48 results on '"Cant, A."'
Search Results
2. Network‐level consequences of outgroup threats in banded mongooses: Grooming and aggression between the sexes
- Author
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Darren P. Croft, Samuel Ellis, Solomon Kyambulima, Faye J. Thompson, Elizabeth F. R. Preston, and Michael A. Cant
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Male ,0106 biological sciences ,Herpestidae ,Affect (psychology) ,010603 evolutionary biology ,01 natural sciences ,medicine ,Animals ,Cooperative Behavior ,Social Behavior ,Social network analysis ,health care economics and organizations ,Ecology, Evolution, Behavior and Systematics ,Internal conflict ,Banded mongoose ,biology ,Aggression ,010604 marine biology & hydrobiology ,Group conflict ,biology.organism_classification ,Grooming ,humanities ,Outgroup ,Female ,Animal Science and Zoology ,Intragroup conflict ,medicine.symptom ,Territoriality ,Psychology ,Social psychology - Abstract
Animal groups are heterogeneous assemblages of individuals with differing fitness interests, which may lead to internal conflict over investment in group territorial defence. Differences between individuals may lead to different behavioural responses to intergroup conflict, particularly between the sexes. These potential impacts have been little studied. We used social network analysis to investigate the impact of simulated intergroup conflicts on social relationships in groups of wild banded mongooses Mungos mungo, in which intergroup fights are more costly for males than females. We predicted that social cohesion (specifically male-to-male and female-to-male grooming) would increase after conflict, and aggression would decrease, to minimize conflict between the sexes. Simulated intergroup conflicts were performed by exposing banded mongoose groups to scents, 'war cry' playbacks, and live intruders from a rival group. All grooming and aggression interactions between individuals were recorded, and grooming and aggression social networks were created for the 2 days preceding a simulated intergroup conflict (pre-conflict network) and the 2 days after (post-conflict network). We found no evidence of an increase in social cohesion after simulated conflicts, measured as grooming eigenvector centrality. Male-to-male, male-to-female and female-to-male grooming strength decreased after simulated intrusions compared to female-to-female grooming strength. However, male-female aggression decreased in intrusion trials compared to other interaction types, consistent with the hypothesis that intergroup encounters reduce the level of intragroup conflict between males and females. Males were more affected socially by intergroup encounters than females, which may be because they are investing in defence rather than internal relationships. Focusing on individual relationship changes, using social network analysis, can reveal changes in the directionality of behaviour in response to intergroup encounters, and highlight how individual responses to conflict may scale up to affect social networks and, potentially, group performance. This study highlights the importance of studying both group-level behaviours and individual relationships to more fully understand responses to intergroup encounters.
- Published
- 2020
3. Extra-group paternity varies with proxies of relatedness in a social mammal with high inbreeding risk
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Joseph I. Hoffman, Emma I. K. Vitikainen, David A. Wells, Hazel J. Nichols, Harry H. Marshall, Michael A. Cant, Faye J. Thompson, Faculty of Biological and Environmental Sciences, Biosciences, Helsinki One Health (HOH), Evolution, Sociality & Behaviour, and Organismal and Evolutionary Biology Research Programme
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0106 biological sciences ,0303 health sciences ,Group (mathematics) ,Zoology ,Biology ,010603 evolutionary biology ,01 natural sciences ,behavioral plasticity ,cooperative breeder ,03 medical and health sciences ,extra-group paternity ,personality ,extrapair paternity ,1181 Ecology, evolutionary biology ,Animal Science and Zoology ,Mammal ,banded mongoose ,repeatability ,Inbreeding ,inbreeding avoidance ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology - Abstract
Behavioral mechanisms for avoiding inbreeding are common in the natural world and are believed to have evolved as a response to the negative consequences of inbreeding. However, despite a fundamental role in fitness, we have a limited understanding of the cues that individuals use to assess inbreeding risk, as well as the extent to which individual inbreeding behavior is repeatable. We used piecewise structural equation modeling of 24 years of data to investigate the causes and consequences of within- versus extra-group paternity in banded mongooses. This cooperatively breeding mammal lives in tight-knit social groups that often contain closely related opposite-sex breeders, so inbreeding can be avoided through extra-group mating. We used molecular parentage assignments to show that, despite extra-group paternity resulting in outbred offspring, within-group inbreeding occurs frequently, with around 16% litters being moderately or highly inbred. Additionally, extra-group paternity appears to be plastic, with females mating outside of their social group according to individual proxies (age and immigration status) and societal proxies (group size and age) of within-group inbreeding risk but not in direct response to levels of within-group relatedness. While individual repeatability in extra-group paternity was relatively low, female cobreeders showed high repeatability, suggesting a strong constraint arising from the opportunities for extra-group mating. The use of extra-group paternity as an inbreeding avoidance strategy is, therefore, limited by high costs, opportunity constraints, and the limited reliability of proxies of inbreeding risk.
- Published
- 2021
4. Intragroup competition predicts individual foraging specialisation in a group‐living mammal
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Sheppard, Catherine E., Inger, Richard, McDonald, Robbie A., Barker, Sam, Jackson, Andrew L., Thompson, Faye J., Vitikainen, Emma I. K., Cant, Michael A., and Marshall, Harry H.
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Male ,Mammals ,Letter ,Mungos mungo ,Ecology ,social group ,specialisation ,Feeding Behavior ,Banded mongoose ,Diet ,stable isotope ,Animals ,Female ,Letters ,foraging behaviour ,competition ,foraging niche ,group‐living - Abstract
Individual foraging specialisation has important ecological implications, but its causes in group‐living species are unclear. One of the major consequences of group living is increased intragroup competition for resources. Foraging theory predicts that with increased competition, individuals should add new prey items to their diet, widening their foraging niche (‘optimal foraging hypothesis’). However, classic competition theory suggests the opposite: that increased competition leads to niche partitioning and greater individual foraging specialisation (‘niche partitioning hypothesis’). We tested these opposing predictions in wild, group‐living banded mongooses (Mungos mungo), using stable isotope analysis of banded mongoose whiskers to quantify individual and group foraging niche. Individual foraging niche size declined with increasing group size, despite all groups having a similar overall niche size. Our findings support the prediction that competition promotes niche partitioning within social groups and suggest that individual foraging specialisation may play an important role in the formation of stable social groupings.
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- 2018
5. Individual and demographic consequences of mass eviction in cooperative banded mongooses
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Faye J. Thompson, Emma I. K. Vitikainen, Andrew J. Young, Michael A. Cant, and Harry H. Marshall
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0106 biological sciences ,education.field_of_study ,Banded mongoose ,Eviction ,biology ,Reproductive success ,05 social sciences ,Population ,Group conflict ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Conflict resolution strategy ,Biological dispersal ,0501 psychology and cognitive sciences ,Animal Science and Zoology ,050102 behavioral science & comparative psychology ,Social evolution ,education ,Social psychology ,Ecology, Evolution, Behavior and Systematics ,Demography - Abstract
In animal societies, conflict within groups can result in eviction, where individuals are often permanently expelled from their group. To understand the evolution of eviction and its role in the resolution of within-group conflict requires information on the demographic consequences of eviction for individuals and groups. However, such information is usually difficult to obtain because of the difficulty in tracking and monitoring individuals after they are evicted from their natal groups. Here we used a 15-year data set on life history and demography to investigate the consequences of eviction in a tractable cooperatively breeding mammal, the banded mongoose, Mungos mungo . In this species, groups of individuals are periodically evicted en masse and eviction is a primary mechanism by which new groups form in the study population. Following eviction, we found sex differences in dispersal distance: some females established new groups on the study peninsula but males always dispersed away from the study peninsula. Evicted females suffered reduced reproductive success in the year after eviction. For the evicting group, eviction was associated with increased per capita reproductive success for females, suggesting that eviction is successful in reducing reproductive competition. However, eviction was also associated with increased intergroup conflict for the evicting group. Our results suggest that within-group conflict resolution strategies affect group productivity, group interactions and the structure of the population, and hence have fitness impacts that reach beyond the individual evictors and evictees involved in eviction.
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- 2017
6. Stable isotopes are quantitative indicators of trophic niche
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Robbie A. McDonald, Richard Inger, Michael A. Cant, Faye J. Thompson, Harry H. Marshall, and Andrew L. Jackson
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0106 biological sciences ,Carbon Isotopes ,Ecology ,Nitrogen Isotopes ,Stable isotope ratio ,010604 marine biology & hydrobiology ,Nutritional Status ,stable isotopes ,Context (language use) ,Technical Comments ,niche overlap ,isotopic niche ,010603 evolutionary biology ,01 natural sciences ,Technical Comment ,Banded mongoose ,tissue integration time ,trophic niche ,Geography ,Isotopes ,Trophic niche ,diet ,Ecology, Evolution, Behavior and Systematics ,Ecosystem - Abstract
Hette‐Tronquart (2019, Ecol. Lett.) raises three concerns about our interpretation of stable isotope data in Sheppard et al. (2018, Ecol. Lett., 21, 665). We feel that these concerns are based on comparisons that are unreasonable or ignore the ecological context from which the data were collected. Stable isotope ratios provide a quantitative indication of, rather than being exactly equivalent to, trophic niche.
- Published
- 2019
7. Collective defence and behavioural homogeneity during simulated territorial intrusions in banded mongooses (Mungos mungo).
