1
|
Majelantle TL, Ganswindt A, Hart DW, Hagenah N, Ganswindt SB, Bennett NC. The dissection of a despotic society: exploration, dominance and hormonal traits. Proc Biol Sci 2024; 291:20240371. [PMID: 38714210 PMCID: PMC11095815 DOI: 10.1098/rspb.2024.0371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 03/27/2024] [Accepted: 03/27/2024] [Indexed: 05/09/2024] Open
Abstract
Naked mole-rats (Heterocephalus glaber) live in large colonies with one breeding female (queen), one to three breeding males (BMs) and the remainder are non-reproductive subordinates. The animals have a linear dominance rank with the breeders at the top of the hierarchy. We investigated how dominance rank in naked mole-rats differs with exploration (the propensity to explore a novel environment) and related endocrine markers. Exploration behaviour, faecal progestagen metabolite (fPM), faecal glucocorticoid metabolite (fGCM), faecal androgen metabolite (fAM) and plasma prolactin concentrations were quantified in breeding, high-, middle- and low-ranked females and males from five naked mole-rat colonies. There were no significant differences between the dominance rank and exploration behaviour. Interestingly, the queens and high-ranking females had higher fGCM and fAM concentrations compared with middle- and low-ranked females. The queens had significantly higher fPM concentrations than all other ranked females, since they are responsible for procreation. In the males, the BMs had higher fGCM concentrations compared with high- and low-ranked males. In addition, BMs and middle-ranking males had overall higher prolactin levels than all other ranked males, which could be linked to cooperative care. Overall, the results suggest that physiological reproductive suppression is linked to high dominance rank.
Collapse
Affiliation(s)
- Tshepiso Lesedi Majelantle
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| | - Andre Ganswindt
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| | - Daniel William Hart
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| | - Nicole Hagenah
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| | - Stefanie Birgit Ganswindt
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| | - Nigel Charles Bennett
- Department of Zoology and Entomology, Mammal Research Institute, University of Pretoria, Pretoria, 400364, South Africa
| |
Collapse
|
2
|
Hatton IA, Mazzarisi O, Altieri A, Smerlak M. Diversity begets stability: Sublinear growth and competitive coexistence across ecosystems. Science 2024; 383:eadg8488. [PMID: 38484074 DOI: 10.1126/science.adg8488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 02/07/2024] [Indexed: 03/19/2024]
Abstract
The worldwide loss of species diversity brings urgency to understanding how diverse ecosystems maintain stability. Whereas early ecological ideas and classic observations suggested that stability increases with diversity, ecological theory makes the opposite prediction, leading to the long-standing "diversity-stability debate." Here, we show that this puzzle can be resolved if growth scales as a sublinear power law with biomass (exponent <1), exhibiting a form of population self-regulation analogous to models of individual ontogeny. We show that competitive interactions among populations with sublinear growth do not lead to exclusion, as occurs with logistic growth, but instead promote stability at higher diversity. Our model realigns theory with classic observations and predicts large-scale macroecological patterns. However, it makes an unsettling prediction: Biodiversity loss may accelerate the destabilization of ecosystems.
Collapse
Affiliation(s)
- Ian A Hatton
- Max Planck Institute for Mathematics in the Sciences, 04103 Leipzig, Germany
- Department of Earth and Planetary Sciences, McGill University, Montreal, QC H3A 0E8, Canada
| | - Onofrio Mazzarisi
- Max Planck Institute for Mathematics in the Sciences, 04103 Leipzig, Germany
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
- The Abdus Salam International Centre for Theoretical Physics (ICTP), 34014 Trieste, Italy
- National Institute of Oceanography and Applied Geophysics (OGS), 34014 Trieste, Italy
| | - Ada Altieri
- Laboratoire Matière et Systèmes Complexes (MSC), Université Paris Cité CNRS, 75013 Paris, France
| | - Matteo Smerlak
- Max Planck Institute for Mathematics in the Sciences, 04103 Leipzig, Germany
- Laboratoire de Biophysique et Evolution, UMR 8231 CBI, ESPCI Paris, PSL Research University, 75005 Paris, France
- Capital Fund Management, 75007 Paris, France
| |
Collapse
|
3
|
Duncan C, Thorley J, Manser MB, Clutton-Brock T. Dominance loss and tenure maintenance in Kalahari meerkats. Behav Ecol 2023; 34:979-991. [PMID: 37969548 PMCID: PMC10636735 DOI: 10.1093/beheco/arad066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 07/10/2023] [Accepted: 07/31/2023] [Indexed: 11/17/2023] Open
Abstract
In many social species, both the acquisition of dominance and the duration that individuals maintain their status are important determinants of breeding tenure and lifetime reproductive success. However, few studies have yet examined the extent and causes of variation in dominance tenure and the duration of breeding lifespans. Here, we investigate the processes that terminate dominance tenures and examine how they differ between the sexes in wild Kalahari meerkats (Suricata suricatta), a cooperative breeder where a dominant breeding pair produces most of the young recruited into each group. Mortality and displacement by resident subordinate competitors were important forms of dominance loss for both sexes. However, dominant males (but rarely females) were also at risk of takeovers by extra-group invading males. Dominant males also differed from dominant females in that they abandoned their group after the death of their breeding partner, when no other breeding opportunities were present, whereas dominant females that lost their partner remained and continued to breed in the same group. We show that a larger number of processes can terminate dominance tenure in males with the result that the average male tenure of breeding positions was shorter than that of females, which contributes to the reduced variance in the lifetime reproductive success in males compared to females. Our analysis suggests that sex differences in emigration and immigration may often have downstream consequences for sex differences in reproductive variance and for the selection pressures operating on females and males.
Collapse
Affiliation(s)
- Chris Duncan
- Large Animal Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
- Kalahari Research Centre, Kuruman River Reserve, Northern Cape 8467, South Africa
| | - Jack Thorley
- Large Animal Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
- Kalahari Research Centre, Kuruman River Reserve, Northern Cape 8467, South Africa
| | - Marta B Manser
- Kalahari Research Centre, Kuruman River Reserve, Northern Cape 8467, South Africa
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Mammal Research Institute, University of Pretoria, 0028 Pretoria, South Africa
| | - Tim Clutton-Brock
- Large Animal Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
- Kalahari Research Centre, Kuruman River Reserve, Northern Cape 8467, South Africa
- Mammal Research Institute, University of Pretoria, 0028 Pretoria, South Africa
| |
Collapse
|
4
|
Rotics S, Groenewoud F, Manser M, Clutton-Brock T. Pregnancy reduces concurrent pup care behaviour in meerkats, generating differences between dominant and subordinate females. J Anim Ecol 2023; 92:1431-1441. [PMID: 37277989 DOI: 10.1111/1365-2656.13963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 04/19/2023] [Indexed: 06/07/2023]
Abstract
In some mammals, and particularly in cooperative breeding ones, successive bouts of reproduction can overlap so that a female is often pregnant while still nurturing dependent young from her previous litter. Such an overlap requires females to divide their energetic budget between two reproductive activities, and pregnancy costs would consequently be expected to reduce investment in concurrent offspring care. However, explicit evidence for such reductions is scarce, and the potential effects they may have on work division in cooperative breeders have not been explored. Using 25 years of data on reproduction and cooperative behaviour in wild Kalahari meerkats, supplemented with field experiments, we investigated whether pregnancy reduces contributions to cooperative pup care behaviours, including babysitting, provisioning and raised guarding. We also explored whether pregnancy, which is more frequent in dominants than subordinates, could account for the reduced contributions of dominants to the cooperative pup care behaviours. We found that pregnancy, particularly at late stages of gestation, reduces contributions to cooperative pup care; that these reductions are eliminated when the food available to pregnant females is experimentally supplemented; and that pregnancy effects accounted for differences between dominants and subordinates in two of the three cooperative behaviours examined (pup provisioning and raised guarding but not babysitting). By linking pregnancy costs with reductions in concurrent pup care, our findings illuminate a trade-off between investment in successive, overlapping bouts of reproduction. They also suggest that some of the differences in cooperative behaviour between dominant and subordinate females in cooperative breeding mammals can be a direct consequence of differences in their breeding frequency.
