributes affect outgroup defence and associated within-group interactions in a social fish. Proc Biol Sci 2019; 286:20191261. [PMID: 31594516 PMCID: PMC6790772 DOI: 10.1098/rspb.2019.1261] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In many social species, individuals communally defend resources from conspecific outsiders. Participation in defence and in associated within-group interactions, both during and after contests with outgroup rivals, is expected to vary between group members because the threat presented by different outsiders is not the same to each individual. However, experimental tests examining both the contributions to, and the consequences of, outgroup conflict for all group members are lacking. Using groups of the cichlid Neolamprologus pulcher, we simulated territorial intrusions by different-sized female rivals and altered the potential contribution of subordinate females to defence. Dominant females and subordinate females defended significantly more against size- and rank-matched intruders, while males displayed lower and less variable levels of defence. Large and small, but not intermediate-sized, intruders induced increased levels of within-group aggression during intrusions, which was targeted at the subordinate females. Preventing subordinate females from helping in territorial defence led to significant decreases in post-contest within-group and female-specific submissive and affiliative displays. Together, these results show that the defensive contributions of group members vary greatly depending both on their own traits and on intruder identity, and this variation has significant consequences for within-group social dynamics both during and in the aftermath of outgroup contests.
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Affiliation(s)
- Ines Braga Goncalves
- School of Biological Sciences/Life Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Andrew N Radford
- School of Biological Sciences/Life Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
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3
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Teunissen N, Kingma SA, Hall ML, Hidalgo Aranzamendi N, Komdeur J, Peters A. More than kin: subordinates foster strong bonds with relatives and potential mates in a social bird. Behav Ecol 2018. [DOI: 10.1093/beheco/ary120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Niki Teunissen
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Sjouke A Kingma
- Behavioural and Physiological Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
- Max Planck Institute for Ornithology, Vogelwarte Radolfzell, Radolfzell, Germany
| | - Michelle L Hall
- School of BioSciences, University of Melbourne, Parkville, Victoria, Australia
- Max Planck Institute for Ornithology, Vogelwarte Radolfzell, Radolfzell, Germany
| | | | - Jan Komdeur
- Behavioural and Physiological Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands
| | - Anne Peters
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
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Bachmann JC, Cortesi F, Hall MD, Marshall NJ, Salzburger W, Gante HF. Real-time social selection maintains honesty of a dynamic visual signal in cooperative fish. Evol Lett 2017; 1:269-278. [PMID: 30283655 PMCID: PMC6121853 DOI: 10.1002/evl3.24] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 08/21/2017] [Accepted: 09/01/2017] [Indexed: 01/04/2023] Open
Abstract
Our understanding of animal communication has been largely driven by advances in theory since empirical evidence has been difficult to obtain. Costly signaling theory became the dominant paradigm explaining the evolution of honest signals, according to which communication reliability relies on differential costs imposed on signalers to distinguish animals of different quality. On the other hand, mathematical models disagree on the source of costs at the communication equilibrium. Here, we present an empirical framework to study the evolution of honest signals that generates predictions on the form, function, and sources of reliability of visual signals. We test these predictions on the facial color patterns of the cooperatively breeding Princess of Burundi cichlid, Neolamprologus brichardi. Using theoretical visual models and behavioral experiments we show that these patterns possess stable chromatic properties for efficient transmission in the aquatic environment, while dynamic changes in signal luminance are used by the fish to communicate switches in aggressive intent. By manipulating signal into out-of-equilibrium expression and simulating a cheater invasion, we demonstrate that social costs (receiver retaliation) promote the honesty of this dynamic conventional signal. By directly probing the sender of a signal in real time, social selection is likely to be the mechanism of choice shaping the evolution of inexpensive, yet reliable context-dependent social signals in general.
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Affiliation(s)
- Judith C Bachmann
- Zoological Institute, Vesalgasse 1 University of Basel 4051 Basel Switzerland.,Department of Evolutionary Biology and Environmental Studies University of Zurich 8057 Zurich Switzerland
| | - Fabio Cortesi
- Zoological Institute, Vesalgasse 1 University of Basel 4051 Basel Switzerland.,Queensland Brain Institute University of Queensland Brisbane Queensland 4072 Australia
| | - Matthew D Hall
- School of Biological Sciences Monash University Melbourne 3800 Australia
| | - N Justin Marshall
- Queensland Brain Institute University of Queensland Brisbane Queensland 4072 Australia
| | - Walter Salzburger
- Zoological Institute, Vesalgasse 1 University of Basel 4051 Basel Switzerland
| | - Hugo F Gante
- Zoological Institute, Vesalgasse 1 University of Basel 4051 Basel Switzerland
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Balzarini V, Taborsky M, Villa F, Frommen JG. Computer animations of color markings reveal the function of visual threat signals in Neolamprologus pulcher. Curr Zool 2017; 63:45-54. [PMID: 29491962 PMCID: PMC5804153 DOI: 10.1093/cz/zow086] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 07/19/2016] [Indexed: 11/24/2022] Open
Abstract
Visual signals, including changes in coloration and color patterns, are frequently used by animals to convey information. During contests, body coloration and its changes can be used to assess an opponent's state or motivation. Communication of aggressive propensity is particularly important in group-living animals with a stable dominance hierarchy, as the outcome of aggressive interactions determines the social rank of group members. Neolamprologus pulcher is a cooperatively breeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical black stripes on the operculum that vary naturally in shape and darkness. During frontal threat displays these patterns are actively exposed to the opponent, suggesting a signaling function. To investigate the role of operculum stripes during contests we manipulated their darkness in computer animated pictures of the fish. We recorded the responses in behavior and stripe darkness of test subjects to which these animated pictures were presented. Individuals with initially darker stripes were more aggressive against the animations and showed more operculum threat displays. Operculum stripes of test subjects became darker after exposure to an animation exhibiting a pale operculum than after exposure to a dark operculum animation, highlighting the role of the darkness of this color pattern in opponent assessment. We conclude that (i) the black stripes on the operculum of N. pulcher are a reliable signal of aggression and dominance, (ii) these markings play an important role in opponent assessment, and (iii) 2D computer animations are well suited to elicit biologically meaningful short-term aggressive responses in this widely used model system of social evolution.