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Green, P.A., Preston, E.F.R., Nicholl, M.H., Croft, D.P., Thompson, F.J., Cant, M.A., and Taborsky, Barbara
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INTERGROUP relations ,MONGOOSES ,HOMOGENEITY ,SOCIAL influence ,ODORS ,TERRITORIAL marking (Animals) ,BLACK gram - Abstract
Conflicts between stable social groups ("intergroup conflicts") can be damaging and exert a strong influence on within‐group social behaviour. The success of groups during intergroup conflict may depend on the ability of individual group members to converge upon collective defence behaviour, such as approaching or attacking. In principle, collective defence can be achieved via a united front, in which each individual responds in the same way to an intergroup threat. We tested the impact of simulated intergroup conflicts on collective defence and individual behaviour in banded mongooses (Mungos mungo), a cooperatively breeding mammal in which intergroup conflict is particularly common and costly. We presented focal groups with scent markings, call playbacks and caged live animals from rival groups and compared their responses to these stimuli with their responses to own‐group control stimuli. A greater proportion of group members approached the stimulus and acted defensively in response to rival stimuli as compared to controls, consistent with a unified collective defence response. However, counter to our expectation, groups exhibited lower behavioural homogeneity when presented with rival stimuli as compared to controls. A closer examination of the behaviours competitors used revealed that lower homogeneity was driven by a greater use, and diversity, of defensive behaviours relevant to repelling simulated rivals. Finally, group size affected responses: as group size increased, the proportion of members approaching the stimulus and behavioural homogeneity decreased. Our results lend support to the hypothesis that intergroup conflict leads to coordinated collective defence behaviour during the immediate threat of an intergroup conflict. However, collective defence need not mean that all group members execute the same behaviours. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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8. Segmental concatenation of individual signatures and context cues in banded mongoose (Mungos mungo) close calls
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Jansen David AWAM, Cant Michael A, and Manser Marta B
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vocal signature ,vocal cue ,syllable ,close call ,segregation of information ,graded calls ,banded mongoose ,segmental concatenation ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background All animals are anatomically constrained in the number of discrete call types they can produce. Recent studies suggest that by combining existing calls into meaningful sequences, animals can increase the information content of their vocal repertoire despite these constraints. Additionally, signalers can use vocal signatures or cues correlated to other individual traits or contexts to increase the information encoded in their vocalizations. However, encoding multiple vocal signatures or cues using the same components of vocalizations usually reduces the signals' reliability. Segregation of information could effectively circumvent this trade-off. In this study we investigate how banded mongooses (Mungos mungo) encode multiple vocal signatures or cues in their frequently emitted graded single syllable close calls. Results The data for this study were collected on a wild, but habituated, population of banded mongooses. Using behavioral observations and acoustical analysis we found that close calls contain two acoustically different segments. The first being stable and individually distinct, and the second being graded and correlating with the current behavior of the individual, whether it is digging, searching or moving. This provides evidence of Marler's hypothesis on temporal segregation of information within a single syllable call type. Additionally, our work represents an example of an identity cue integrated as a discrete segment within a single call that is independent from context. This likely functions to avoid ambiguity between individuals or receivers having to keep track of several context-specific identity cues. Conclusions Our study provides the first evidence of segmental concatenation of information within a single syllable in non-human vocalizations. By reviewing descriptions of call structures in the literature, we suggest a general application of this mechanism. Our study indicates that temporal segregation and segmental concatenation of vocal signatures or cues is likely a common, but so far neglected, dimension of information coding in animal vocal communication. We argue that temporal segregation of vocal signatures and cues evolves in species where communication of multiple unambiguous signals is crucial, but is limited by the number of call types produced.
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- 2012
- Full Text
- View/download PDF
9. Spontaneous abortion as a response to reproductive conflict in the banded mongoose
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Gladys Kalema-Zikusoka, Harry H. Marshall, Emma I. K. Vitikainen, Emma Inzani, Michael A. Cant, Faye J. Thompson, Helsinki One Health (HOH), Evolution, Sociality & Behaviour, Ecology and Evolutionary Biology, Organismal and Evolutionary Biology Research Programme, and Faculty of Biological and Environmental Sciences
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0106 biological sciences ,Reproductive suppression ,Herpestidae ,Breeding ,SOCIAL-CONTROL ,EVICTION ,Biology ,Abortion ,010603 evolutionary biology ,01 natural sciences ,Pregnancy ,Animals ,Humans ,0501 psychology and cognitive sciences ,banded mongoose ,050102 behavioral science & comparative psychology ,reproductive and urinary physiology ,SUPPRESSION ,Evolutionary Biology ,CONSEQUENCES ,Banded mongoose ,Reproduction ,05 social sciences ,female reproductive competition ,biology.organism_classification ,abortion ,Agricultural and Biological Sciences (miscellaneous) ,EVOLUTION ,Abortion, Spontaneous ,Fertility ,cooperative species ,1181 Ecology, evolutionary biology ,Female ,reproductive suppression ,WEIGHT ,General Agricultural and Biological Sciences ,Limited resources ,Demography - Abstract
When breeding females compete for limited resources, the intensity of this reproductive conflict can determine whether the fitness benefits of current reproductive effort exceed the potential costs to survival and future fertility. In group-living species, reproductive competition can occur through post-natal competition among the offspring of co-breeding females. Spontaneous abortion could be a response to such competition, allowing females to curtail reproductive expenditure on offspring that are unlikely to survive and to conserve resources for future breeding opportunities. We tested this hypothesis using long-term data on banded mongooses, Mungos mungo , in which multiple females within a group give birth synchronously to a communal litter that is cared for by other group members. As predicted, abortions were more likely during dry periods when food is scarce, and in breeding attempts with more intense reproductive competition. Within breeding events, younger, lighter females carrying smaller fetuses were more likely to abort, particularly those that were also of lower rank. Our results suggest that abortion may be a means by which disadvantaged females conserve resources for future breeding attempts in more benign conditions, and highlight that female reproductive competition may be resolved long before the production of offspring.
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- 2019
10. Pregnancy is detected via odour in a wild cooperative breeder
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Hazel J. Nichols, Michael A. Cant, and Jessica J. Mitchell
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0106 biological sciences ,Dominance-Subordination ,Male ,Reproductive suppression ,Herpestidae ,media_common.quotation_subject ,Zoology ,Breeding ,010603 evolutionary biology ,01 natural sciences ,Competition (biology) ,Peer Group ,Sexual Behavior, Animal ,Pregnancy ,Cooperative breeding ,medicine ,Animals ,0501 psychology and cognitive sciences ,Uganda ,050102 behavioral science & comparative psychology ,reproductive and urinary physiology ,media_common ,Estrous cycle ,QL ,Banded mongoose ,biology ,Ecology ,Reproduction ,05 social sciences ,biology.organism_classification ,medicine.disease ,Olfactory Perception ,Agricultural and Biological Sciences (miscellaneous) ,Odorants ,Animal Behaviour ,Female ,General Agricultural and Biological Sciences ,Mungos - Abstract
Among mammals, scent has long been known to encode oestrus; however, in many species, detecting pregnancy may also be important in terms of both competition and mate-choice. Here, we show, through odour presentation experiments, that pregnancy is discernible via scent by both sexes in the cooperatively breeding banded mongoose, Mungos mungo . Males spent more time investigating and were more likely to scent mark the odours of non-pregnant females, compared to pregnant females. Females showed increased levels of scent marking when odours were of the same reproductive state as themselves. These results present the first direct demonstration that pregnancy is detectable via scent in wild cooperative breeders. Detecting pregnancy may be particularly important in cooperative breeders as, in addition to the competition between males for receptive mates, there is also intense competition between females for access to alloparental care. Consequently, dominant females benefit from targeting reproductive suppression towards subordinates that represent direct threats, such as pregnant females.
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- 2017
11. The origins of consistent individual differences in cooperation in wild banded mongooses, Mungos mungo
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Andrew J. Young, Iain Stott, Emma I. K. Vitikainen, Sarah J. Hodge, Michael A. Cant, and Jennifer L. Sanderson
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education.field_of_study ,Banded mongoose ,genetic structures ,Reproduction (economics) ,Niche ,Population ,Biology ,biology.organism_classification ,Specialization (functional) ,Animal Science and Zoology ,Social conflict ,Evolutionary ecology ,education ,Social psychology ,Mungos ,Ecology, Evolution, Behavior and Systematics ,Demography - Abstract
Individual differences in contributions to cooperation can be strikingly consistent over time giving rise to alternative cooperative phenotypes within animal societies. Following the social niche specialization hypothesis, these consistent differences may be driven by social conflict over reproductive opportunities if individuals specializing as ‘breeders’ and ‘nonbreeders’ experience a beneficial reduction in social conflict and differential costs associated with cooperating. This hypothesis gives three testable predictions: (1) consistent individual differences in cooperative behaviour will be accompanied by consistent individual differences in reproductive behaviour, (2) individuals contributing heavily to reproduction will contribute relatively little to cooperative behaviours within the same breeding attempt and vice versa, and (3) individuals that consistently contribute heavily to reproduction over their lifetime will also consistently contribute less to cooperative behaviours and vice versa. We tested these predictions with a 15-year investigation into the lifetime patterns of mate guarding and two forms of cooperative offspring care (‘babysitting’ and ‘escorting’) in a wild population of banded mongooses. We found significant repeatability of individual contributions to both cooperative behaviours, as well as significant repeatability of individual levels of mate guarding. However, we found no evidence of negative covariance between contributions to cooperative and reproductive behaviours either within breeding attempts or across lifetimes. This suggests that the observed consistent individual differences in both cooperative behaviour and reproduction are not associated; there is no evidence of a trade-off between reproduction and cooperation. However, we found a significant positive covariance between babysitting and escorting when estimated both within breeding attempts and across lifetimes, which suggests that some group members are generally more cooperative than others, contributing more to both behaviours over their lifetimes. The drivers of this consistent individual variation in contributions to cooperation remain unknown.
- Published
- 2015
12. Smelling fit: scent marking exposes parasitic infection status in the banded mongoose
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Hazel J. Nichols, Jessica J. Mitchell, Emma I. K. Vitikainen, and Michael A. Cant
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0106 biological sciences ,scent ,Toxocara ,Population ,Zoology ,Olfaction ,010603 evolutionary biology ,01 natural sciences ,Parasite load ,parasitic diseases ,0501 psychology and cognitive sciences ,050102 behavioral science & comparative psychology ,education ,education.field_of_study ,QL ,Banded mongoose ,Isospora ,biology ,Ecology ,QH ,05 social sciences ,Articles ,biology.organism_classification ,Mate choice ,Odor ,parasite ,scent preferences ,Animal Science and Zoology ,Mungos ,olfaction - Abstract
Preference for uninfected mates is presumed beneficial as it minimizes one’s risk of contracting an infection and infecting one’s offspring. In avian systems, visual ornaments are often used to indicate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where experimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load (estimated using fecal egg counts) and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.