Collapse
Affiliation(s)
- Shay Rotics
- School of Zoology, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, Israel
- The Steinhardt Museum of Natural History, Tel-Aviv University, Tel Aviv, Israel
- Department of Zoology, University of Cambridge, Cambridge, UK
| | | | - Marta Manser
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Kalahari Research Centre, Kuruman River Reserve, Van Zylsrus, South Africa
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, UK
- Kalahari Research Centre, Kuruman River Reserve, Van Zylsrus, South Africa
- Department of Zoology, Mammal Research Institute, University of Pretoria, RSA, Pretoria, South Africa
| |
Collapse
|
5
|
Péron G. Reproductive skews of territorial species in heterogeneous landscapes. OIKOS 2022. [DOI: 10.1111/oik.09627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
6
|
Braga Goncalves I, Radford AN. Experimental evidence that chronic outgroup conflict reduces reproductive success in a cooperatively breeding fish. eLife 2022; 11:72567. [PMID: 36102799 PMCID: PMC9473690 DOI: 10.7554/elife.72567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Conflicts with conspecific outsiders are common in group-living species, from ants to primates, and are argued to be an important selective force in social evolution. However, whilst an extensive empirical literature exists on the behaviour exhibited during and immediately after interactions with rivals, only very few observational studies have considered the cumulative fitness consequences of outgroup conflict. Using a cooperatively breeding fish, the daffodil cichlid (Neolamprologus pulcher), we conducted the first experimental test of the effects of chronic outgroup conflict on reproductive investment and output. ‘Intruded’ groups received long-term simulated territorial intrusions by neighbours that generated consistent group-defence behaviour; matched ‘Control’ groups (each the same size and with the same neighbours as an Intruded group) received no intrusions in the same period. Intruded groups had longer inter-clutch intervals and produced eggs with increasingly less protein than Control groups. Despite the lower egg investment, Intruded groups provided more parental care and achieved similar hatching success to Control groups. Ultimately, however, Intruded groups had fewer and smaller surviving offspring than Control groups at 1-month post-hatching. We therefore provide experimental evidence that outgroup conflict can decrease fitness via cumulative effects on reproductive success, confirming the selective potential of this empirically neglected aspect of sociality.
Collapse
Affiliation(s)
| | - Andrew N Radford
- School of Biological Sciences/Life Sciences, University of Bristol
| |
Collapse
|
7
|
Drea CM, Davies CS. Meerkat manners: Endocrine mediation of female dominance and reproductive control in a cooperative breeder. Horm Behav 2022; 145:105245. [PMID: 35988450 DOI: 10.1016/j.yhbeh.2022.105245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/18/2022] [Accepted: 08/08/2022] [Indexed: 11/16/2022]
Abstract
This article is part of a Special Issue (Hormones and Hierarchies). To gain more balanced understanding of sexual selection and mammalian sexual differentiation processes, this review addresses behavioral sex differences and hormonal mediators of intrasexual competition in the meerkat (Suricata suricatta) - a cooperative breeder unusual among vertebrates in its female aggression, degree of reproductive skew, and phenotypic divergence. Focused on the evolution, function, mechanism, and development of female dominance, the male remains a key reference point throughout. Integrated review of endocrine function does not support routine physiological suppression in subordinates of either sex, but instead a ramp up of weight, reproduction, aggression, and sex steroids, particularly androgens, in dominant females. Important and timely questions about female competition are thus addressed by shifting emphasis from mediators of reproductive suppression to mediators of reproductive control, and from organizational and activational roles of androgens in males to their roles in females. Unusually, we ask not only how inequity is maintained, but how dominance is acquired within a lifetime and across generations. Antiandrogens administered in the field to males and pregnant dominant females confirm the importance of androgen-mediated food competition. Moreover, effects of maternal endocrine milieu on offspring development reveal a heritable, androgenic route to female aggression, likely promoting reproductive priority along dominant matrilines. Integrating endocrine measures with long-term behavioral, ecological, morphological, and life-history data on normative and experimental individuals, across life stages and generations, provides better appreciation of the role of naturally circulating androgens in regulating the female phenotype, and sheds new light on the evolution of female dominance, reproductive inequity, and cooperative breeding.
Collapse
Affiliation(s)
- Christine M Drea
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708-0383, USA; Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa.
| | - Charli S Davies
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708-0383, USA; Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa
| |
Collapse
|
8
|
Averly B, Sridhar VH, Demartsev V, Gall G, Manser M, Strandburg-Peshkin A. Disentangling influence over group speed and direction reveals multiple patterns of influence in moving meerkat groups. Sci Rep 2022; 12:13844. [PMID: 35974046 PMCID: PMC9381760 DOI: 10.1038/s41598-022-17259-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 07/22/2022] [Indexed: 11/25/2022] Open
Abstract
Animals that travel together in groups must constantly come to consensus about both the direction and speed of movement, often simultaneously. Contributions to collective decisions may vary among group members, yet inferring who has influence over group decisions is challenging, largely due to the multifaceted nature of influence. Here we collected high-resolution GPS data from five habituated meerkat groups in their natural habitat during foraging and developed a method to quantify individual influence over both group direction and speed. We find that individual influence over direction and speed are correlated, but also exhibit substantial variation. Comparing patterns across social statuses reveals that dominant females have higher influence than other individuals over both group direction and speed. Individuals with high influence also tend to spend more time in the front of the group. We discuss our results in light of meerkat life-history and current literature on influence during group movement. Our method provides a general approach which can be applied to disentangle individual influence over group direction and speed in a wide range of species with cohesive movement, emphasizing the importance of integrating multiple lines of inquiry when inferring influence in moving animal groups.
Collapse
Affiliation(s)
- Baptiste Averly
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Constance, Germany.,Department of Biology, University of Konstanz, Constance, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Constance, Germany.,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa
| | - Vivek H Sridhar
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Constance, Germany.,Department of Biology, University of Konstanz, Constance, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Constance, Germany
| | - Vlad Demartsev
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Constance, Germany.,Department of Biology, University of Konstanz, Constance, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Constance, Germany.,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Gabriella Gall
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Constance, Germany.,Department of Biology, University of Konstanz, Constance, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Constance, Germany.,Zukunftskolleg, University of Konstanz, Constance, Germany
| | - Marta Manser
- Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Ariana Strandburg-Peshkin
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Constance, Germany. .,Department of Biology, University of Konstanz, Constance, Germany. .,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Constance, Germany. .,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa. .,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
9
|
Braga Goncalves I, Morris-Drake A, Kennedy P, Radford AN. Fitness consequences of outgroup conflict. eLife 2022; 11:e74550. [PMID: 35833830 PMCID: PMC9282852 DOI: 10.7554/elife.74550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 06/27/2022] [Indexed: 12/13/2022] Open
Abstract
In social species across the animal kingdom, conspecific outsiders threaten the valuable resources of groups and their members. This outgroup conflict is recognised as a powerful selection pressure, but we argue that studies explicitly quantifying the fitness consequences need to be broader in scope: more attention should be paid to delayed, cumulative, and third-party fitness consequences, not just those arising immediately to group members involved in physical contests. In the first part of this review, we begin by documenting how single contests can have survival and reproductive consequences either immediately or with a delay. Then, we step beyond contests to describe fitness consequences that can also result from interactions with cues of rival presence and the general landscape of outgroup threat, and beyond single interactions to describe cumulative effects of territorial pressure and elevated outgroup-induced stress. Using examples from a range of taxa, we discuss which individuals are affected negatively and positively, considering both interaction participants and third-party group members of the same or the next generation. In the second part of the review, we provide suggestions about how to move forward. We highlight the importance of considering how different types of outgroup conflict can generate different selection pressures and of investigating variation in fitness consequences within and between species. We finish by discussing the value of theoretical modelling and long-term studies of natural populations, experimental manipulations, and meta-analyses to develop further our understanding of this crucial aspect of sociality.