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Affiliation(s)
- Valentina Balzarini
- Institute of Ecology and Evolution, Behavioral Ecology Division, University of Bern, Wohlenstrasse 50a, 3032 Hinterkappelen, Switzerland
| | - Michael Taborsky
- Institute of Ecology and Evolution, Behavioral Ecology Division, University of Bern, Wohlenstrasse 50a, 3032 Hinterkappelen, Switzerland
| | - Fabienne Villa
- Institute of Ecology and Evolution, Behavioral Ecology Division, University of Bern, Wohlenstrasse 50a, 3032 Hinterkappelen, Switzerland
| | - Joachim G. Frommen
- Institute of Ecology and Evolution, Behavioral Ecology Division, University of Bern, Wohlenstrasse 50a, 3032 Hinterkappelen, Switzerland
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6
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Quiñones AE, van Doorn GS, Pen I, Weissing FJ, Taborsky M. Negotiation and appeasement can be more effective drivers of sociality than kin selection. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150089. [PMID: 26729929 PMCID: PMC4760191 DOI: 10.1098/rstb.2015.0089] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/18/2015] [Indexed: 11/12/2022] Open
Abstract
Two alternative frameworks explain the evolution of cooperation in the face of conflicting interests. Conflicts can be alleviated by kinship, the alignment of interests by virtue of shared genes, or by negotiation strategies, allowing mutually beneficial trading of services or commodities. Although negotiation often occurs in kin-structured populations, the interplay of kin- and negotiation-based mechanisms in the evolution of cooperation remains an unresolved issue. Inspired by the biology of a cooperatively breeding fish, we developed an individual-based simulation model to study the evolution of negotiation-based cooperation in relation to different levels of genetic relatedness. We show that the evolution of negotiation strategies leads to an equilibrium where subordinates appease dominants by conditional cooperation, resulting in high levels of help and low levels of aggression. This negotiation-based equilibrium can be reached both in the absence of relatedness and in a kin-structured population. However, when relatedness is high, evolution often ends up in an alternative equilibrium where subordinates help their kin unconditionally. The level of help at this kin-selected equilibrium is considerably lower than at the negotiation-based equilibrium, and it corresponds to a level reached when responsiveness is prevented from evolving in the simulations. A mathematical invasion analysis reveals that, quite generally, the alignment of payoffs due to the relatedness of interaction partners tends to impede selection for harsh but effective punishment of defectors. Hence kin structure will often hamper rather than facilitate the evolution of productive cooperation.
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Affiliation(s)
- Andrés E Quiñones
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, 3032 Hinterkappelen, Switzerland
| | - G Sander van Doorn
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Ido Pen
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Franz J Weissing
- Theoretical Research in Evolutionary Life Sciences, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Michael Taborsky
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, 3032 Hinterkappelen, Switzerland
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7
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Mirror, mirror on the wall: the predictive value of mirror tests for measuring aggression in fish. Behav Ecol Sociobiol 2014. [DOI: 10.1007/s00265-014-1698-7] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Riebli T, Taborsky M, Chervet N, Apolloni N, Zürcher Y, Heg D. Behavioural type, status and social context affect behaviour and resource allocation in cooperatively breeding cichlids. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.07.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Reddon AR, O'Connor CM, Marsh-Rollo SE, Balshine S. Effects of isotocin on social responses in a cooperatively breeding fish. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.07.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Hamilton IM, Ligocki IY. The extended personality: indirect effects of behavioural syndromes on the behaviour of others in a group-living cichlid. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.06.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Bruintjes R, Bonfils D, Heg D, Taborsky M. Paternity of subordinates raises cooperative effort in cichlids. PLoS One 2011; 6:e25673. [PMID: 22022428 PMCID: PMC3192049 DOI: 10.1371/journal.pone.0025673] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 09/09/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship. METHODOLOGY/PRINCIPAL FINDINGS We show that: (i) male subordinates gained paternity in 27.8% of all clutches and (ii) if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male) were detected on parentage and on helping behaviour. CONCLUSIONS/SIGNIFICANCE This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.