- Published
- 2017
13. Heterozygosity but not inbreeding coefficient predicts parasite burdens in the banded mongoose
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Michael A. Cant, Emma I. K. Vitikainen, Hazel J. Nichols, Jessica J. Mitchell, and David A. Wells
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0106 biological sciences ,0301 basic medicine ,Genetics ,Linkage disequilibrium ,Genetic diversity ,QL ,Banded mongoose ,biology ,QH ,Zoology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Parasite load ,Loss of heterozygosity ,03 medical and health sciences ,QH301 ,030104 developmental biology ,Inbred strain ,Inbreeding depression ,Animal Science and Zoology ,Inbreeding ,Ecology, Evolution, Behavior and Systematics - Abstract
Inbreeding, reproduction between relatives, often impinges on the health and survival of resulting offspring. Such inbreeding depression may manifest itself through immunological costs as inbred individuals suffer increased propensity to disease, infection and parasites compared to outbred conspecifics. Here, we assess how the intestinal parasite loads of wild banded mongooses (Mungos mungo) vary with pedigree inbreeding coefficient (f) and standardized multi-locus heterozygosity. We find a significant association between increased heterozygosity and lower parasite loads; however, this correlation does not stand when considering f. Such findings may be explained by local genetic effects, linkage between genetic markers and genes influencing parasite burdens. Indeed, we find heterozygosity at certain loci to correlate with parasite load. Although these tentative local effects are lost following multiple test correction, they warrant future investigation to determine their strength and impact. We also suggest frequent inbreeding within banded mongooses may mean heterozygosity is a better predictor of inbreeding than pedigree f. This is because inbreeding facilitates linkage disequilibrium, increasing the chances of neutral markers representing genome-wide heterozygosity. Finally, neither f nor heterozygosity had a significant influence on the loads of two specific gastrointestinal parasites. Nevertheless, more heterozygous individuals benefited from reduced overall parasitic infection and genetic diversity appears to explain some variation in parasite burdens in the banded mongoose. © 2016 The Zoological Society of London.
- Published
- 2017
14. Testing for vocal individual discrimination in adult banded mongooses
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Marta B. Manser, Michael A. Cant, and David A. W. A. M. Jansen
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Banded mongoose ,biology ,Ecology ,Evolutionary biology ,Social relationship ,Animal Science and Zoology ,biology.organism_classification ,Mungos ,Ecology, Evolution, Behavior and Systematics - Abstract
The ability to individually recognize conspecifics is acknowledged as one of the prerequisites for the development of sophisticated social relationships in group-living species. It has been hypothesized that the discrimination of individual identities is crucial for the maintenance of social relationships and cooperation based on repeated interactions, and for the evolution of many social behaviours. Previous studies have shown that the close calls of the cooperatively breeding banded mongoose Mungos mungo are individually distinct. For instance, banded mongoose pups are able to distinguish between close calls of their escort and of a non-escort. In this study, we used playbacks based on the recently proposed violation-of-expectation paradigm and a dominance/age class recognition setup to investigate whether adult banded mongooses use the individual signature of close calls to distinguish among adult group members. We found no evidence that the individual signature in close calls is used to discriminate identity in banded mongooses. Based on the previous work, we suggest that this is not because banded mongooses are incapable of using signatures as a means of individual discrimination, but because the benefits of such discrimination are low. The study highlights the importance of understanding the function of a signal (e.g. the expected response), timing and the biology of the species when designing and performing playback experiments.
- Published
- 2013
15. Food availability shapes patterns of helping effort in a cooperative mongoose
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William Amos, Francis Mwanguhya, Matthew B.V. Bell, Michael A. Cant, Solomon Kyabulima, and Hazel J. Nichols
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Litter (animal) ,Banded mongoose ,biology ,Reproductive success ,Ecology ,Kin selection ,biology.organism_classification ,Mongoose ,biology.animal ,Animal Science and Zoology ,Carnivore ,Parental investment ,Mungos ,Ecology, Evolution, Behavior and Systematics ,Demography - Abstract
In cooperatively breeding vertebrate societies, contributions to offspring care can vary greatly between group members. Kin selection theory predicts that cooperation will be favoured when directed towards relatives and when the cost to benefit ratio is low. The fitness costs of helping in turn depend on the impact of energetic investments in care on future reproductive success, which is likely to vary between helpers. For example, investments may impact more on a young helper, which needs to invest energy in growth and is an inexperienced forager. We investigated how a key predictor of cost, food availability (estimated using rainfall), influences helping behaviour in the banded mongoose, Mungos mungo. In this cooperative carnivore, a variable number of group members breed while almost all help to rear the communal litter. Nonbreeding females and juvenile males helped less when food was scarce, reflecting the potentially high costs of weight loss and reduced growth on survival and future reproductive success. In contrast, adult males maintained their investment in care as food supply decreased, probably because body condition has relatively little impact on male reproductive success in this species. Breeding females (with pups in the communal litter) also maintained their helping effort as food supply decreased. Although mothers invested highly in care, there was no evidence that they preferentially cared for their own pups, probably because synchronized birthing scrambles maternity cues. Patterns of care in the banded mongoose thus seem to reflect the benefits gained from helping and the long-term fitness costs to the helper.
- Published
- 2012
16. Scent marking in wild banded mongooses: 1. Sex-specific scents and overmarking
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Peter Rüedi, Francis Mwanguhya, Solomon Kyabulima, Marta B. Manser, Neil R. Jordan, Michael A. Cant, University of Zurich, and Jordan, Neil R
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Banded mongoose ,Ecology ,Zoology ,Context (language use) ,Biology ,biology.organism_classification ,Sexual dimorphism ,10127 Institute of Evolutionary Biology and Environmental Studies ,1105 Ecology, Evolution, Behavior and Systematics ,Sexual selection ,Anal gland ,570 Life sciences ,biology ,590 Animals (Zoology) ,Animal Science and Zoology ,Animal communication ,1103 Animal Science and Zoology ,Paternal care ,Ecology, Evolution, Behavior and Systematics ,Sex ratio - Abstract
Overmarking occurs when one individual places its scent mark directly on top of the scent mark of another individual. Although it is almost ubiquitous among terrestrial mammals, we know little about the function of overmarking and detailed field observations are rare. We investigated the chemical composition of scents and patterns of overmarking by wild banded mongooses, Mungos mungo. Chemical analyses of anal gland secretions showed that scents were sexually dimorphic. Both male and female adults were more likely to overmark the scents of same-sex individuals. An analysis of responses to two scents on the same site suggested that the sex of the top or most recent scent was more important than that of the bottom or original scent in determining overmarking response. Juveniles also overmarked scents at high rates, but did not respond to scents in a sex-specific way. Same-sex-specific patterns within groups have not been described in any other species, and may reflect a social system with intense intrasexual competition for reproduction within both sexes. Banded mongooses live in large mixed-sex groups, with intense competition between males for females, owing to the heavily male-biased adult sex ratio and highly synchronized oestrous cycles. Oestrous synchronization may also promote intrasexual competition for males within females, as females compete simultaneously for high-quality males. Female competition for males may also be enhanced by the rewards of male-biased parental care. This investigation highlights the need for detailed studies of overmarking in the natural context, to confirm and expand upon laboratory findings.
- Published
- 2011
17. Scent marking in wild banded mongooses: 3. Intrasexual overmarking in females
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Francis Mwanguhya, Solomon Kyabulima, Michael A. Cant, Peter Rüedi, Neil R. Jordan, and Sarah J. Hodge
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Reproductive suppression ,Banded mongoose ,Ecology ,media_common.quotation_subject ,Zoology ,Olfaction ,Biology ,biology.organism_classification ,Animal Science and Zoology ,Mammal ,Animal communication ,Reproduction ,Mating ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
In contrast to numerous studies of scent marking in male mammals, studies of female scent marking are relatively rare. We have previously shown that communally breeding female banded mongooses, Mungos mungo, are more likely to overmark the scent of other females. Here we describe female overmarking patterns in more detail, and discuss these results in relation to hypotheses potentially explaining such ‘female intrasexual overmarking’. To our knowledge, this is the first study to investigate female overmarking in any wild mammal. First, although we found some evidence of individually distinctive scent marks in females, we found no evidence to suggest that female intrasexual overmarking was related to competition for food, as feeding competition was infrequent, and unrelated to overmarking scores. We also found no evidence to suggest that intrasexual overmarking in females was involved in reproductive suppression. Females with the highest and lowest overmarking scores in each group were mate-guarded by males for similar durations. Finally, we found little evidence to suggest that female intrasexual overmarking was involved in competition for males. Although the female with the highest overmarking score in each group tended to be mate-guarded by males in better condition than the female with the lowest overmarking score, a female’s overmarking score affected neither the amount of harassment she received from males nor the frequency of mating attempts received. These results are discussed in light of these and other untested hypotheses for female overmarking.
- Published
- 2011
18. Top males gain high reproductive success by guarding more successful females in a cooperatively breeding mongoose
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William Amos, Matthew B.V. Bell, Michael A. Cant, Hazel J. Nichols, and Sarah J. Hodge
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Banded mongoose ,Reproductive success ,biology ,Ecology ,media_common.quotation_subject ,Skew ,biology.organism_classification ,Mongoose ,Cooperative societies ,Mate choice ,Sexual selection ,biology.animal ,Animal Science and Zoology ,Reproduction ,Ecology, Evolution, Behavior and Systematics ,Demography ,media_common - Abstract
Of key importance for understanding cooperative societies is the way in which reproductive opportunities are distributed among group members. Traditionally, skew has been thought of as a product of intrasexual competition. However, cooperatively breeding species often live in mixed-sex groups, so the behaviour of one sex has the potential to influence skew in the other. We addressed the importance of inter- and intrasexual conflict in determining reproductive skew through a study of paternity sharing in the cooperatively breeding banded mongoose, Mungus mungo. Unlike banded mongoose females, where reproductive skew is low, males exhibited high skew, with 85% of paternities being assigned to the three oldest males in each group. Individual males appeared unable to monopolize reproduction because females come into oestrus in synchrony and mate multiply. Instead, older males increased their success by mate guarding the oldest, most fecund females. Our findings therefore highlight the importance of mate choice in males and reveal the behavioural differences between the sexes that generate reproductive skew. They also emphasize the considerable influence that female behaviour can have on male reproductive skew.