Collapse
Affiliation(s)
| | - Amy Morris-Drake
- School of Biological Sciences, University of BristolBristolUnited Kingdom
| | - Patrick Kennedy
- School of Biological Sciences, University of BristolBristolUnited Kingdom
| | - Andrew N Radford
- School of Biological Sciences, University of BristolBristolUnited Kingdom
| |
Collapse
|
10
|
Montana L, King WJ, Coulson G, Garant D, Festa-Bianchet M. Large eastern grey kangaroo males are dominant but do not monopolize matings. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-022-03185-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
11
|
Patterson SJ, Clutton-Brock TH, Pfeiffer DU, Drewe JA. Trait-Based Vaccination of Individual Meerkats (Suricata suricatta) against Tuberculosis Provides Evidence to Support Targeted Disease Control. Animals (Basel) 2022; 12:ani12020192. [PMID: 35049814 PMCID: PMC8772857 DOI: 10.3390/ani12020192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 12/14/2022] Open
Abstract
Simple Summary There is evidence to show that, within a population, some individuals are more likely to spread infections than others. When trying to protect a population against infection, most strategies aim to vaccinate as many individuals as possible. However, vaccinating wildlife is difficult because individuals are difficult to find and capture. For wildlife therefore, the ideal strategy would involve targeting vaccinations at those individuals most likely to transmit infection, thus gaining maximum benefit from capturing a small number of individuals. Whilst this seems a very attractive solution, very few studies have attempted to provide evidence to support this theory. This study focuses on a population of meerkats with a history of tuberculosis. Previous work has suggested that socially dominant individuals are most likely to transmit infection, with subordinates most likely to become infected. Therefore, whilst some social groups were left untreated as a baseline, in others, either dominants or subordinates were vaccinated. All groups were monitored for two years, after which time the infection data was analysed. Groups in which vaccinations had been used showed reduced infection rates suggesting that the targeted approach had reduced transmission. A targeted approach may therefore offer an efficient option for vaccinating wildlife in the future. Abstract Individuals vary in their potential to acquire and transmit infections, but this fact is currently underexploited in disease control strategies. We trialled a trait-based vaccination strategy to reduce tuberculosis in free-living meerkats by targeting high-contact meerkats (socially dominant individuals) in one study arm, and high-susceptibility individuals (young subordinates) in a second arm. We monitored infection within vaccinated groups over two years comparing the results with untreated control groups. Being a member of a high-contact group had a protective effect on individuals’ survival times (Hazard Ratio = 0.5, 95% Confidence Interval, CI: 0.29–0.88, p = 0.02) compared to control groups. Over the study, odds of testing positive for tuberculosis increased more than five-fold in control groups (Odds Ratio = 5.40, 95% CI = 0.94–30.98, p = 0.058); however, no increases were observed in either of the treatment arms. Targeted disease control approaches, such as the one described in this study, allow for reduced numbers of interventions. Here, trait-based vaccination was associated with reduced infection rates and thus has the potential to offer more efficient alternatives to traditional mass-vaccination policies. Such improvements in efficiency warrant further study and could make infectious disease control more practically achievable in both animal (particularly wildlife) and human populations.
Collapse
Affiliation(s)
- Stuart J. Patterson
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield, Hertfordshire AL9 7TA, UK; (D.U.P.); (J.A.D.)
- Correspondence:
| | - Tim H. Clutton-Brock
- Large Animal Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK;
- Mammal Research Institute, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Dirk U. Pfeiffer
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield, Hertfordshire AL9 7TA, UK; (D.U.P.); (J.A.D.)
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong, China
| | - Julian A. Drewe
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield, Hertfordshire AL9 7TA, UK; (D.U.P.); (J.A.D.)
| |
Collapse
|
12
|
Saraux C, Chiaradia A. Age‐related breeding success in little penguins: a result of selection and ontogenetic changes in foraging and phenology. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Claire Saraux
- DEPE UMR7178 IPHC CNRS‐Université de Strasbourg 23 rue du Loess 67037 Strasbourg France
| | - Andre Chiaradia
- Conservation Department Phillip Island Nature Parks PO Box 97 Cowes Victoria 3922 Australia
| |
Collapse
|
13
|
A fat chance of survival: Body condition provides life-history dependent buffering of environmental change in a wild mammal population. CLIMATE CHANGE ECOLOGY 2021. [DOI: 10.1016/j.ecochg.2021.100022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
14
|
Duncan C, Manser MB, Clutton‐Brock T. Decline and fall: The causes of group failure in cooperatively breeding meerkats. Ecol Evol 2021; 11:14459-14474. [PMID: 34765119 PMCID: PMC8571573 DOI: 10.1002/ece3.7655] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/15/2021] [Accepted: 02/28/2021] [Indexed: 12/30/2022] Open
Abstract
In many social vertebrates, variation in group persistence exerts an important effect on individual fitness and population demography. However, few studies have been able to investigate the failure of groups or the causes of the variation in their longevity. We use data from a long-term study of cooperatively breeding meerkats, Suricata suricatta, to investigate the different causes of group failure and the factors that drive these processes. Many newly formed groups failed within a year of formation, and smaller groups were more likely to fail. Groups that bred successfully and increased their size could persist for several years, even decades. Long-lived groups principally failed in association with the development of clinical tuberculosis, Mycobacterium suricattae, a disease that can spread throughout the group and be fatal for group members. Clinical tuberculosis was more likely to occur in groups that had smaller group sizes and that had experienced immigration.
Collapse
Affiliation(s)
- Chris Duncan
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
| | - Marta B. Manser
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
- Animal BehaviourDepartment of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
| | - Tim Clutton‐Brock
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
- Mammal Research InstituteUniversity of PretoriaPretoriaSouth Africa
| |
Collapse
|
15
|
Houslay TM, Nielsen JF, Clutton-Brock TH. Contributions of genetic and nongenetic sources to variation in cooperative behavior in a cooperative mammal. Evolution 2021; 75:3071-3086. [PMID: 34647327 DOI: 10.1111/evo.14383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 08/17/2021] [Accepted: 09/30/2021] [Indexed: 11/29/2022]
Abstract
The evolution of cooperative behavior is a major area of research among evolutionary biologists and behavioral ecologists, yet there are few estimates of its heritability or its evolutionary potential, and long-term studies of identifiable individuals are required to disentangle genetic and nongenetic components of cooperative behavior. Here, we use long-term data on over 1800 individually recognizable wild meerkats (Suricata suricatta) collected over 30 years and a multigenerational genetic pedigree to partition phenotypic variation in three cooperative behaviors (babysitting, pup feeding, and sentinel behavior) into individual, additive genetic, and other sources, and to assess their repeatability and heritability. In addition to strong effects of sex, age, and dominance status, we found significant repeatability in individual contributions to all three types of cooperative behavior both within and across breeding seasons. Like most other studies of the heritability of social behavior, we found that the heritability of cooperative behavior was low. However, our analysis suggests that a substantial component of the repeatable individual differences in cooperative behavior that we observed was a consequence of additive genetic variation. Our results consequently indicate that cooperative behavior can respond to selection, and suggest scope for further exploration of the genetic basis of social behavior.
Collapse
Affiliation(s)
- Thomas M Houslay
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom.,Kuruman River Reserve, Kalahari Research Centre, Van Zylsrus, 8467, South Africa
| | - Johanna F Nielsen
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JT, United Kingdom
| | - Tim H Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom.,Kuruman River Reserve, Kalahari Research Centre, Van Zylsrus, 8467, South Africa.,Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, 0028, South Africa
| |
Collapse
|
16
|
Dominance hierarchy and social network in a captive group of white-lipped peccary males: what happens after the alpha male leaves? Acta Ethol 2021. [DOI: 10.1007/s10211-021-00386-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
17
|
Abstract
[Figure: see text].
Collapse
|
18
|
Spence‐Jones HC, Brehm AM, Cram D, Gaynor D, Thorley J, Manser MB, Clutton‐Brock TH. Deferred benefits of dominance for natal males in a cooperative breeder, the Kalahari meerkat. J Zool (1987) 2021. [DOI: 10.1111/jzo.12918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- H. C. Spence‐Jones
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
| | - A. M. Brehm
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
| | - D. Cram
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
- Department of Zoology University of Cambridge Cambridge UK
| | - D. Gaynor
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
- Mammal Research Institute University of Pretoria Pretoria South Africa
| | - J. Thorley
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
- Department of Zoology University of Cambridge Cambridge UK
| | - M. B. Manser
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
- Mammal Research Institute University of Pretoria Pretoria South Africa
- Animal Behaviour Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - T. H. Clutton‐Brock
- Kalahari Research Centre Kuruman River Reserve Northern Cape South Africa
- Department of Zoology University of Cambridge Cambridge UK
- Mammal Research Institute University of Pretoria Pretoria South Africa
| |
Collapse
|
19
|
Mutwill AM, Schielzeth H, Zimmermann TD, Richter SH, Kaiser S, Sachser N. Individuality meets plasticity: Endocrine phenotypes across male dominance rank acquisition in guinea pigs living in a complex social environment. Horm Behav 2021; 131:104967. [PMID: 33862349 DOI: 10.1016/j.yhbeh.2021.104967] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 11/28/2022]
Abstract
The time of dominance rank acquisition is a crucial phase in male life history that often affects reproductive success and hence fitness. Hormones such as testosterone and glucocorticoids can influence as well as be affected by this process. At the same time, hormone concentrations can show large individual variation. The extent to which such variation is repeatable, particularly in dynamic social settings, is a question of current interest. The aim of the present study was therefore to investigate how dominance rank and individual differences contribute to variance in hormone concentrations during male rank acquisition in a complex social environment. For this purpose, dominance rank as well as baseline testosterone, baseline cortisol, and cortisol responsiveness after exposure to a novel environment were determined in colony-housed guinea pig males from late adolescence through adulthood. Hormone-dominance relationships and repeatability of hormone measures beyond their relation to rank were assessed. There was a significant positive relationship between baseline testosterone and rank, but this link became weaker with increasing age. Baseline cortisol or cortisol responsiveness, in contrast, were not significantly related to dominance. Notably, all three endocrine parameters were significantly repeatable independent of dominance rank from late adolescence through adulthood. Baseline testosterone and cortisol responsiveness showed a significantly higher repeatability than baseline cortisol. This suggests that testosterone titres and cortisol responsiveness represent stable individual attributes even under complex social conditions.
