scholarly journals The fitness consequences of kin-biased dispersal in a cooperatively breeding bird

2015 ◽  
Vol 11 (7) ◽  
pp. 20150336 ◽  
Author(s):  
Lea Pollack ◽  
Dustin R. Rubenstein
Keyword(s):  
Social Rank ◽  
Group Living ◽  
Breeding Bird ◽  
Direct Benefits ◽  
Fitness Consequences ◽  
Cooperatively Breeding ◽  
Potential Benefits ◽  
Indirect Fitness ◽  
Living Species

Cooperative alliances among kin may not only lead to indirect fitness benefits for group-living species, but can also provide direct benefits through access to mates or higher social rank. However, the immigrant sex in most species loses any potential benefits of living with kin unless immigrants disperse together or recruit relatives into the group in subsequent years. To look for evidence of small subgroups of related immigrants within social groups (kin substructure), we used microsatellites to assess relatedness between immigrant females of the cooperatively breeding superb starling, Lamprotornis superbus. We determined how timing of immigration led to kin subgroup formation and if being part of one influenced female fitness. Although mean relatedness in groups was higher for males than females, 26% of immigrant females were part of a kin subgroup with a sister. These immigrant sibships formed through kin recruitment across years more often than through coalitions immigrating together in the same year. Furthermore, females were more likely to breed when part of a kin subgroup than when alone, suggesting that female siblings form alliances that may positively influence their fitness. Ultimately, kin substructure should be considered when determining the role of relatedness in the evolution of animal societies.

scholarly journals Nest predation predicts infanticide in a cooperatively breeding bird

2019 ◽  
Vol 15 (8) ◽  
pp. 20190314
Author(s):  
Yi-Ru Cheng ◽  
Dustin R. Rubenstein ◽  
Sheng-Feng Shen
Keyword(s):  
Nest Predation ◽  
Social Conflict ◽  
Alternative Hypothesis ◽  
Group Living ◽  
Breeding Birds ◽  
Breeding Bird ◽  
Parental Response ◽  
Cooperatively Breeding ◽  
Alternative Hypotheses ◽  
Living Species

In cooperatively breeding species, social conflict is typically assumed to underlie destructive behaviours like infanticide. However, an untested alternative hypothesis in birds is that infanticide in the form of egg tossing may simply be a parental response to partial nest predation representing a life-history trade-off. We examined egg tossing behaviour in the colonial and cooperatively breeding grey-capped social weaver ( Pseudonigrita arnaudi ), a plural breeder in which pairs nest separately, often in the same tree. Using infrared nest cameras, we found that 78% of the tossing events from 2012 to 2017 were committed by parents, suggesting that social conflict is unlikely to be the main reason underlying egg tossing in this species. Instead, reductions in clutch size due to both natural and experimentally simulated predation induced parental egg tossing. Our study suggests that destructive behaviour in cooperatively breeding birds can be shaped by a variety of mechanisms beyond social conflict and that alternative hypotheses must be considered when studying the adaptive significance of infanticide in group-living species.

scholarly journals A test of male infanticide as a reproductive tactic in a cichlid fish

2017 ◽  
Vol 4 (3) ◽  
pp. 160891 ◽  
Author(s):  
Shagun Jindal ◽  
Aneesh P. H. Bose ◽  
Constance M. O'Connor ◽  
Sigal Balshine
Keyword(s):  
Cichlid Fish ◽  
Group Living ◽  
Laboratory Setting ◽  
Dominant Position ◽  
Egg Cannibalism ◽  
Cooperatively Breeding ◽  
Dominant Individual ◽  
Living Species ◽  
Reproductive Tactic ◽  
Relative Body Size

Infanticide and offspring cannibalism are taxonomically widespread phenomena. In some group-living species, a new dominant individual taking over a group can benefit from infanticide if doing so induces potential mates to become reproductively available sooner. Despite widespread observations of infanticide (i.e. egg cannibalism) among fishes, no study has investigated whether egg cannibalism occurs in fishes as a result of group takeovers, or how this type of cannibalism might be adaptive. Using the cooperatively breeding cichlid, Neolamprologus pulcher , we tested whether new unrelated males entering the dominant position in a social group were more likely to cannibalize eggs, and whether such cannibalism would shorten the interval until the female's next spawning. Females spawned again sooner if their broods were removed than if they were cared for. Egg cannibalism occurred frequently after a group takeover event, and was rarer if the original male remained with the group. While dominant breeder females were initially highly aggressive towards newcomer males that took over the group, the degree of resistance depended on relative body size differences between the new pair and, ultimately, female aggression did not prevent egg cannibalism. Egg cannibalism, however, did not shorten the duration until subsequent spawning, or increase fecundity during subsequent breeding in our laboratory setting. Our results show that infanticide as mediated through group takeovers is a taxonomically widespread behaviour.

scholarly journals Methylation patterns at fledging predict delayed dispersal in a cooperatively breeding bird