- Published
- 2010
19. Scent marking within and between groups of wild banded mongooses
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Michael A. Cant, Neil R. Jordan, Solomon Kyabulima, Francis Mwanguhya, and Peter Rüedi
- Subjects
Banded mongoose ,biology ,Ecology ,media_common.quotation_subject ,Territoriality ,biology.organism_classification ,Competition (biology) ,Social group ,Territorial defence ,Sexual selection ,Animal Science and Zoology ,Mating ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
Scent marking is commonly described as a territorial behaviour, and scent marks might deter potential intruders from entering occupied areas. Conspecific neighbours present both a reproductive and a territorial threat, thus, determining which, if any, of these threats shapes scent-marking behaviour is difficult. Banded mongooses Mungos mungo provide a rare clear separation between reproductive rivals (found within groups) and territorial rivals (neighbouring groups), because immigration into social groups is extremely rare, and mating occurs almost exclusively within groups. This situation offers an opportunity to assess the relative importance of territorial defence and intra-group competition for mates in shaping scent-marking behaviour. We combined detailed behavioural observations of scent marking, chemical analyses of scent composition and discrimination experiments in the field, and found little evidence for higher rates of scent marking in overlapping areas, a lack of group specificity of scents and a failure of individuals to discriminate between the scents of different groups. Although scent may fulfill some role in territorial demarcation and defence, these results suggest that scent marks and scent-marking patterns are also involved in communicating within social groups.
- Published
- 2009
20. Adjustment of costly extra-group paternity according to inbreeding risk in a cooperative mammal
- Author
-
Michael A. Cant, Jennifer L. Sanderson, and Hazel J. Nichols
- Subjects
Offspring ,mammal ,Biology ,warfare ,QH301 ,Inbreeding depression ,medicine ,mating system ,SF ,Mating ,Ecology, Evolution, Behavior and Systematics ,Genetics ,QL ,Banded mongoose ,Aggression ,Mating system ,biology.organism_classification ,extra-group paternity ,intergroup interaction ,Mate choice ,extrapair paternity ,Animal Science and Zoology ,Original Article ,medicine.symptom ,Inbreeding ,Demography - Abstract
Lay Summary Female-banded mongooses risk their lives to mate with rivals during pack “warfare.” Data from wild banded mongooses reveal that 18% of pups are fathered by males from rival packs. These pups are less likely to be inbred are heavier and have higher survival chances than their within-pack counterparts. However, their mothers risk a lot to mate with extra-pack males; aggressive encounters between packs account for 20% of pup deaths and 12% of adult deaths., Females of many animal species seek mating opportunities with multiple males, despite being able to obtain sufficient sperm to father their offspring from a single male. In animals that live in stable social groups, females often choose to mate outside their group resulting in extra-group paternity (EGP). One reason proposed to explain female choice for extra-group males is to obtain compatible genes, for example, in order to avoid inbreeding depression in offspring. The benefits of such extra-group paternities could be substantial if they result in fitter, outbred offspring. However, avoiding inbreeding in this way could be costly for females, for example, through retaliation by cuckolded males or through receiving aggression while prospecting for extra-group mating opportunities. We investigate the costs and benefits of EGP in the banded mongoose Mungos mungo, a cooperatively breeding mammal in which within-group mates are sometimes close relatives. We find that pups born to females that mate with extra-group males are more genetically heterozygous are heavier and are more likely to survive to independence than pups born to females that mate within their group. However, extra-group matings also involve substantial costs as they occur during violent encounters that sometimes result in injury and death. This appears to lead femalebanded mongooses to adaptively adjust EGP levels according to the current risk of inbreeding associated with mating within the group. For group-living animals, the costs of intergroup interactions may help to explain variation in both inbreeding rates and EGP within and between species.
- Published
- 2015
21. Patterns of helping effort in co‐operatively breeding banded mongooses ( Mungos mungo )
- Author
-
Michael A. Cant
- Subjects
Banded mongoose ,biology ,Offspring ,Ecology ,Kin selection ,biology.organism_classification ,Brood ,Co operation ,Animal Science and Zoology ,Social evolution ,Mungos ,Ecology, Evolution, Behavior and Systematics ,Demography ,Fitness cost - Abstract
In most co-operative breeding species, some individuals contribute much more to helping behaviour than others. The most well-established explanation of such variation is based on kin selection and suggests that, in the absence of detectable differences in relatedness, individuals who suffer lower costs for a given level of help should contribute more. Differences in helping effort between dominance/sex categories were investigated in co-operatively breeding banded mongooses Mungos mungo in Uganda. The most conspicuous form of help in this species is provided by individuals who babysit offspring at the den while the rest of the pack goes off to forage. Across eight groups, the survival rate of pups increased with the average number of babysitters guarding them, consistent with the hypothesis that helpers benefit the brood that they guard. There was no difference between dominant males, subordinate males and breeding females in total contributions to babysitting. Subordinate males, however, contributed more to babysitting in the mornings, which were the longest and presumably the most energetically expensive sessions of the day. In six litters in one well-studied pack, dominant males and breeding females reduced their contribution to babysitting for the period that females were in oestrus. By contrast, subordinate males increased their contribution to become the main babysitters during this time. These results are consistent with the hypothesis that, where helping conflicts with breeding, individuals with little chance of direct reproduction can help at a lower fitness cost than those with a high probability of successful reproduction.
- Published
- 2003
22. Eviction and dispersal in co‐operatively breeding banded mongooses ( Mungos mungo )
- Author
-
Michael A. Cant, Emily Otali, and Francis Mwanguhya
- Subjects
Eviction ,Severe injury ,Banded mongoose ,Ecology ,Aggression ,Biology ,biology.organism_classification ,medicine ,Biological dispersal ,Animal Science and Zoology ,medicine.symptom ,Mungos ,Ecology, Evolution, Behavior and Systematics ,Demography - Abstract
The mode by which individuals disperse, and the cost of dispersal, are of great importance in attempts to understand variation in reproductive skew in animal societies. In this paper we report detailed information on dispersal and pack formation in banded mongooses Mungos mungo. Six pack fission events were recorded among 11 packs over 22 months. Pack fission occurred under two distinct circumstances. First, groups of individuals were evicted from their natal group as a result of intense aggression from other group members. A small fraction of group members was responsible for most of the aggression. Both sexes helped to attack and evict individuals from the group, and both males and females were driven out of their natal groups en masse. The second mode of pack fission occurred when groups of same-sex individuals left their natal group voluntarily to join dispersing individuals of the opposite sex, thereby forming new packs. Dispersing groups were more frequently involved in fights with rival packs of mongooses compared to established groups, and in one instance these fights seemed to be responsible for severe injury and increased mortality among members of a dispersing group. The observations of eviction provide one line of evidence that the presence of subordinates is sometimes detrimental to dominants, contrary to the assumptions of concession models of reproductive skew.
- Published
- 2001
23. Social control of reproduction in banded mongooses
- Author
-
Michael A. Cant
- Subjects
Estrous cycle ,Banded mongoose ,Reproductive suppression ,media_common.quotation_subject ,Gestation period ,Biology ,biology.organism_classification ,Social relation ,Developmental psychology ,Survivorship curve ,Animal Science and Zoology ,Reproduction ,Mating ,Ecology, Evolution, Behavior and Systematics ,Demography ,media_common - Abstract
Recent theoretical work suggests that the distribution of reproduction, or degree of reproductive skew, in animal societies depends crucially on (1) whether dominant individuals can fully control subordinate reproduction, and (2) how subordinate reproduction affects the fitness of dominants. I investigated these two factors in cooperatively breeding banded mongooses, Mungos mungo. Female packmates entered oestrus together and were closely guarded by dominant males. These males were aggressive to subordinate males who attempted to mate, but females still managed to mate with males other than their mate guard. Older females were guarded and mated a few days before their younger packmates, yet all females usually gave birth on the same day, suggesting that older females may have a longer gestation period. Moreover, older females carried more fetuses. Overall, ca. 83% of adult females conceived in each breeding attempt and 71% carried to term. These results indicate that, among males, dominant individuals did not have full control over the mating attempts of subordinates (since they could not fully control the mating behaviour of the females they guarded), while among females there was little or no attempt to prevent subordinates from breeding (at least, prior to parturition). Two within-group infanticides by males suggested that some control over reproduction may be exercised postpartum. Per capita survivorship of young in the den increased with the number of females who gave birth. Thus, dominant females may benefit from subordinate reproduction, providing a possible explanation for the lack of reproductive suppression among females in this species. Copyright 2000 The Association for the Study of Animal Behaviour.
- Published
- 2000
24. Stable isotopes are quantitative indicators of trophic niche.
- Author
-
Marshall, Harry H., Inger, Richard, Jackson, Andrew L., McDonald, Robbie A., Thompson, Faye J., Cant, Michael A., and Young, Hillary
- Subjects
STABLE isotopes ,MONGOOSES - Abstract
Hette‐Tronquart (2019, Ecol. Lett.) raises three concerns about our interpretation of stable isotope data in Sheppard et al. (2018, Ecol. Lett., 21, 665). We feel that these concerns are based on comparisons that are unreasonable or ignore the ecological context from which the data were collected. Stable isotope ratios provide a quantitative indication of, rather than being exactly equivalent to, trophic niche. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
25. Demography and Social Evolution of Banded Mongooses
- Author
-
Emma I. K. Vitikainen, Hazel J. Nichols, and Michael A. Cant
- Subjects
0106 biological sciences ,0303 health sciences ,education.field_of_study ,Banded mongoose ,biology ,Population ,Metapopulation ,Kin selection ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,03 medical and health sciences ,Cooperative breeding ,Biological dispersal ,Social evolution ,education ,Inbreeding ,030304 developmental biology ,Demography - Abstract
Long-term studies of cooperatively breeding vertebrates offer excellent opportunities to test theories about the evolution of cooperation and the demographic consequences of social behavior. Here we draw together over a decade of research on an unusually tractable cooperative mammal system, the banded mongoose (Mungos mungo) and compare our results against advances in social evolution theory that have occurred over the same period. We report recent data on the demographic and genetic structure of the population, and then focus on the main conflictual and cooperative features of the breeding system. Groups are founded by unrelated dispersal coalitions of males and females and consist of multiple male and female breeders. Genetic relatedness between breeding males and females increases with the number of years since group founding, but breeders nevertheless appear to avoid inbreeding. Reproductive competition between females is intense, but young females can escape infanticide by synchronizing birth to the same day as older, socially dominant females. Dominant females respond to reproductive competition by evicting subordinate females en masse. Helping behavior takes two main forms: “babysitting” offspring at the den in the early weeks of life, and “escorting” particular offspring after they emerge from the den. Males contribute most to both babysitting and escorting, particularly the low-ranking males that are excluded from breeding. The way that conflict over reproduction is resolved in this system has a strong influence on patterns of eviction and dispersal. Like many other cooperative vertebrates, each banded mongoose group represents a small, highly viscous population embedded within a larger “metapopulation”. Our research highlights the links between within-group conflict, demography, and the evolution of cooperative life histories.