Collapse
Affiliation(s)
- Alexandra M Mutwill
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149 Münster, Germany; Münster Graduate School of Evolution, University of Münster, Hüfferstr. 1a, 48149 Münster, Germany.
| | - Holger Schielzeth
- Population Ecology Group, Institute of Ecology, Friedrich Schiller University, Dornburgerstr. 159, 07743 Jena, Germany
| | - Tobias D Zimmermann
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149 Münster, Germany
| | - S Helene Richter
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149 Münster, Germany; Münster Graduate School of Evolution, University of Münster, Hüfferstr. 1a, 48149 Münster, Germany
| | - Sylvia Kaiser
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149 Münster, Germany; Münster Graduate School of Evolution, University of Münster, Hüfferstr. 1a, 48149 Münster, Germany
| | - Norbert Sachser
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149 Münster, Germany; Münster Graduate School of Evolution, University of Münster, Hüfferstr. 1a, 48149 Münster, Germany
| |
Collapse
|
20
|
Rotics S, Clutton-Brock T. Group size increases inequality in cooperative behaviour. Proc Biol Sci 2021; 288:20202104. [PMID: 33593194 DOI: 10.1098/rspb.2020.2104] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In cooperatively breeding species where rearing effort is shared among multiple group members, increases in group size typically reduce average per capita contributions to offspring care by all group members (load-lightening) but it is not known how changes in group size affect the distribution of workload among group members. The socioeconomic collective action theory suggests that, in larger groups, the incentives for free riding are stronger, leading to greater inequalities in work division among group members. Here, we use the Gini index to measure inequality at the group level in the contributions of helpers to three different cooperative behaviours (babysitting, pup-provisioning and raised guarding) in groups of varying size in wild Kalahari meerkats (Suricata suricatta). In larger groups, inequality in helpers' contributions to cooperative activities and the frequency of free riding both increased. Elevated levels of inequality were generated partly as a result of increased differences in contributions to cooperative activities between helpers in different sex and age categories in larger groups. After controlling for the positive effect of group size on total provisioning, increasing levels of inequality in contributions were associated with reductions in total pup-provisioning conducted by the group. Reductions in total pup-provisioning were, in turn, associated with reductions in the growth and survival of pups (but pup growth and survival were not directly affected by inequality in provisioning). Our results support the prediction of collective action theory described above and show how the Gini index can be used to investigate the distribution of cooperative behaviour within the group.
Collapse
Affiliation(s)
- Shay Rotics
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Kalahari Research Centre, Kuruman River Reserve, Van Zylsrus 8467, Republic of South Africa
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Kalahari Research Centre, Kuruman River Reserve, Van Zylsrus 8467, Republic of South Africa.,Mammal Research Institute, Department of Zoology, University of Pretoria, Republic of South Africa
| |
Collapse
|
21
|
Silvatti B, Granato TM, Jorge-Neto PN, Luppi MMCP, Reisfeld LC, Henrique PC, Padilha FLA, Leite RF, Losano JDDA, Kawai GKV, Nichi M, Pizzutto CS. Sperm evaluation and morphological description of male genitalia of meerkats (Suricata suricatta). Anim Reprod Sci 2020; 221:106585. [PMID: 32889408 DOI: 10.1016/j.anireprosci.2020.106585] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 02/06/2023]
Abstract
In ex situ conditions, little is known about the reproductive biology of meerkats. The aim of present study was to describe the morphological aspects of male genital organs and accessory glands using macroscopic evaluation, ultrasonography, and radiography, as well as describing semen characteristics post-electroejaculation. The results indicated anatomical characteristics of meerkats are very similar to those of cats, having a prostate, accessory bulbourethral glands, and an elongated and radiopaque structure in the penis, which is indicative of there being a baculum. The testicular volume was 0.81 cm³ (± 0.10) and the relative testis weight was 1.37 cm³/kg (± 0.15). Both testicles are present in the scrotum, which has an ellipsoidal shape, homogeneous texture, hypoechoic parenchyma and are encased in a hyperechoic tunica albuginea. Electroejaculation was effectively induced in all animals for semen collection with utilization of medetomidine and ketamine. The values semen samples variables were as follows for volume - 0.125 ± 0.193 mL, motility - 19.8 ± 18.6 %, vigor - 1.9 ± 1.0, concentration - 40.5 ± 25.2 × 106 sperm/mL and morphologically normal sperm - 10.8 ± 6.6 %. This is the first study in which there is a description of morphological and imaging aspects of the male reproductive tracts of meerkats, as well as the seminal characteristics after using electroejaculation for semen collection. Knowledge of anatomical and seminal characteristics is essential for implementation of assisted reproduction programs, as well as reproductive management in the species.
Collapse
Affiliation(s)
- Bruna Silvatti
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil.
| | | | - Pedro Nacib Jorge-Neto
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | | | | | | | | | - Roberta Ferreira Leite
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - João Diego de Agostini Losano
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Giulia Kiyomi Vechiato Kawai
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Marcilio Nichi
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Cristiane Schilbach Pizzutto
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| |
Collapse
|
22
|
Spitzer R, Norman AJ, Königsson H, Schiffthaler B, Spong G. De novo discovery of SNPs for genotyping endangered sun parakeets (Aratinga solstitialis) in Guyana. CONSERV GENET RESOUR 2020. [DOI: 10.1007/s12686-020-01151-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Abstract
Parrots (Psittaciformes) are among the most endangered groups of birds today and remain threatened by habitat loss and exploitation for the live bird trade. Under such conditions, reliable and non-invasive monitoring techniques are crucial for successful conservation measures. In this study, we developed a panel of 86 high quality SNPs for genotyping endangered sun parakeets (Aratinga solstitialis) in Guyana, which form one of the last known breeding populations of this South American species in the wild. Genotyping was tested on different types of samples (blood, feathers, feces, beak and cloacal swabs). While blood performed best, feathers and feces also yielded reliable results and could thus be used as non-invasive sources of DNA for future population monitoring. Discriminant Analysis of Principal Components (DAPC) on genotypes revealed that Guyanese sun parakeets clustered separately from other psittacine species as well as conspecifics from a captive population. A priori known first-order kinships were also adequately detected by the SNP panel. Using a series of experimental contaminations, we found that contamination from other psittacine species and slight contamination (~ 10%) from conspecifics did not prevent successful genotyping and recognition of individuals. We show that instances of higher conspecific contamination (~ 50%) can be detected through an increased level of heterozygosity that falls outside the distribution of uncontaminated samples.
Collapse
|
23
|
Vernasco BJ, Moore IT. Testosterone as a mediator of the tradeoff between cooperation and competition in the context of cooperative reproductive behaviors. Gen Comp Endocrinol 2020; 288:113369. [PMID: 31857075 DOI: 10.1016/j.ygcen.2019.113369] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 11/18/2019] [Accepted: 12/13/2019] [Indexed: 11/20/2022]
Abstract
Behavioral tradeoffs occur when the expression of one behavior detracts from the expression of another. Understanding the proximate mediators of behavioral tradeoffs is important as these tradeoffs can act as potential constraints on evolutionary responses to selection. Here, we describe the tradeoff between cooperation and competition faced by species that exhibit cooperative reproductive behaviors and propose that testosterone is a key hormonal mediator of the tradeoff. Cooperative reproductive behaviors occur when multiple individuals coordinate their efforts to gain a reproductive advantage over other individuals and/or those individuals attempting to reproduce in absence of cooperation. We propose that testosterone, a sex steroid known to mediate a number of physiological and behavioral actions associated with reproductive competition, is involved in mediating the tradeoff between cooperation and competition. To support this proposition, we first describe the importance of individual variation in behavior to the evolution of cooperative behaviors. We then describe how proximate mechanisms represent a prominent source of individual variation in social behaviors and highlight evidence suggesting testosterone mediates variation in cooperative behaviors. Two case studies in which the relationship between testosterone and cooperative behaviors have been investigated in detail are then summarized. Throughout we highlight the importance of studying individual variation to understand the mechanistic basis of behaviors, behavioral tradeoffs, and the evolution of cooperative reproductive behaviors more broadly.