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Affiliation(s)
- Rick Bruintjes
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Hinterkappelen, Switzerland.
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Sefc KM. Mating and Parental Care in Lake Tanganyika's Cichlids. INTERNATIONAL JOURNAL OF EVOLUTIONARY BIOLOGY 2011; 2011:470875. [PMID: 21822482 PMCID: PMC3142683 DOI: 10.4061/2011/470875] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 03/22/2011] [Accepted: 05/02/2011] [Indexed: 11/20/2022]
Abstract
Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay.
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Affiliation(s)
- Kristina M. Sefc
- Department of Zoology, Karl-Franzens University Graz, Universitätsplatz 2, 8010 Graz, Austria
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15
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Behavioural type affects dominance and growth in staged encounters of cooperatively breeding cichlids. Anim Behav 2011. [DOI: 10.1016/j.anbehav.2010.11.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Schürch R, Rothenberger S, Heg D. The building-up of social relationships: behavioural types, social networks and cooperative breeding in a cichlid. Philos Trans R Soc Lond B Biol Sci 2010; 365:4089-98. [PMID: 21078660 PMCID: PMC2992742 DOI: 10.1098/rstb.2010.0177] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Consistent individual differences in behavioural types may not only cause variation in life-history decisions, but may also affect the choice of social partners and sociality in general. Here, we tested whether and how behavioural type influences the establishment of social ties using the cooperatively breeding cichlid, Neolamprologus pulcher. In a habitat saturation experiment with individuals pre-tested for behavioural type, we first analysed whether behavioural type affected the likelihood of settlement (i.e. social status), group sizes, and the types of dominant and subordinate individuals accepted as group members. Corrected for effects of body size and sex, the behavioural type did not affect settlement. However, bold dominant males only accepted smaller females, and grouped with bold subordinates, while shy dominant males accepted larger females than themselves, and grouped with shy subordinates. Second, we analysed the relationships between behavioural type and the aggressiveness or affiliation social network. Behavioural type significantly affected the number and quality of connections within the two networks. We show that behavioural types affect group composition, social networks and status achieved, in interaction with body size. Thus, the interactions within groups may depend not only on age, size and sex, but also on the behavioural type of the individuals involved.
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Affiliation(s)
- Roger Schürch
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Susan Rothenberger
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
| | - Dik Heg
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen, Switzerland
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Witsenburg F, Schürch R, Otti O, Heg D. Behavioural types and ecological effects in a natural population of the cooperative cichlid Neolamprologus pulcher. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.07.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Heg D, Taborsky M. Helper response to experimentally manipulated predation risk in the cooperatively breeding cichlid Neolamprologus pulcher. PLoS One 2010; 5:e10784. [PMID: 20520816 PMCID: PMC2877084 DOI: 10.1371/journal.pone.0010784] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 03/09/2010] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND We manipulated predation risk in a field experiment with the cooperatively breeding cichlid Neolamprologus pulcher by releasing no predator, a medium- or a large-sized fish predator inside underwater cages enclosing two to three natural groups. We assessed whether helpers changed their helping behaviour, and whether within-group conflict changed, depending on these treatments, testing three hypotheses: 'pay-to-stay' PS, 'risk avoidance' RA, or (future) reproductive benefits RB. We also assessed whether helper food intake was reduced under risk, because this might reduce investments in other behaviours to save energy. METHODOLOGY/PRINCIPAL FINDINGS Medium and large helpers fed less under predation risk. Despite this effect helpers invested more in territory defence, but not territory maintenance, under the risk of predation (supporting PS). Experimentally covering only the breeding shelter with sand induced more helper digging under predation risk compared to the control treatment (supporting PS). Aggression towards the introduced predator did not differ between the two predator treatments and increased with group member size and group size (supporting PS and RA). Large helpers increased their help ratio (helping effort/breeder aggression received, 'punishment' by the dominant pair in the group) in the predation treatments compared to the control treatment, suggesting they were more willing to PS. Medium helpers did not show such effects. Large helpers also showed a higher submission ratio (submission/ breeder aggression received) in all treatments, compared to the medium helpers (supporting PS). CONCLUSIONS/SIGNIFICANCE We conclude that predation risk reduces helper food intake, but despite this effect, helpers were more willing to support the breeders, supporting PS. Effects of breeder punishment suggests that PS might be more important for large compared to the medium helpers. Evidence for RA was also detected. Finally, the results were inconsistent with RB.
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Affiliation(s)
- Dik Heg
- Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Hinterkappelen, Switzerland.
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Arnold C, Taborsky B. Social experience in early ontogeny has lasting effects on social skills in cooperatively breeding cichlids. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2009.12.008] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Schürch R, Heg D. Variation in Helper Type Affects Group Stability and Reproductive Decisions in a Cooperative Breeder. Ethology 2010. [DOI: 10.1111/j.1439-0310.2009.01738.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Mitchell JS, Jutzeler E, Heg D, Taborsky M. Gender Differences in the Costs that Subordinate Group Members Impose on Dominant Males in a Cooperative Breeder. Ethology 2009. [DOI: 10.1111/j.1439-0310.2009.01705.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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