- Published
- 2013
26. A high‐quality pedigree and genetic markers both reveal inbreeding depression for quality but not survival in a cooperative mammal.
- Author
-
Wells, David A., Cant, Michael A., Nichols, Hazel J., and Hoffman, Joseph I.
- Subjects
- *
BANDED mongoose , *INBREEDING , *COOPERATIVE breeding in animals , *HETEROZYGOSITY , *MICROSATELLITE repeats , *BIOLOGICAL fitness - Abstract
Abstract: Inbreeding depression, the reduced fitness of offspring of closely related parents, is commonplace in both captive and wild populations and has important consequences for conservation and mating system evolution. However, because of the difficulty of collecting pedigree and life‐history data from wild populations, relatively few studies have been able to compare inbreeding depression for traits at different points in the life cycle. Moreover, pedigrees give the expected proportion of the genome that is identical by descent (IBDg) whereas in theory with enough molecular markers realized IBDg can be quantified directly. We therefore investigated inbreeding depression for multiple life‐history traits in a wild population of banded mongooses using pedigree‐based inbreeding coefficients (
f ped) and standardized multilocus heterozygosity (sMLH) measured at 35–43 microsatellites. Within an information theoretic framework, we evaluated support for eitherf ped or sMLH as inbreeding terms and used sequential regression to determine whether the residuals of sMLH onf ped explain fitness variation above and beyondf ped. We found no evidence of inbreeding depression for survival, either before or after nutritional independence. By contrast, inbreeding was negatively associated with two quality‐related traits, yearling body mass and annual male reproductive success. Yearling body mass was associated withf ped but not sMLH, while male annual reproductive success was best explained by bothf ped and residual sMLH. Thus, our study not only uncovers variation in the extent to which different traits show inbreeding depression, but also reveals trait‐specific differences in the ability of pedigrees and molecular markers to explain fitness variation and suggests that for certain traits, genetic markers may capture variation in realized IBDg above and beyond the pedigree expectation. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
27. Resource limitation moderates the adaptive suppression of subordinate breeding in a cooperatively breeding mongoose
- Author
-
Sarah J. Hodge, Hazel J. Nichols, Matthew B.V. Bell, and Michael A. Cant
- Subjects
Social group ,Banded mongoose ,biology ,Reproductive success ,Ecology ,Cooperative breeding ,biology.animal ,Social animal ,Animal Science and Zoology ,biology.organism_classification ,Mungos ,Mongoose ,Ecology, Evolution, Behavior and Systematics - Abstract
Social animal species show considerable variation in the way in which reproduction is distributed among group members. Recent attempts to explain this variation have proposed that differences in reproductive skew are attributable to differences in the net benefits group members receive from suppressing each other’s breeding attempts. Despite receiving relatively little theoretical and empirical attention, the availability of resources required for successful breeding may have an important influence in determining the costs and benefits of suppressing reproduction and thus influence reproductive skew within social groups. Here, we test this possibility using a long-term study of female reproductive success in the banded mongoose Mungos mungo .W e find that females experience greater costs of co-breeding when resources are in short supply and that older, more dominant females respond to this cost by suppressing subordinate breeding. This results in differing patterns of reproductive success for females of different competitive abilities, with the oldest, most dominant females breeding regardless of resource availability and younger, subordinate females breeding only when resources are abundant. Our findings highlight the role of resource limitation in determining the distribution of reproductive opportunities within social groups. Key words: cooperative breeding, dominance, rainfall, reproductive conflict, resource availability, suppression. [Behav Ecol]
- Published
- 2012
28. Reproductive competition and the evolution of extreme birth synchrony in a cooperative mammal
- Author
-
Matthew B.V. Bell, Michael A. Cant, and Sarah J. Hodge
- Subjects
Temporal clustering ,Time Factors ,Offspring ,media_common.quotation_subject ,Competition (biology) ,Reproductive synchrony ,Pregnancy ,medicine ,Animals ,Selection, Genetic ,Social Behavior ,media_common ,Banded mongoose ,biology ,Ecology ,Parturition ,medicine.disease ,biology.organism_classification ,Agricultural and Biological Sciences (miscellaneous) ,Biological Evolution ,Mammal ,Female ,Animal Behaviour ,General Agricultural and Biological Sciences ,Mungos ,Demography - Abstract
Reproductive events in animal societies often show a high degree of temporal clustering, but the evolutionary causes of this synchronization are poorly understood. Here, we suggest that selection to avoid the negative effects of competition with other females has given rise to a remarkable degree of birth synchrony in the communal-breeding banded mongoose ( Mungos mungo ). Within banded mongoose groups, births are highly synchronous, with 64 per cent of females giving birth on exactly the same night. Our results indicate that this extreme synchrony arises because offspring suffer an increased risk of infanticide if their mother gives birth before other females, but suffer in competition with older littermates if their mother gives birth after them. These findings highlight the important influence that reproductive competition can have for the evolution of reproductive synchrony.
- Published
- 2010
29. Reproductive control via eviction (but not the threat of eviction) in banded mongooses
- Author
-
Sarah J. Hodge, Hazel J. Nichols, Jason S. Gilchrist, Matthew B.V. Bell, and Michael A. Cant
- Subjects
punishment ,Punishment (psychology) ,Herpestidae ,QH301 Biology ,Reproduction (economics) ,cooperation ,General Biochemistry, Genetics and Molecular Biology ,Conflict, Psychological ,Sexual Behavior, Animal ,Empirical research ,Game Theory ,Research articles ,skew ,eviction ,Animals ,Uganda ,Social Behavior ,Control (linguistics) ,General Environmental Science ,Pace ,Banded mongoose ,Eviction ,General Immunology and Microbiology ,biology ,Reproduction ,General Medicine ,reproductive conflict ,Models, Theoretical ,biology.organism_classification ,Social Dominance ,Linear Models ,570 Life sciences ,Female ,General Agricultural and Biological Sciences ,Psychology ,Social psychology ,Game theory - Abstract
Considerable research has focused on understanding variation in reproductive skew in cooperative animal societies, but the pace of theoretical development has far outstripped empirical testing of the models. One major class of model suggests that dominant individuals can use the threat of eviction to deter subordinate reproduction (the ‘restraint’ model), but this idea remains untested. Here, we use long-term behavioural and genetic data to test the assumptions of the restraint model in banded mongooses (Mungos mungo), a species in which subordinates breed regularly and evictions are common. We found that dominant females suffer reproductive costs when subordinates breed, and respond to these costs by evicting breeding subordinates from the groupen masse, in agreement with the assumptions of the model. We found no evidence, however, that subordinate females exercise reproductive restraint to avoid being evicted in the first place. This means that the pattern of reproduction is not the result of a reproductive ‘transaction’ to avert the threat of eviction. We present a simple game theoretical analysis that suggests that eviction threats may often be ineffective to induce pre-emptive restraint among multiple subordinates and predicts that threats of eviction (or departure) will be much more effective in dyadic relationships and linear hierarchies. Transactional models may be more applicable to these systems. Greater focus on testing the assumptions rather than predictions of skew models can lead to a better understanding of how animals control each other's reproduction, and the extent to which behaviour is shaped by overt acts versus hidden threats.
- Published
- 2010
30. Explaining negative kin discrimination in a cooperative mammal society.
- Author
-
Thompson, Faye J., Cant, Michael A., Marshall, Harry H., Vitikainen, Emma I. K., Sanderson, Jennifer L., Nichols, Hazel J., Gilchrist, Jason S., Bell, Matthew B. V., Young, Andrew J., Hodge, Sarah J., and Johnstone, Rufus A.
- Subjects
- *
KIN selection (Evolution) , *BANDED mongoose , *SOCIAL behavior in mammals , *GAME theory , *INBREEDING , *ANIMAL behavior - Abstract
Kin selection theory predicts that, where kin discrimination is possible, animals should typically act more favorably toward closer genetic relatives and direct aggression toward less closely related individuals. Contrary to this prediction, we present data from an 18-y study of wild banded mongooses, Mungos mungo, showing that females that are more closely related to dominant individuals are specifically targeted for forcible eviction from the group, often suffering severe injury, and sometimes death, as a result. This pattern cannot be explained by inbreeding avoidance or as a response to more intense local competition among kin. Instead, we use game theory to show that such negative kin discrimination can be explained by selection for unrelated targets to invest more effort in resisting eviction. Consistent with our model, negative kin discrimination is restricted to eviction attempts of older females capable of resistance; dominants exhibit no kin discrimination when attempting to evict younger females, nor do they discriminate between more closely or less closely related young when carrying out infanticidal attacks on vulnerable infants who cannot defend themselves. We suggest that in contexts where recipients of selfish acts are capable of resistance, the usual prediction of positive kin discrimination can be reversed. Kin selection theory, as an explanation for social behavior, can benefit from much greater exploration of sequential social interactions. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
31. Heterozygosity but not inbreeding coefficient predicts parasite burdens in the banded mongoose.
- Author
-
Mitchell, J., Vitikainen, E. I. K., Wells, D. A., Cant, M. A., and Nichols, H. J.