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252227
Author(s):  
Andrea L. Liebl ◽  
Jeff S. Wesner ◽  
Andrew F. Russell ◽  
Aaron W. Schrey
Keyword(s):  
First Year ◽  
Breeding Bird ◽  
Delayed Dispersal ◽  
Genome Wide ◽  
A Genome ◽  
Cooperatively Breeding ◽  
Dispersal Behavior ◽  
Natal Habitat ◽  
Indirect Fitness ◽  
Methylation Patterns

Individuals may delay dispersing from their natal habitat, even after maturation to adulthood. Such delays can have broad consequences from determining population structure to allowing an individual to gain indirect fitness by helping parents rear future offspring. Dispersal in species that use delayed dispersal is largely thought to be opportunistic; however, how individuals, particularly inexperienced juveniles, assess their environments to determine the appropriate time to disperse is unknown. One relatively unexplored possibility is that dispersal decisions are the result of epigenetic mechanisms interacting between a genome and environment during development to generate variable dispersive phenotypes. Here, we tested this using epiRADseq to compare genome-wide levels of DNA methylation of blood in cooperatively breeding chestnut-crowned babblers (Pomatostomus ruficeps). We measured dispersive and philopatric individuals at hatching, before fledging, and at 1 year (following when first year dispersal decisions would be made). We found that individuals that dispersed in their first year had a reduced proportion of methylated loci than philopatric individuals before fledging, but not at hatching or as adults. Further, individuals that dispersed in the first year had a greater number of loci change methylation state (i.e. gain or lose) between hatching and fledging. The existence and timing of these changes indicate some influence of development on epigenetic changes that may influence dispersal behavior. However, further work needs to be done to address exactly how developmental environments may be associated with dispersal decisions and which loci in particular are manipulated to generate such changes.

scholarly journals Intergroup aggression in meerkats

2019 ◽  
Vol 286 (1917) ◽  
pp. 20191993 ◽  
Author(s):  
Mark Dyble ◽  
Thomas M. Houslay ◽  
Marta B. Manser ◽  
Tim Clutton-Brock
Keyword(s):  
Genetic Relatedness ◽  
Group Living ◽  
Lethal Violence ◽  
Suricata Suricatta ◽  
Group Cooperation ◽  
Fitness Consequences ◽  
Cooperatively Breeding ◽  
Adult Sex Ratio ◽  
Violent Conflicts ◽  
Large Groups

Violent conflicts between groups have been observed among many species of group living mammals and can have important fitness consequences, with individuals being injured or killed and with losing groups surrendering territory. Here, we explore between-group conflict among meerkats ( Suricata suricatta ), a highly social and cooperatively breeding mongoose. We show that interactions between meerkat groups are frequently aggressive and sometimes escalate to fighting and lethal violence and that these interactions have consequences for group territories, with losing groups moving to sleeping burrows closer to the centre of their territories following an intergroup interaction and with winning groups moving further away. We find that larger groups and groups with pups are significantly more likely to win contests, but that the location of the contest, adult sex ratio, and mean within-group genetic relatedness do not predict contest outcome. Our results suggest that intergroup competition may be a major selective force among meerkats, reinforcing the success of large groups and increasing the vulnerability of small groups to extinction. The presence of both within-group cooperation and between-group hostility in meerkats make them a valuable point of comparison in attempts to understand the ecological and evolutionary roots of human warfare.

scholarly journals The effects of familiarity and social hierarchy on group membership decisions in a social fish

2009 ◽  
Vol 6 (3) ◽  
pp. 301-303 ◽  
Author(s):  
Lyndon A. Jordan ◽  
Marian Y. L. Wong ◽  
Sigal S. Balshine
Keyword(s):  
Life History ◽  
Decision Process ◽  
Group Membership ◽  
Social Rank ◽  
Group Living ◽  
Social Hierarchy ◽  
Trade Off ◽  
The Social ◽  
Potential Benefits ◽  
Complex Decision

Members of animal groups face a trade-off between the benefits of remaining with a familiar group and the potential benefits of dispersing into a new group. Here, we examined the group membership decisions of Neolamprologus pulcher , a group-living cichlid. We found that subordinate helpers showed a preference for joining familiar groups, but when choosing between two unfamiliar groups, helpers did not preferentially join groups that maximized their social rank. Rather, helpers preferred groups containing larger, more dominant individuals, despite receiving significantly more aggression within these groups, possibly owing to increased protection from predation in such groups. These results suggest a complex decision process in N. pulcher when choosing among groups, dependent not only on familiarity but also on the social and life-history consequences of joining new groups.