Collapse
Affiliation(s)
- Ben J Vernasco
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA; School of Biological Sciences, Washington State University, Pullman, WA, USA.
| | - Ignacio T Moore
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| |
Collapse
|
24
|
Thorley J, Duncan C, Sharp SP, Gaynor D, Manser MB, Clutton-Brock T. Sex-independent senescence in a cooperatively breeding mammal. J Anim Ecol 2020; 89:1080-1093. [PMID: 31943191 DOI: 10.1111/1365-2656.13173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/28/2019] [Indexed: 11/30/2022]
Abstract
Researchers studying mammals have frequently interpreted earlier or faster rates of ageing in males as resulting from polygyny and the associated higher costs of reproductive competition. Yet, few studies conducted on wild populations have compared sex-specific senescence trajectories outside of polygynous species, making it difficult to make generalized inferences on the role of reproductive competition in driving senescence, particularly when other differences between males and females might also contribute to sex-specific changes in performance across lifespan. Here, we examine age-related variation in body mass, reproductive output and survival in dominant male and female meerkats, Suricata suricatta. Meerkats are socially monogamous cooperative breeders where a single dominant pair virtually monopolizes reproduction in each group and subordinate group members help to rear offspring produced by breeders. In contrast to many polygynous societies, we find that neither the onset nor the rate of senescence in body mass or reproductive output shows clear differences between males and females. Both sexes also display similar patterns of age-related survival across lifespan, but unlike most wild vertebrates, survival senescence (increases in annual mortality with rising age) was absent in dominants of both sexes, and as a result, the fitness costs of senescence were entirely attributable to declines in reproductive output from mid- to late-life. We suggest that the potential for intrasexual competition to increase rates of senescence in females-who are hormonally masculinized and frequently aggressive-is offset by their ability to maintain longer tenures of dominance than males, and that these processes when combined lead to similar patterns of senescence in both sexes. Our results stress the need to consider the form and intensity of sexual competition as well as other sex-specific features of life history when investigating the operation of senescence in wild populations.
Collapse
Affiliation(s)
- Jack Thorley
- Department of Zoology, University of Cambridge, Cambridge, UK.,Kalahari Research Centre, Kuruman River Reserve, South Africa
| | - Christopher Duncan
- Department of Zoology, University of Cambridge, Cambridge, UK.,Kalahari Research Centre, Kuruman River Reserve, South Africa
| | - Stuart P Sharp
- Lancaster Environment Centre, Lancaster University, Lancashire, UK
| | - David Gaynor
- Kalahari Research Centre, Kuruman River Reserve, South Africa.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Marta B Manser
- Kalahari Research Centre, Kuruman River Reserve, South Africa.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa.,Animal Behaviour, Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, UK.,Kalahari Research Centre, Kuruman River Reserve, South Africa.,Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
25
|
Mutwill AM, Zimmermann TD, Reuland C, Fuchs S, Kunert J, Richter SH, Kaiser S, Sachser N. High Reproductive Success Despite Queuing - Socio-Sexual Development of Males in a Complex Social Environment. Front Psychol 2019; 10:2810. [PMID: 31920852 PMCID: PMC6928119 DOI: 10.3389/fpsyg.2019.02810] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 11/28/2019] [Indexed: 11/13/2022] Open
Abstract
The start of actual breeding in male social mammals can occur long after individuals attain sexual maturity. Mainly prevented from reproduction by older and dominant males, young males often queue until strong enough to compete for favorable social positions and, in this way, to obtain access to females. However, to what extent maturing males also apply tactics to reproduce before this time is largely unknown. Therefore, the aim of the present study was to elucidate male socio-sexual development from onset of sexual maturity through first mating success until the achievement of a stable social position in a complex social environment. For this purpose, guinea pigs were used as a model system and reproductive success of males living in large mixed-sex colonies was assessed during their first year of life. As a reference, males in a mixed-sex pair situation were examined. Pair-housed males reproduced for the first time around the onset of sexual maturity whereas colony-housed males did so much later in life and with a considerably higher variance. In colonies, reproductive success was significantly affected by dominance status. Dominance itself was age-dependent, with older males having significantly higher dominance ranks than younger males. Surprisingly, both younger and older colony-housed males attained substantial reproductive success of comparable amounts. Thus, younger males reproduced irrespective of queuing and already before reaching a high social status. This mating success of maturing males was most likely achieved via several reproductive tactics which were flexibly applied with the onset of sexual maturity. The period of socio-sexual development before a stable social position is established may, therefore, be a time during which male mammals use flexible behavioral tactics to achieve reproductive success more frequently than commonly is presumed. In addition, the findings strongly indicate that high behavioral plasticity exists well beyond sexual maturity.
Collapse
Affiliation(s)
- Alexandra M Mutwill
- Department of Behavioural Biology, University of Münster, Münster, Germany.,Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | | | - Charel Reuland
- Department of Behavioural Biology, University of Münster, Münster, Germany
| | - Sebastian Fuchs
- Faculty of Statistics, Technical University of Dortmund, Dortmund, Germany
| | - Joachim Kunert
- Faculty of Statistics, Technical University of Dortmund, Dortmund, Germany
| | - S Helene Richter
- Department of Behavioural Biology, University of Münster, Münster, Germany.,Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - Sylvia Kaiser
- Department of Behavioural Biology, University of Münster, Münster, Germany.,Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - Norbert Sachser
- Department of Behavioural Biology, University of Münster, Münster, Germany.,Münster Graduate School of Evolution, University of Münster, Münster, Germany
| |
Collapse
|
26
|
Cram DL, Jungwirth A, Spence-Jones H, Clutton-Brock T. Reproductive conflict resolution in cooperative breeders. Behav Ecol 2019. [DOI: 10.1093/beheco/arz143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Female infanticide is common in animal societies where groups comprise multiple co-breeding females. To reduce the risk that their offspring are killed, mothers can synchronize breeding and pool offspring, making it hard for females to avoid killing their own young. However, female reproductive conflict does not invariably result in reproductive synchrony, and we lack a general hypothesis explaining the variation in conflict resolution strategies seen across species. Here, we investigate the fitness consequences of birth timing relative to other females and the prevalence of birth synchrony in cooperatively breeding Kalahari meerkats (Suricata suricatta). We show that, although there would be substantial benefits to females in synchronizing births and reducing their risk of infanticide, birth synchrony is rare. Since precise breeding synchrony has evolved in a related species with similar infanticidal female reproductive conflict, its absence in meerkats requires an evolutionary explanation. We therefore explore the costs and benefits of synchronizing breeding in two theoretical models, each of which contrasts synchrony with an alternative reproductive strategy: (i) breeding opportunistically and accepting fitness losses to infanticide or (ii) suppressing the reproduction of others to prevent infanticide. Our models show that the costs of synchrony constrain its development if subordinates breed infrequently, and that selection instead favors the suppression of subordinate reproduction by the dominant and opportunistic reproduction by subordinates. Together, our results suggest that the resolution of reproductive conflict in animal societies is shaped by differential breeding propensities among female group members, leading to divergent conflict resolution strategies even in closely related species.
Collapse
Affiliation(s)
- Dominic L Cram
- Department of Zoology, University of Cambridge, Cambridge, UK
- Kalahari Meerkat Project, Kalahari Research Centre, Van Zylsrus, Northern Cape, South Africa
| | - Arne Jungwirth
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Helen Spence-Jones
- Kalahari Meerkat Project, Kalahari Research Centre, Van Zylsrus, Northern Cape, South Africa
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, UK
- Kalahari Meerkat Project, Kalahari Research Centre, Van Zylsrus, Northern Cape, South Africa
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
27
|
Wright E, Galbany J, McFarlin SC, Ndayishimiye E, Stoinski TS, Robbins MM. Male body size, dominance rank and strategic use of aggression in a group-living mammal. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.03.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
28
|
Duncan C, Gaynor D, Clutton-Brock T, Dyble M. The Evolution of Indiscriminate Altruism in a Cooperatively Breeding Mammal. Am Nat 2019; 193:841-851. [PMID: 31094597 DOI: 10.1086/703113] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Kin selection theory suggests that altruistic behaviors can increase the fitness of altruists when recipients are genetic relatives. Although selection can favor the ability of organisms to preferentially cooperate with close kin, indiscriminately helping all group mates may yield comparable fitness returns if relatedness within groups is very high. Here, we show that meerkats (Suricata suricatta) are largely indiscriminate altruists who do not alter the amount of help provided to pups or group mates in response to their relatedness to them. We present a model showing that indiscriminate altruism may yield greater fitness payoffs than kin discrimination where most group members are close relatives and errors occur in the estimation of relatedness. The presence of errors in the estimation of relatedness provides a feasible explanation for associations between kin discriminative helping and group relatedness in eusocial and cooperatively breeding animals.