- Subjects
HETEROZYGOSITY ,HALDANE'S rule ,HOMOZYGOSITY ,BANDED mongoose ,CONSANGUINITY - Abstract
Inbreeding, reproduction between relatives, often impinges on the health and survival of resulting offspring. Such inbreeding depression may manifest itself through immunological costs as inbred individuals suffer increased propensity to disease, infection and parasites compared to outbred conspecifics. Here, we assess how the intestinal parasite loads of wild banded mongooses ( Mungos mungo) vary with pedigree inbreeding coefficient (ƒ) and standardized multi-locus heterozygosity. We find a significant association between increased heterozygosity and lower parasite loads; however, this correlation does not stand when considering ƒ. Such findings may be explained by local genetic effects, linkage between genetic markers and genes influencing parasite burdens. Indeed, we find heterozygosity at certain loci to correlate with parasite load. Although these tentative local effects are lost following multiple test correction, they warrant future investigation to determine their strength and impact. We also suggest frequent inbreeding within banded mongooses may mean heterozygosity is a better predictor of inbreeding than pedigree ƒ. This is because inbreeding facilitates linkage disequilibrium, increasing the chances of neutral markers representing genome-wide heterozygosity. Finally, neither ƒ nor heterozygosity had a significant influence on the loads of two specific gastrointestinal parasites. Nevertheless, more heterozygous individuals benefited from reduced overall parasitic infection and genetic diversity appears to explain some variation in parasite burdens in the banded mongoose. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
32. Variable ecological conditions promote male helping by changing banded mongoose group composition.
- Author
-
Marshall, Harry H., Sanderson, Jennifer L., Mwanghuya, Francis, Businge, Robert, Kyabulima, Solomon, Hares, Michelle C., Inzani, Emma, Kalema-Zikusoka, Gladys, Mwesige, Kenneth, Thompson, Faye J., Vitikainen, Emma I. K., and Cant, Michael A.
- Subjects
BANDED mongoose ,ALTRUISTIC behavior in animals ,SURVIVAL behavior (Animals) ,ANIMAL social behavior ,HABITATS ,ANIMAL behavior - Abstract
Ecological conditions are expected to have an important influence on individuals' investment in cooperative care. However, the nature of their effects is unclear: both favorable and unfavorable conditions have been found to promote helping behavior. Recent studies provide a possible explanation for these conflicting results by suggesting that increased ecological variability, rather than changes in mean conditions, promote cooperative care. However, no study has tested whether increased ecological variability promotes individual- level helping behavior or the mechanisms involved. We test this hypothesis in a long-term study population of the cooperatively breeding banded mongoose, Mungos mungo, using 14 years of behavioral and meteorological data to explore how the mean and variability of ecological conditions influence individual behavior, body condition, and survival. Female body condition was more sensitive to changes in rainfall leading to poorer female survival and pronounced male-biased group compositions after periods of high rainfall variability. After such periods, older males invested more in helping behavior, potentially because they had fewer mating opportunities. These results provide the first empirical evidence for increased individual helping effort in more variable ecological conditions and suggest this arises because of individual differences in the effect of ecological conditions on body condition and survival, and the knock-on effect on social group composition. Individual differences in sensitivity to environmental variability, and the impacts this has on the internal structure and composition of animal groups, can exert a strong influence on the evolution and maintenance of social behaviors, such as cooperative care. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. Banded mongooses avoid inbreeding when mating with members of the same natal group.
- Author
-
Sanderson, Jennifer L., Wang, Jinliang, Vitikainen, Emma I. K., Cant, Michael A., and Nichols, Hazel J.
- Subjects
BANDED mongoose ,ANIMAL breeding ,ANIMAL sexual behavior ,ANIMAL communities ,BIOLOGICAL evolution - Abstract
Inbreeding and inbreeding avoidance are key factors in the evolution of animal societies, influencing dispersal and reproductive strategies which can affect relatedness structure and helping behaviours. In cooperative breeding systems, individuals typically avoid inbreeding through reproductive restraint and/or dispersing to breed outside their natal group. However, where groups contain multiple potential mates of varying relatedness, strategies of kin recognition and mate choice may be favoured. Here, we investigate male mate choice and female control of paternity in the banded mongoose ( Mungos mungo), a cooperatively breeding mammal where both sexes are often philopatric and mating between relatives is known to occur. We find evidence suggestive of inbreeding depression in banded mongooses, indicating a benefit to avoiding breeding with relatives. Successfully breeding pairs were less related than expected under random mating, which appeared to be driven by both male choice and female control of paternity. Male banded mongooses actively guard females to gain access to mating opportunities, and this guarding behaviour is preferentially directed towards less closely related females. Guard-female relatedness did not affect the guard's probability of gaining reproductive success. However, where mate-guards are unsuccessful, they lose paternity to males that are less related to the females than themselves. Together, our results suggest that both sexes of banded mongoose use kin discrimination to avoid inbreeding. Although this strategy appears to be rare among cooperative breeders, it may be more prominent in species where relatedness to potential mates is variable, and/or where opportunities for dispersal and mating outside of the group are limited. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
34. Policing of reproduction by hidden threats in a cooperative mammal.
- Author
-
Cant, Michael A., Nichols, Hazel J., Johnstone, Rufus A., and Hodge, Sarah J.
- Subjects
- *
MAMMAL reproduction , *MAMMAL evolution , *INSECT eggs , *BANDED mongoose , *INFANTICIDE in animals - Abstract
The evolution of cooperation in animal and human societies is associated with mechanisms to suppress individual selfishness. In insect societies, queens and workers enforce cooperation by "policing" selfish reproduction by workers. Insect policing typically takes the form of damage limitation after individuals have carried out selfish acts (such as laying eggs). In contrast, human policing is based on the use of threats that deter individuals from acting selfishly in the first place, minimizing the need for damage limitation. Policing by threat could in principle be used to enforce reproductive suppression in animal societies, but testing this idea requires an experimental approach to simulate reproductive transgression and provoke out-of-equilibrium behavior. We carried out an experiment of this kind on a wild population of cooperatively breeding banded mongooses (Mungos mungo) in Uganda. In this species, each group contains multiple female breeders that give birth to a communal litter, usually on the same day. In a 7-y experiment we used contraceptive injections to manipulate the distribution of maternity within groups, triggering hidden threats of infanticide. Our data suggest that older, socially dominant females use the threat of infanticide to deter selfish reproduction by younger females, but that females can escape the threat of infanticide by synchronizing birth to the same day as older females. Our study shows that reproduction in animal societies can be profoundly influenced by threats that remain hidden until they are triggered experimentally. Coercion may thus extend well beyond the systems in which acts of infanticide are common. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. Testing for vocal individual discrimination in adult banded mongooses.
- Author
-
Jansen, D. A. W. A. M., Cant, M. A., and Manser, M. B.
- Subjects
- *
ANIMAL sound production , *MONGOOSES , *ANIMAL social behavior , *SPECIES , *MOTIVATION in animals , *SOCIAL evolution in animals - Abstract
The ability to individually recognize conspecifics is acknowledged as one of the prerequisites for the development of sophisticated social relationships in group-living species. It has been hypothesized that the discrimination of individual identities is crucial for the maintenance of social relationships and cooperation based on repeated interactions, and for the evolution of many social behaviours. Previous studies have shown that the close calls of the cooperatively breeding banded mongoose Mungos mungo are individually distinct. For instance, banded mongoose pups are able to distinguish between close calls of their escort and of a non-escort. In this study, we used playbacks based on the recently proposed violation-of-expectation paradigm and a dominance/age class recognition setup to investigate whether adult banded mongooses use the individual signature of close calls to distinguish among adult group members. We found no evidence that the individual signature in close calls is used to discriminate identity in banded mongooses. Based on the previous work, we suggest that this is not because banded mongooses are incapable of using signatures as a means of individual discrimination, but because the benefits of such discrimination are low. The study highlights the importance of understanding the function of a signal (e.g. the expected response), timing and the biology of the species when designing and performing playback experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
36. Location and group size influence decisions in simulated intergroup encounters in banded mongooses.
- Author
-
Furrer, Roman D., Kyabulima, Solomon, Willems, Erik P., Cant, Michael A., and Manser, Marta B.
- Subjects
BANDED mongoose ,MUNGOS ,COMPETITION (Biology) ,RESOURCE availability (Ecology) ,DECISION making ,ANIMAL behavior - Abstract
In social species that cooperatively defend territories the decision to retreat or attack in contests between groups is likely to depend on ecological and social factors. Previous studies have emphasized the importance of the encounter location or the size of competing groups on the outcome. In addition, the identity of the intruder, whether familiar or stranger, may also play a role. To test whether the same factors affect the resident group's decisions already at the beginning of contests, we simulated intergroup encounters in banded mongooses (Mungos mungo). When spotting rival groups banded mongooses emit “screeching calls” which lead group members to bunch up. With playbacks of these calls, we tested how the groups' response was affected by the following factors: 1) the location of the playback in relation to their territory (exclusive use vs. overlap); 2) the number of resident individuals; and 3) the origin of calls (neighbor vs. stranger) used. Subjects were more likely to approach the loudspeakers and arrive within 1 m of the speakers in the exclusive use zone than in the overlap zone. Moreover, larger groups tended to be more likely to move toward the loudspeakers and were also more likely to arrive there. The origin of calls used in the playbacks did not affect the groups' responses. These findings exemplify the importance of the combined effect of location and group size on group decisions during impending intergroup contest. [ABSTRACT FROM PUBLISHER]
- Published
- 2011
- Full Text
- View/download PDF
37. Reproductive control via eviction (but not the threat of eviction) in banded mongooses.
- Author
-
Michael A. Cant
- Subjects
- *
REGULATION of reproduction , *BANDED mongoose , *BIOLOGICAL variation , *ANIMAL breeding , *SEX (Biology) , *LIFE (Biology) - Abstract
Considerable research has focused on understanding variation in reproductive skew in cooperative animal societies, but the pace of theoretical development has far outstripped empirical testing of the models. One major class of model suggests that dominant individuals can use the threat of eviction to deter subordinate reproduction (the ‘restraint’ model), but this idea remains untested. Here, we use long-term behavioural and genetic data to test the assumptions of the restraint model in banded mongooses (Mungos mungo), a species in which subordinates breed regularly and evictions are common. We found that dominant females suffer reproductive costs when subordinates breed, and respond to these costs by evicting breeding subordinates from the group en masse, in agreement with the assumptions of the model. We found no evidence, however, that subordinate females exercise reproductive restraint to avoid being evicted in the first place. This means that the pattern of reproduction is not the result of a reproductive ‘transaction’ to avert the threat of eviction. We present a simple game theoretical analysis that suggests that eviction threats may often be ineffective to induce pre-emptive restraint among multiple subordinates and predicts that threats of eviction (or departure) will be much more effective in dyadic relationships and linear hierarchies. Transactional models may be more applicable to these systems. Greater focus on testing the assumptions rather than predictions of skew models can lead to a better understanding of how animals control each other's reproduction, and the extent to which behaviour is shaped by overt acts versus hidden threats. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
38. Imitation and Traditions in Wild Banded Mongooses
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Müller, Corsin A. and Cant, Michael A.