Chemical cues and group association preferences in a subsocial cockroach, Panesthia australis

2009 ◽  
Vol 57 (6) ◽  
pp. 385 ◽  
Author(s):  
Zacariah D. Billingham ◽  
David G. Chapple ◽  
Paul Sunnucks ◽  
Bob B. M. Wong
Keyword(s):  
Chemical Cues ◽  
Social Systems ◽  
Group Living ◽  
Social Recognition ◽  
Restricted Gene Flow ◽  
Diverse Range ◽  
Living Species ◽  
Group Members ◽  
Wood Boring

An ability to recognise and discriminate between group and non-group members is essential for most group-living species. Several different sensory modalities may be utilised for social recognition, the most notable of which is olfaction. Among insects, members of the order Blattodea (cockroaches, termites) exhibit a diverse range of social systems and provide an excellent model for examining the role of chemical communication in group discrimination. We experimentally tested the importance of chemical cues in the association preferences of the subsocial Australian wood-boring cockroach, Panesthia australis. Using a series of dichotomous choice trials, we found that individuals preferred conspecific odour cues over those of an unscented peatmoss control. We then gave cockroaches a choice between the odour cues of cockroaches from different logs, and found that they did not exhibit a preference for the cues of individuals from their own log versus those from different logs within the same locality. However, cockroaches exhibited a strong preference for cues taken from individuals from a geographically distant population. Our findings suggest that P. australis engages in group discrimination, and that patterns of association may reflect an underlying preference for unfamiliar and/or genetically dissimilar individuals in a species encumbered by restricted gene flow.

scholarly journals Kinship affects investment by helpers in a cooperatively breeding bird

2010 ◽  
Vol 277 (1698) ◽  
pp. 3299-3306 ◽  
Author(s):  
Ki-Baek Nam ◽  
Michelle Simeoni ◽  
Stuart P. Sharp ◽  
Ben J. Hatchwell
Keyword(s):  
Cooperative Breeding ◽  
Kin Selection ◽  
Genetic Relatedness ◽  
Critical Role ◽  
Breeding Systems ◽  
Pedigree Information ◽  
Breeding Bird ◽  
Cooperatively Breeding ◽  
Indirect Fitness ◽  
Fitness Benefits

Helping behaviour in cooperative breeding systems has been attributed to kin selection, but the relative roles of direct and indirect fitness benefits in the evolution of such systems remain a matter of debate. In theory, helpers could maximize the indirect fitness benefits of cooperation by investing more in broods with whom they are more closely related, but there is little evidence for such fine-scale adjustment in helper effort among cooperative vertebrates. In this study, we used the unusual cooperative breeding system of the long-tailed tit Aegithalos caudatus to test the hypothesis that the provisioning effort of helpers was positively correlated with their kinship to broods. We first use pedigrees and microsatellite genotypes to characterize the relatedness between helpers and breeders from a 14 year field study. We used both pedigree and genetic approaches because long-tailed tits have access to pedigree information acquired through social relationships, but any fitness consequences will be determined by genetic relatedness. We then show using both pedigrees and genetic relatedness estimates that alloparental investment by helpers increases as their relatedness to the recipients of their care increases. We conclude that kin selection has played a critical role in moulding the investment decisions of helpers in this cooperatively breeding species.

scholarly journals Consequences of ‘load-lightening’ for future indirect fitness gains by helpers in a cooperatively breeding bird

2010 ◽  
Vol 79 (3) ◽  
pp. 529-537 ◽  
Author(s):  
Jessica Meade ◽  
Ki-Baek Nam ◽  
Andrew P. Beckerman ◽  
Ben J. Hatchwell
Keyword(s):  
Breeding Bird ◽  
Cooperatively Breeding ◽  
Indirect Fitness

scholarly journals The effect of boldness on decision-making in barnacle geese is group-size-dependent

2010 ◽  
Vol 278 (1714) ◽  
pp. 2018-2024 ◽  
Author(s):  
Ralf H. J. M. Kurvers ◽  
Vena M. A. P. Adamczyk ◽  
Sipke E. van Wieren ◽  
Herbert H. T. Prins
Keyword(s):  
Decision Making ◽  
Group Size ◽  
Group Living ◽  
Decision Making Process ◽  
Central Question ◽  
Size Dependent ◽  
Collective Decisions ◽  
Living Species ◽  
Barnacle Geese

In group-living species, decisions made by individuals may result in collective behaviours. A central question in understanding collective behaviours is how individual variation in phenotype affects collective behaviours. However, how the personality of individuals affects collective decisions in groups remains poorly understood. Here, we investigated the role of boldness on the decision-making process in different-sized groups of barnacle geese. Naive barnacle geese, differing in boldness score, were introduced in a labyrinth in groups with either one or three informed demonstrators. The demonstrators possessed information about the route through the labyrinth. In pairs, the probability of choosing a route prior to the informed demonstrator increased with increasing boldness score: bolder individuals decided more often for themselves where to go compared with shyer individuals, whereas shyer individuals waited more often for the demonstrators to decide and followed this information. In groups of four individuals, however, there was no effect of boldness on decision-making, suggesting that individual differences were less important with increasing group size. Our experimental results show that personality is important in collective decisions in pairs of barnacle geese, and suggest that bolder individuals have a greater influence over the outcome of decisions in groups.

Sign in / Sign up

Export Citation Format

Share Document