Collapse
|
29
|
Dubuc C, Clutton‐Brock TH. Male immigration triggers increased growth in subordinate female meerkats. Ecol Evol 2019; 9:1127-1134. [PMID: 30805146 PMCID: PMC6374659 DOI: 10.1002/ece3.4801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 11/04/2018] [Accepted: 11/12/2018] [Indexed: 11/30/2022] Open
Abstract
There is increasing evidence that some vertebrates can adjust their growth rate in relation to changes in the social context that affect their probability of breeding. Here, we show that, in meerkats (Suricata suricatta), which are singular cooperative breeders, subordinate females increase in body mass after their father is replaced as the dominant male in their natal group by an immigrant male, giving them regular access to an unfamiliar and unrelated mating partner, while their brothers showed no similar increase nor did subordinate females living in other stable groups (where male immigration did not occur did) in this time period. Moreover, subordinate females showed a greater increase in growth rate when their father was succeeded by an unfamiliar immigrant male than when he was replaced by a familiar male who was already resident. These results suggest that female meerkats can adjust their rate of growth to changes in the kinship composition of their groups that provide them with increased access to unrelated breeding partners, which may occur in other mammals as well when breeding opportunities change.
Collapse
Affiliation(s)
| | - Tim H. Clutton‐Brock
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Department of Zoology and Entomology, Mammal Research InstituteUniversity of PretoriaPretoriaSouth Africa
| |
Collapse
|
30
|
Duncan C, Gaynor D, Clutton-Brock T. The importance of being beta: female succession in a cooperative breeder. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.10.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
31
|
Cram DL, Monaghan P, Gillespie R, Dantzer B, Duncan C, Spence-Jones H, Clutton-Brock T. Rank-Related Contrasts in Longevity Arise from Extra-Group Excursions Not Delayed Senescence in a Cooperative Mammal. Curr Biol 2018; 28:2934-2939.e4. [DOI: 10.1016/j.cub.2018.07.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 05/14/2018] [Accepted: 07/08/2018] [Indexed: 12/11/2022]
|
32
|
Smyth KN, Caruso NM, Davies CS, Clutton-Brock TH, Drea CM. Social and endocrine correlates of immune function in meerkats: implications for the immunocompetence handicap hypothesis. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180435. [PMID: 30225031 PMCID: PMC6124081 DOI: 10.1098/rsos.180435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
Social status can mediate effects on the immune system, with profound consequences for individual health; nevertheless, most investigators of status-related disparities in free-ranging animals have used faecal parasite burdens to proxy immune function in the males of male-dominant species. We instead use direct measures of innate immune function (complement and natural antibodies) to examine status-related immunocompetence in both sexes of a female-dominant species. The meerkat is a unique model for such a study because it is a cooperatively breeding species in which status-related differences are extreme, evident in reproductive skew, morphology, behaviour, communication and physiology, including that dominant females naturally express the greatest total androgen (androstenedione plus testosterone) concentrations. We found that, relative to subordinates, dominant animals had reduced serum bacteria-killing abilities; also, relative to subordinate females, dominant females had reduced haemolytic complement activities. Irrespective of an individual's sex or social status, androstenedione concentrations (but not body condition, age or reproductive activity) negatively predicted concurrent immunocompetence. Thus, dominant meerkats of both sexes are immunocompromised. Moreover, in female meerkats, androstenedione perhaps acting directly or via local conversion, may exert a double-edged effect of promoting dominance and reproductive success at the cost of increased parasitism and reduced immune function. Given the prominent signalling of dominance in female meerkats, these findings may relate to the immunocompetence handicap hypothesis (ICHH); however, our data would suggest that the endocrine mechanism underlying the ICHH need not be mediated solely by testosterone and might explain trade-offs in females, as well as in males.
Collapse
Affiliation(s)
- Kendra N. Smyth
- University Program in Ecology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| | - Nicholas M. Caruso
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, USA
| | - Charli S. Davies
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| | - Tim H. Clutton-Brock
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
- Department of Zoology, University of Cambridge, Cambridge, UK
- Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Christine M. Drea
- University Program in Ecology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Department of Biology, Duke University, Durham, NC, USA
- Kalahari Research Trust, Kuruman River Reserve, Van Zylsrus, Northern Cape, South Africa
| |
Collapse
|
33
|
Bateman AW, Ozgul A, Krkošek M, Clutton-Brock TH. Matrix Models of Hierarchical Demography: Linking Group- and Population-Level Dynamics in Cooperative Breeders. Am Nat 2018; 192:188-203. [DOI: 10.1086/698217] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
34
|
Spatial structure of foraging meerkat groups is affected by both social and ecological factors. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2490-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
35
|
Nelson-Flower MJ, Flower TP, Ridley AR. Sex differences in the drivers of reproductive skew in a cooperative breeder. Mol Ecol 2018; 27:2435-2446. [PMID: 29663552 DOI: 10.1111/mec.14587] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/25/2018] [Accepted: 03/26/2018] [Indexed: 01/08/2023]
Abstract
Many cooperatively breeding societies are characterized by high reproductive skew, such that some socially dominant individuals breed, while socially subordinate individuals provide help. Inbreeding avoidance serves as a source of reproductive skew in many high-skew societies, but few empirical studies have examined sources of skew operating alongside inbreeding avoidance or compared individual attempts to reproduce (reproductive competition) with individual reproductive success. Here, we use long-term genetic and observational data to examine factors affecting reproductive skew in the high-skew cooperatively breeding southern pied babbler (Turdoides bicolor). When subordinates can breed, skew remains high, suggesting factors additional to inbreeding avoidance drive skew. Subordinate females are more likely to compete to breed when older or when ecological constraints on dispersal are high, but heavy subordinate females are more likely to successfully breed. Subordinate males are more likely to compete when they are older, during high ecological constraints, or when they are related to the dominant male, but only the presence of within-group unrelated subordinate females predicts subordinate male breeding success. Reproductive skew is not driven by reproductive effort, but by forces such as intrinsic physical limitations and intrasexual conflict (for females) or female mate choice, male mate-guarding and potentially reproductive restraint (for males). Ecological conditions or "outside options" affect the occurrence of reproductive conflict, supporting predictions of recent synthetic skew models. Inbreeding avoidance together with competition for access to reproduction may generate high skew in animal societies, and disparate processes may be operating to maintain male vs. female reproductive skew in the same species.
Collapse
Affiliation(s)
- Martha J Nelson-Flower
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Tom P Flower
- Department of Biology, Capilano University, North Vancouver, BC, Canada.,Percy FitzPatrick Institute of African Ornithology, DST NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - Amanda R Ridley
- Percy FitzPatrick Institute of African Ornithology, DST NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa.,Centre for Evolutionary Biology, University of Western Australia, Crawley, WA, Australia
| |
Collapse
|
36
|
Stress levels of dominants reflect underlying conflicts with subordinates in a cooperatively breeding species. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2484-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
37
|
Borrego N, Ozgul A, Slotow R, Packer C. Lion population dynamics: do nomadic males matter? Behav Ecol 2018. [DOI: 10.1093/beheco/ary018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Natalia Borrego
- School of Life Sciences, University of KwaZulu-Natal, University Rd, Westville, South Africa
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Falcon Heights, St. Paul, MN, USA
| | - Arpat Ozgul
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurestrasse, Zurich, Switzerland
| | - Rob Slotow
- School of Life Sciences, University of KwaZulu-Natal, University Rd, Westville, South Africa
| | - Craig Packer
- Department of Ecology, Evolution, and Behavior, University of Minnesota, Falcon Heights, St. Paul, MN, USA
| |
Collapse
|
38
|
Cram DL, Monaghan P, Gillespie R, Clutton-Brock T. Effects of early-life competition and maternal nutrition on telomere lengths in wild meerkats. Proc Biol Sci 2018; 284:rspb.2017.1383. [PMID: 28855370 DOI: 10.1098/rspb.2017.1383] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/21/2017] [Indexed: 12/21/2022] Open
Abstract
Early-life adversity can affect health, survival and fitness later in life, and recent evidence suggests that telomere attrition may link early conditions with their delayed consequences. Here, we investigate the link between early-life competition and telomere length in wild meerkats. Our results show that, when multiple females breed concurrently, increases in the number of pups in the group are associated with shorter telomeres in pups. Given that pups from different litters compete for access to milk, we tested whether this effect is due to nutritional constraints on maternal milk production, by experimentally supplementing females' diets during gestation and lactation. While control pups facing high competition had shorter telomeres, the negative effects of pup number on telomere lengths were absent when maternal nutrition was experimentally improved. Shortened pup telomeres were associated with reduced survival to adulthood, suggesting that early-life competition for nutrition has detrimental fitness consequences that are reflected in telomere lengths. Dominant females commonly kill pups born to subordinates, thereby reducing competition and increasing growth rates of their own pups. Our work suggests that an additional benefit of infanticide may be that it also reduces telomere shortening caused by competition for resources, with associated benefits for offspring ageing profiles and longevity.