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BANDED mongoose , *FORAGING behavior , *SOCIAL learning , *PRIMATES , *MIMICRY (Biology) , *ANIMAL social behavior , *LEARNING in animals , *ANIMAL behavior - Abstract
Summary: Evidence has accumulated in recent years indicating that traditions are not a unique feature of human societies but may be common in primates and some other mammals []. However, most documented cases remain contentious because observational studies of free-living animals suffer from interpretive weaknesses [], whereas social diffusion experiments performed in captivity (e.g., []) may not reflect conditions found in nature []. Here we use experiments under natural conditions to demonstrate that wild banded mongooses (Mungos mungo) pass preferences for one of two possible foraging techniques on to the next generation through contextual imitation. Notably, both techniques coexisted within the same groups and were transmitted concurrently between adults and pups, which form close one-to-one associations during the period of pup dependency. This experimental demonstration of a foraging tradition in wild mammals provides critical evidence to support previous accounts of traditions in nonhuman animals based on distribution patterns of natural behaviors []. Moreover, our data provide the first experimental demonstration of imitation in wild mammals and, contrary to common assumption [], show that social learning need not lead to an increased behavioral homogeneity within groups. [Copyright &y& Elsevier]
- Published
- 2010
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39. Scent marking within and between groups of wild banded mongooses.
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Jordan, N. R., Mwanguhya, F., Kyabulima, S., Rüedi, P., and Cant, M. A.
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TERRITORIAL marking (Animals) ,ANIMAL behavior ,BANDED mongoose ,COMPETITION (Biology) ,ANIMAL defenses ,AGONISTIC behavior in animals - Abstract
Scent marking is commonly described as a territorial behaviour, and scent marks might deter potential intruders from entering occupied areas. Conspecific neighbours present both a reproductive and a territorial threat, thus, determining which, if any, of these threats shapes scent-marking behaviour is difficult. Banded mongooses Mungos mungo provide a rare clear separation between reproductive rivals (found within groups) and territorial rivals (neighbouring groups), because immigration into social groups is extremely rare, and mating occurs almost exclusively within groups. This situation offers an opportunity to assess the relative importance of territorial defence and intra-group competition for mates in shaping scent-marking behaviour. We combined detailed behavioural observations of scent marking, chemical analyses of scent composition and discrimination experiments in the field, and found little evidence for higher rates of scent marking in overlapping areas, a lack of group specificity of scents and a failure of individuals to discriminate between the scents of different groups. Although scent may fulfill some role in territorial demarcation and defence, these results suggest that scent marks and scent-marking patterns are also involved in communicating within social groups. [ABSTRACT FROM AUTHOR]
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- 2010
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40. Conflict within and between groups of cooperative banded mongooses
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Thompson, Faye Jacqueline, Cant, Michael, and Young, Andrew
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599.74 ,conflict ,cooperation ,social evolution ,eviction ,banded mongoose - Abstract
Conflict within and between social groups is a conspicuous feature of cooperative animal societies. Theoretical and empirical research aims to understand the role of within- and between-group conflict in the evolution of cooperative behaviour, but these forms of conflict are rarely studied together. Eviction as a means of within-group conflict resolution can have important implications for the individuals involved, and the wider population through effects on dispersal, gene flow, and population structure. Intergroup conflict, although prevalent in many social species, is relatively understudied outside of humans and chimpanzees, but could play an important role in the evolution of cooperative behaviours. However, currently there is a lack of understanding of the causes and consequences of within- and between-group conflict to be able to draw conclusions on theoretical links to their role in social evolution. In this thesis, I use a wild population of banded mongooses, Mungos mungo, to investigate the causes and consequences of eviction and intergroup conflict in a highly cooperative species. First, I show that eviction in banded mongooses is triggered by reproductive competition in both sexes (Chapter 2). Second, I find that, once the decision to evict has been made, younger females and those older, more closely related females are preferentially evicted (Chapter 3). This surprising result is explained by a theoretical model which shows that, where individuals are capable of resisting eviction, the usual prediction of positive kin discrimination can be reversed. Third, I show that eviction has demographic effects, with consequences for group size and recruitment (Chapter 4). Finally, I show that intergroup conflict is stimulated by intensified resource competition, and that the consequences of intergroup conflict can have measureable costs to both individuals and groups in the long- and short-term (Chapter 5). This work shows that the means of resolving within-group conflict at an individual level can resonate to affect demography and dynamics at higher levels, and that the nature and intensity of intergroup conflict has the potential to influence patterns of cooperation and conflict within groups. I suggest that within- and between-group conflict may often be intimately linked, and that recognising this link could help to advance our conceptual understanding of their role in the evolution of cooperative behaviour.
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- 2016
41. Top males gain high reproductive success by guarding more successful females in a cooperatively breeding mongoose
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Nichols, Hazel J., Amos, William, Cant, Michael A., Bell, Matthew B.V., and Hodge, Sarah J.
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- *
BANDED mongoose , *COOPERATIVE breeding in animals , *INTERSEXUALITY in animals , *ANIMAL sexual behavior , *ANIMAL courtship , *ANIMAL paternity , *REPRODUCTION , *ANIMAL behavior - Abstract
Of key importance for understanding cooperative societies is the way in which reproductive opportunities are distributed among group members. Traditionally, skew has been thought of as a product of intrasexual competition. However, cooperatively breeding species often live in mixed-sex groups, so the behaviour of one sex has the potential to influence skew in the other. We addressed the importance of inter- and intrasexual conflict in determining reproductive skew through a study of paternity sharing in the cooperatively breeding banded mongoose, Mungus mungo. Unlike banded mongoose females, where reproductive skew is low, males exhibited high skew, with 85% of paternities being assigned to the three oldest males in each group. Individual males appeared unable to monopolize reproduction because females come into oestrus in synchrony and mate multiply. Instead, older males increased their success by mate guarding the oldest, most fecund females. Our findings therefore highlight the importance of mate choice in males and reveal the behavioural differences between the sexes that generate reproductive skew. They also emphasize the considerable influence that female behaviour can have on male reproductive skew. [Copyright &y& Elsevier]
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- 2010
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42. Conflict and cooperation in vertebrate societies
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Sanderson, Jennifer Louise and Cant, Michael
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303.6 ,testosterone ,glucocorticoid ,cooperation ,vertebrate ,banded mongoose - Abstract
Within animal societies, individuals often differ greatly in their level of investment in cooperative activities. Individuals are predicted to show high cooperative investment if high levels of relatedness lead to large indirect fitness benefits, or if differences in individual characteristics such as age, sex, rank, or body condition increase the direct fitness benefits of helping. However, individual differences often persist after these differences are controlled for; a residual variation that remains unexplained. Understanding the proximate mechanisms underlying variation in behaviour can give novel insights into the selection pressures shaping behavioural differences. This suggests that a research focus onto the proximate mechanisms underpinning cooperative behaviours is needed to further our understanding of why individuals behave differently within social groups. In this thesis, I address this shortfall in understanding by investigating hormonal variation alongside individual differences in cooperative investment in the banded mongoose (Mungos mungo). Banded mongooses are a highly social carnivore with two highly conspicuous forms of cooperative offspring care that are easily measurable and show large inter-individual variation. In chapter 3, I demonstrate a negative carry-over effect of investment in offspring care in consecutive breeding attempts. I show that this carry-over effect is mediated by variation in glucocorticoid concentrations, which may be attributable to the energetic costs of helping. Glucocorticoids predict investment in offspring care, suggesting that this mechanism may drive inter-individual variation in cooperative investment. In chapter 4, I find evidence for a testosterone mediated trade-off between offspring care and mating effort, which suggests that inter-individual differences may also be driven by variation in the costs of helping attributable to missed mating opportunities. In chapter 5, I use simulated territorial intrusions to show that there is unlikely to be a trade-off between offspring care and territory defence in banded mongoose societies. However, carers and non-carers show a differential physiological response to territorial intrusion, suggesting that there may be a more subtle behavioural trade-off that occurs post-intrusion. In chapter 6, I find evidence for consistent individual differences in both cooperative and competitive behaviours, which suggests that individual differences in adult behaviour may be determined by early-life effects. Individual differences in cooperative investment are positively correlated, suggesting that individuals are not specialised to different cooperative activities, but are consistently either helpful or selfish. Together, these results give insights into the selection pressures shaping individual differences and highlight endocrine research as a valuable tool in understanding the evolution of cooperative societies.
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- 2012
43. Individual and demographic consequences of mass eviction in cooperative banded mongooses.
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Thompson, Faye J., Marshall, Harry H., Vitikainen, Emma I.K., Young, Andrew J., and Cant, Michael A.
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- *
BANDED mongoose , *ANIMAL societies , *ANIMAL social behavior , *MUNGOS , *ANIMAL behavior , *HERPESTIDAE - Abstract
In animal societies, conflict within groups can result in eviction, where individuals are often permanently expelled from their group. To understand the evolution of eviction and its role in the resolution of within-group conflict requires information on the demographic consequences of eviction for individuals and groups. However, such information is usually difficult to obtain because of the difficulty in tracking and monitoring individuals after they are evicted from their natal groups. Here we used a 15-year data set on life history and demography to investigate the consequences of eviction in a tractable cooperatively breeding mammal, the banded mongoose, Mungos mungo . In this species, groups of individuals are periodically evicted en masse and eviction is a primary mechanism by which new groups form in the study population. Following eviction, we found sex differences in dispersal distance: some females established new groups on the study peninsula but males always dispersed away from the study peninsula. Evicted females suffered reduced reproductive success in the year after eviction. For the evicting group, eviction was associated with increased per capita reproductive success for females, suggesting that eviction is successful in reducing reproductive competition. However, eviction was also associated with increased intergroup conflict for the evicting group. Our results suggest that within-group conflict resolution strategies affect group productivity, group interactions and the structure of the population, and hence have fitness impacts that reach beyond the individual evictors and evictees involved in eviction. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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44. Causes and consequences of intergroup conflict in cooperative banded mongooses.
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Thompson, Faye J., Marshall, Harry H., Vitikainen, Emma I.K., and Cant, Michael A.
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MONGOOSES , *INTERGROUP relations , *SOCIAL evolution in animals , *CHIMPANZEE behavior , *BANDED mongoose - Abstract
Conflict between groups is a notable feature of many animal societies. Recent theoretical models suggest that violent intergroup conflict can shape patterns of within-group cooperation. However, despite its prevalence in social species, the adaptive significance of violent intergroup conflict has been little explored outside of humans and chimpanzees, Pan troglodytes . A barrier to current understanding of the role of intergroup conflict in the evolution of social behaviour is a lack of information on the causes and consequences of aggression between groups. Here, we examined the causes and fitness consequences of intergroup conflict in the banded mongoose, Mungos mungo , using a 16-year data set of observed intergroup interactions, life history and behaviour. Banded mongooses are cooperative breeders that live in highly territorial groups and engage in frequent, aggressive and violent intergroup interactions. We found that intensified population-wide competition for food and mates increased the probability of intergroup interactions, and that increased intergroup conflict was associated with periods in which groups were growing in size. Intergroup conflict had fitness costs in terms of reduced litter and adult survival but no cost to pregnant females: in fact, females were less likely to abort following an intergroup interaction than when there had been no recent intergroup conflict. Our results suggest that intergroup conflict has measurable costs to both individuals and groups in the long and short term, and that levels of conflict among groups could be high enough to affect patterns of within-group cooperative behaviour. Establishing the consequences of intergroup conflict in cooperative species can shed light on patterns of conflict and cooperation within groups and, in turn, facilitate our understanding of social evolution. [ABSTRACT FROM AUTHOR]
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- 2017
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45. The origins of consistent individual differences in cooperation in wild banded mongooses, Mungos mungo.
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Sanderson, Jennifer L., Stott, Iain, Young, Andrew J., Vitikainen, Emma I.K., Hodge, Sarah J., and Cant, Michael A.
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- *
INDIVIDUAL differences , *BANDED mongoose , *PHENOTYPES , *ANIMAL societies , *ECOLOGICAL niche , *ANIMAL social behavior , *ANIMAL behavior - Abstract
Individual differences in contributions to cooperation can be strikingly consistent over time giving rise to alternative cooperative phenotypes within animal societies. Following the social niche specialization hypothesis, these consistent differences may be driven by social conflict over reproductive opportunities if individuals specializing as ‘breeders’ and ‘nonbreeders’ experience a beneficial reduction in social conflict and differential costs associated with cooperating. This hypothesis gives three testable predictions: (1) consistent individual differences in cooperative behaviour will be accompanied by consistent individual differences in reproductive behaviour, (2) individuals contributing heavily to reproduction will contribute relatively little to cooperative behaviours within the same breeding attempt and vice versa, and (3) individuals that consistently contribute heavily to reproduction over their lifetime will also consistently contribute less to cooperative behaviours and vice versa. We tested these predictions with a 15-year investigation into the lifetime patterns of mate guarding and two forms of cooperative offspring care (‘babysitting’ and ‘escorting’) in a wild population of banded mongooses. We found significant repeatability of individual contributions to both cooperative behaviours, as well as significant repeatability of individual levels of mate guarding. However, we found no evidence of negative covariance between contributions to cooperative and reproductive behaviours either within breeding attempts or across lifetimes. This suggests that the observed consistent individual differences in both cooperative behaviour and reproduction are not associated; there is no evidence of a trade-off between reproduction and cooperation. However, we found a significant positive covariance between babysitting and escorting when estimated both within breeding attempts and across lifetimes, which suggests that some group members are generally more cooperative than others, contributing more to both behaviours over their lifetimes. The drivers of this consistent individual variation in contributions to cooperation remain unknown. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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46. Scent marking in wild banded mongooses: 3. Intrasexual overmarking in females
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Jordan, Neil R., Mwanguhya, Francis, Kyabulima, Solomon, Rüedi, Peter, Hodge, Sarah J., and Cant, Michael A.
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- *
TERRITORIAL marking (Animals) , *BANDED mongoose , *ANIMAL breeding , *SEXUAL selection , *ANIMAL feeding , *ANIMAL courtship , *ANIMAL communication , *COMPETITION (Biology) , *ANIMAL behavior - Abstract
In contrast to numerous studies of scent marking in male mammals, studies of female scent marking are relatively rare. We have previously shown that communally breeding female banded mongooses, Mungos mungo, are more likely to overmark the scent of other females. Here we describe female overmarking patterns in more detail, and discuss these results in relation to hypotheses potentially explaining such ‘female intrasexual overmarking’. To our knowledge, this is the first study to investigate female overmarking in any wild mammal. First, although we found some evidence of individually distinctive scent marks in females, we found no evidence to suggest that female intrasexual overmarking was related to competition for food, as feeding competition was infrequent, and unrelated to overmarking scores. We also found no evidence to suggest that intrasexual overmarking in females was involved in reproductive suppression. Females with the highest and lowest overmarking scores in each group were mate-guarded by males for similar durations. Finally, we found little evidence to suggest that female intrasexual overmarking was involved in competition for males. Although the female with the highest overmarking score in each group tended to be mate-guarded by males in better condition than the female with the lowest overmarking score, a female’s overmarking score affected neither the amount of harassment she received from males nor the frequency of mating attempts received. These results are discussed in light of these and other untested hypotheses for female overmarking. [Copyright &y& Elsevier]
- Published
- 2011
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47. Scent marking in wild banded mongooses: 2. Intrasexual overmarking and competition between males
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Jordan, Neil R., Mwanguhya, Francis, Furrer, Roman D., Kyabulima, Solomon, Rüedi, Peter, and Cant, Michael A.
- Subjects
- *
TERRITORIAL marking (Animals) , *BANDED mongoose , *SEXUAL selection , *RODENTS , *ANIMAL courtship , *ANIMAL communication , *COMPETITION (Biology) , *ANIMAL behavior ,SEX differences (Biology) - Abstract
Sexual selection has resulted in the elaboration of secondary sexual characteristics in many animals. Although mammalian scent glands, secretions and marking behaviour are commonly sexually dimorphic, these traits have received little attention compared to avian plumage and mammalian weaponry. Overmarking, when one individual places a scent mark directly over that of another individual, is of particular interest. Owing to the costs of repeatedly monitoring and covering the scent marks of rivals, overmarking may provide an honest indication of a male’s resource-holding potential, perhaps explaining why female rodents exposed to experimental overmarks subsequently prefer to associate with males whose scent mark was on top. This study on wild banded mongooses, Mungos mungo, suggests that overmarking may primarily affect behavioural mating success through male competition not by female mate choice. First, chemical analyses of anal gland secretions demonstrated that males had individually distinctive scents, and a field experiment confirmed that mongooses were able to discriminate between scents from different individuals. Observations of overmarking patterns showed a relationship between overmarking score and behavioural mating success, but we found no evidence that females actively chose to mate with males with high overmarking scores. Instead, we found that males with higher overmarking scores first mate-guarded females at a significantly younger age than males with lower overmarking scores. Since mate-guarding males obtain the vast majority of matings, this suggests that overmarking may be an important component of intrasexual competition for mating opportunities in this species. [Copyright &y& Elsevier]
- Published
- 2011
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48. Scent marking in wild banded mongooses: 1. Sex-specific scents and overmarking
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Jordan, Neil R., Manser, Marta B., Mwanguhya, Francis, Kyabulima, Solomon, Rüedi, Peter, and Cant, Michael A.
- Subjects
- *
TERRITORIAL marking (Animals) , *BANDED mongoose , *SEXUAL selection , *ANIMAL young , *ANIMAL communication , *SEXUAL orientation , *SMELL , *COMPETITION (Biology) , *ANIMAL behavior ,SEX differences (Biology) - Abstract
Overmarking occurs when one individual places its scent mark directly on top of the scent mark of another individual. Although it is almost ubiquitous among terrestrial mammals, we know little about the function of overmarking and detailed field observations are rare. We investigated the chemical composition of scents and patterns of overmarking by wild banded mongooses, Mungos mungo. Chemical analyses of anal gland secretions showed that scents were sexually dimorphic. Both male and female adults were more likely to overmark the scents of same-sex individuals. An analysis of responses to two scents on the same site suggested that the sex of the top or most recent scent was more important than that of the bottom or original scent in determining overmarking response. Juveniles also overmarked scents at high rates, but did not respond to scents in a sex-specific way. Same-sex-specific patterns within groups have not been described in any other species, and may reflect a social system with intense intrasexual competition for reproduction within both sexes. Banded mongooses live in large mixed-sex groups, with intense competition between males for females, owing to the heavily male-biased adult sex ratio and highly synchronized oestrous cycles. Oestrous synchronization may also promote intrasexual competition for males within females, as females compete simultaneously for high-quality males. Female competition for males may also be enhanced by the rewards of male-biased parental care. This investigation highlights the need for detailed studies of overmarking in the natural context, to confirm and expand upon laboratory findings. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
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