Collapse
Affiliation(s)
- Dominic L Cram
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK .,Kalahari Meerkat Project, Kuruman River Reserve, PO Box 64, Van Zylsrus, Northern Cape 8467, South Africa
| | - Pat Monaghan
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Robert Gillespie
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Kalahari Meerkat Project, Kuruman River Reserve, PO Box 64, Van Zylsrus, Northern Cape 8467, South Africa
| |
Collapse
|
39
|
Dantzer B, Goncalves IB, Spence-Jones HC, Bennett NC, Heistermann M, Ganswindt A, Dubuc C, Gaynor D, Manser MB, Clutton-Brock TH. The influence of stress hormones and aggression on cooperative behaviour in subordinate meerkats. Proc Biol Sci 2018; 284:rspb.2017.1248. [PMID: 28931736 DOI: 10.1098/rspb.2017.1248] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 08/22/2017] [Indexed: 11/12/2022] Open
Abstract
In cooperative breeders, aggression from dominant breeders directed at subordinates may raise subordinate stress hormone (glucocorticoid) concentrations. This may benefit dominants by suppressing subordinate reproduction but it is uncertain whether aggression from dominants can elevate subordinate cooperative behaviour, or how resulting changes in subordinate glucocorticoid concentrations affect their cooperative behaviour. We show here that the effects of manipulating glucocorticoid concentrations in wild meerkats (Suricata suricatta) on cooperative behaviour varied between cooperative activities as well as between the sexes. Subordinates of both sexes treated with a glucocorticoid receptor antagonist (mifepristone) exhibited significantly more pup protection behaviour (babysitting) compared to those treated with glucocorticoids (cortisol) or controls. Females treated with mifepristone had a higher probability of exhibiting pup food provisioning (pup-feeding) compared to those treated with cortisol. In males, there were no treatment effects on the probability of pup-feeding, but those treated with cortisol gave a higher proportion of the food they found to pups than those treated with mifepristone. Using 19 years of behavioural data, we also show that dominant females did not increase the frequency with which they directed aggression at subordinates at times when the need for assistance was highest. Our results suggest that it is unlikely that dominant females manipulate the cooperative behaviour of subordinates through the effects of aggression on their glucocorticoid levels and that the function of aggression directed at subordinates is probably to reduce the probability they will breed.
Collapse
Affiliation(s)
- Ben Dantzer
- Department of Zoology, University of Cambridge, Cambridge, UK .,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa
| | - Ines Braga Goncalves
- Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Switzerland
| | | | - Nigel C Bennett
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Michael Heistermann
- Endocrinology Laboratory, German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany
| | - Andre Ganswindt
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.,Endocrine Research Laboratory, Department of Anatomy and Physiology, University of Pretoria, 0110 Onderstepoort, South Africa
| | - Constance Dubuc
- Department of Zoology, University of Cambridge, Cambridge, UK.,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa
| | - David Gaynor
- Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Marta B Manser
- Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Switzerland
| | - Tim H Clutton-Brock
- Department of Zoology, University of Cambridge, Cambridge, UK.,Kalahari Meerkat Project, Kuruman River Reserve, Northern Cape, South Africa.,Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
40
|
Dantzer B, Bennett NC, Clutton-Brock TH. Social conflict and costs of cooperation in meerkats are reflected in measures of stress hormones. Behav Ecol 2017. [DOI: 10.1093/beheco/arx077] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
41
|
Patterson S, Drewe JA, Pfeiffer DU, Clutton-Brock TH. Social and environmental factors affect tuberculosis related mortality in wild meerkats. J Anim Ecol 2017; 86:442-450. [PMID: 28186336 PMCID: PMC5413830 DOI: 10.1111/1365-2656.12649] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 01/31/2017] [Indexed: 11/27/2022]
Abstract
Tuberculosis (TB) is an important and widespread disease of wildlife, livestock and humans world‐wide, but long‐term empirical datasets describing this condition are rare. A population of meerkats (Suricata suricatta) in South Africa's Kalahari Desert have been diagnosed with Mycobacterium suricattae, a novel strain of TB, causing fatal disease in this group‐living species. This study aimed to find characteristics associated with clinical TB in meerkats. These characteristics could subsequently be used to identify ‘at‐risk’ animals within a population, and target these individuals for control measures. We conducted a retrospective study based on a unique, long‐term life‐history dataset of over 2000 individually identified animals covering a 14‐year period after the first confirmatory diagnosis of TB in this population in 2001. Individual‐ and group‐level risk factors were analysed using time‐dependent Cox regression to examine their potential influence on the time to development of end‐stage TB. Cases of disease involved 144 individuals in 27 of 73 social groups, across 12 of 14 years (an incidence rate of 3·78 cases/100 study years). At the individual level, increasing age had the greatest effect on risk of disease with a hazard ratio of 4·70 (95% CI: 1·92–11·53, P < 0·01) for meerkats aged 24–48 months, and a hazard ratio of 9·36 (3·34–26·25, P < 0·001) for animals aged over 48 months (both age categories compared with animals aged below 24 months). Previous group history of TB increased the hazard by a factor of 4·29 (2·00–9·17, P < 0·01), and an interaction was found between this variable and age. At a group level, immigrations of new group members in the previous year increased hazard by a factor of 3·00 (1·23–7·34, P = 0·016). There was weaker evidence of an environmental effect with a hazard ratio for a low rainfall (<200 mm) year of 2·28 (0·91–5·72, P = 0·079). Our findings identify potential individual characteristics on which to base targeted control measures such as vaccination. Additional data on the dynamics of the infection status of individuals and how this changes over time would complement these findings by enhancing understanding of disease progression and transmission, and thus the implications of potential management measures.
Collapse
Affiliation(s)
- Stuart Patterson
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| | - Julian A Drewe
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| | - Dirk U Pfeiffer
- Veterinary Epidemiology, Economics and Public Health Group, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK.,School of Veterinary Medicine, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR
| | - Tim H Clutton-Brock
- Large Animal Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.,Mammal Research Institute, University of Pretoria, Hatfield, Pretoria, South Africa
| |
Collapse
|
42
|
|
43
|
Braga Goncalves I, Heistermann M, Santema P, Dantzer B, Mausbach J, Ganswindt A, Manser MB. Validation of a Fecal Glucocorticoid Assay to Assess Adrenocortical Activity in Meerkats Using Physiological and Biological Stimuli. PLoS One 2016; 11:e0153161. [PMID: 27077741 PMCID: PMC4831846 DOI: 10.1371/journal.pone.0153161] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/24/2016] [Indexed: 12/03/2022] Open
Abstract
In mammals, glucocorticoid (i.e. GC) levels have been associated with specific life-history stages and transitions, reproductive strategies, and a plethora of behaviors. Assessment of adrenocortical activity via measurement of glucocorticoid metabolites in feces (FGCM) has greatly facilitated data collection from wild animals, due to its non-invasive nature, and thus has become an established tool in behavioral ecology and conservation biology. The aim of our study was to validate a fecal glucocorticoid assay for assessing adrenocortical activity in meerkats (Suricata suricatta), by comparing the suitability of three GC enzyme immunoassays (corticosterone, 11β-hydroxyetiocholanolone and 11oxo-etiocholanolone) in detecting FGCM increases in adult males and females following a pharmacological challenge with adrenocorticotropic hormone (ACTH) and biological stimuli. In addition, we investigated the time course characterizing FGCM excretion, the effect of age, sex and time of day on FGCM levels and assessed the potential effects of soil contamination (sand) on FGCM patterns. Our results show that the group specific 11β-hydroxyetiocholanolone assay was most sensitive to FGCM alterations, detecting significant and most distinctive elevations in FGCM levels around 25 h after ACTH administration. We found no age and sex differences in basal FGCM or on peak response levels to ACTH, but a marked diurnal pattern, with FGCM levels being substantially higher in the morning than later during the day. Soil contamination did not significantly affect FGCM patterns. Our results emphasize the importance of conducting assay validations to characterize species-specific endocrine excretion patterns, a crucial step to all animal endocrinology studies using a non-invasive approach.
Collapse
Affiliation(s)
- Ines Braga Goncalves
- Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Michael Heistermann
- Endocrinology Laboratory, German Primate Center, Kellnerweg 4, D-37077, Göttingen, Germany
| | - Peter Santema
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom
| | - Ben Dantzer
- Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom
| | - Jelena Mausbach
- Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Andre Ganswindt
- Endocrine Research Laboratory, Department of Anatomy and Physiology, University of Pretoria, 0110, Onderstepoort, South Africa
| | - Marta B. Manser
- Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| |
Collapse
|
44
|
delBarco-Trillo J, Greene LK, Goncalves IB, Fenkes M, Wisse JH, Drewe JA, Manser MB, Clutton-Brock T, Drea CM. Beyond aggression: Androgen-receptor blockade modulates social interaction in wild meerkats. Horm Behav 2016; 78:95-106. [PMID: 26545817 DOI: 10.1016/j.yhbeh.2015.11.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 11/01/2015] [Accepted: 11/02/2015] [Indexed: 01/26/2023]
Abstract
In male vertebrates, androgens are inextricably linked to reproduction, social dominance, and aggression, often at the cost of paternal investment or prosociality. Testosterone is invoked to explain rank-related reproductive differences, but its role within a status class, particularly among subordinates, is underappreciated. Recent evidence, especially for monogamous and cooperatively breeding species, suggests broader androgenic mediation of adult social interaction. We explored the actions of androgens in subordinate, male members of a cooperatively breeding species, the meerkat (Suricata suricatta). Although male meerkats show no rank-related testosterone differences, subordinate helpers rarely reproduce. We blocked androgen receptors, in the field, by treating subordinate males with the antiandrogen, flutamide. We monitored androgen concentrations (via baseline serum and time-sequential fecal sampling) and recorded behavior within their groups (via focal observation). Relative to controls, flutamide-treated animals initiated less and received more high-intensity aggression (biting, threatening, feeding competition), engaged in more prosocial behavior (social sniffing, grooming, huddling), and less frequently initiated play or assumed a 'dominant' role during play, revealing significant androgenic effects across a broad range of social behavior. By contrast, guarding or vigilance and measures of olfactory and vocal communication in subordinate males appeared unaffected by flutamide treatment. Thus, androgens in male meerkat helpers are aligned with the traditional trade-off between promoting reproductive and aggressive behavior at a cost to affiliation. Our findings, based on rare endocrine manipulation in wild mammals, show a more pervasive role for androgens in adult social behavior than is often recognized, with possible relevance for understanding tradeoffs in cooperative systems.
Collapse
Affiliation(s)
- Javier delBarco-Trillo
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Department of Evolutionary Anthropology, Duke University, Durham, USA; School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK
| | - Lydia K Greene
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Department of Evolutionary Anthropology, Duke University, Durham, USA; University Program in Ecology, Duke University, Durham, USA
| | - Ines Braga Goncalves
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Miriam Fenkes
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Jillian H Wisse
- Department of Evolutionary Anthropology, Duke University, Durham, USA
| | - Julian A Drewe
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Royal Veterinary College, University of London, London, UK
| | - Marta B Manser
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland; Mammal Research Institute, University of Pretoria, Pretoria, South Africa
| | - Tim Clutton-Brock
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Mammal Research Institute, University of Pretoria, Pretoria, South Africa; Department of Zoology, University of Cambridge, Cambridge, UK
| | - Christine M Drea
- Kalahari Research Trust, Kuruman River Reserve, Northern Cape, South Africa; Department of Evolutionary Anthropology, Duke University, Durham, USA; University Program in Ecology, Duke University, Durham, USA; Department of Biology, Duke University, Durham, USA.
| |
Collapse
|
45
|
Georgiev A, Christie D, Rosenfield K, Ruiz-Lambides A, Maldonado E, Emery Thompson M, Maestripieri D. Breaking the succession rule: the costs and benefits of an alpha-status take-over by an immigrant rhesus macaque on Cayo Santiago. BEHAVIOUR 2016. [DOI: 10.1163/1568539x-00003344] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Explaining intraspecific variation in reproductive tactics hinges on measuring associated costs and benefits. Yet, this is difficult if alternative (purportedly less optimal) tactics remain unobserved. We describe a rare alpha-position take-over by an immigrant male rhesus macaque in a population where males typically gain rank via succession. Unusually, male aggressiveness after the take-over correlated with rank and mating success. The new alpha achieved the highest mating and reproductive success. Nevertheless, he sired only 4 infants due to high extra-group paternity (59.3%). The costs of his immigration tactic were high: after the mating season ended, unable to deter coalitionary attacks by resident males, he was overthrown. The following year he had the highest relative annual weight loss and levels of immune activation among males in the group. Succession-based rank-acquisition in large, provisioned groups of macaques thus appears to be actively maintained by resident males, who impose high costs on challengers.
Collapse
Affiliation(s)
- Alexander V. Georgiev
- Institute for Mind and Biology, The University of Chicago, 940 E57th Street, Chicago, IL 60637, USA
- Department of Anthropology, Northwestern University, 1810 Hinman Avenue, Evanston, IL 60208, USA
| | - Diana Christie
- Department of Anthropology, University of Oregon, 1321 Kincaid Street, Eugene, OR 97403, USA
| | - Kevin A. Rosenfield
- Department of Life Sciences, University of Roehampton, Holybourne Avenue, London SW15 4JD, UK
| | - Angelina V. Ruiz-Lambides
- Caribbean Primate Research Center–Cayo Santiago, University of Puerto Rico, Punta Santiago, PR 00741, Puerto Rico
| | - Elizabeth Maldonado
- Caribbean Primate Research Center–Cayo Santiago, University of Puerto Rico, Punta Santiago, PR 00741, Puerto Rico
| | - Melissa Emery Thompson
- Department of Anthropology, University of New Mexico, 500 University Boulevard NE, Albuquerque, NM 87131, USA
| | - Dario Maestripieri
- Institute for Mind and Biology, The University of Chicago, 940 E57th Street, Chicago, IL 60637, USA
| |
Collapse
|
46
|
Male-male competition is not costly to dominant males in a cooperatively breeding bird. Behav Ecol Sociobiol 2015. [DOI: 10.1007/s00265-015-2011-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
47
|
Norman AJ, Spong G. Single nucleotide polymorphism-based dispersal estimates using noninvasive sampling. Ecol Evol 2015; 5:3056-65. [PMID: 26357536 PMCID: PMC4559049 DOI: 10.1002/ece3.1588] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 06/04/2015] [Accepted: 06/05/2015] [Indexed: 02/06/2023] Open
Abstract
Quantifying dispersal within wild populations is an important but challenging task. Here we present a method to estimate contemporary, individual-based dispersal distance from noninvasively collected samples using a specialized panel of 96 SNPs (single nucleotide polymorphisms). One main issue in conducting dispersal studies is the requirement for a high sampling resolution at a geographic scale appropriate for capturing the majority of dispersal events. In this study, fecal samples of brown bear (Ursus arctos) were collected by volunteer citizens, resulting in a high sampling resolution spanning over 45,000 km2 in Gävleborg and Dalarna counties in Sweden. SNP genotypes were obtained for unique individuals sampled (n = 433) and subsequently used to reconstruct pedigrees. A Mantel test for isolation by distance suggests that the sampling scale was appropriate for females but not for males, which are known to disperse long distances. Euclidean distance was estimated between mother and offspring pairs identified through the reconstructed pedigrees. The mean dispersal distance was 12.9 km (SE 3.2) and 33.8 km (SE 6.8) for females and males, respectively. These results were significantly different (Wilcoxon’s rank-sum test: P-value = 0.02) and are in agreement with the previously identified pattern of male-biased dispersal. Our results illustrate the potential of using a combination of noninvasively collected samples at high resolution and specialized SNPs for pedigree-based dispersal models.
Collapse
Affiliation(s)
- Anita J Norman
- Molecular Ecology Group, Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences SE-901 83, Umeå, Sweden
| | - Göran Spong
- Molecular Ecology Group, Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences SE-901 83, Umeå, Sweden
| |
Collapse
|
48
|
|
49
|
Groenendijk J, Hajek F, Johnson PJ, Macdonald DW, Calvimontes J, Staib E, Schenck C. Demography of the giant otter (Pteronura brasiliensis) in Manu National Park, south-eastern Peru: implications for conservation. PLoS One 2014; 9:e106202. [PMID: 25162684 PMCID: PMC4146611 DOI: 10.1371/journal.pone.0106202] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/28/2014] [Indexed: 12/02/2022] Open
Abstract
The giant otter (Pteronura brasiliensis) is an endangered semi-aquatic carnivore of South America. We present findings on the demography of a population inhabiting the floodplain of Manu National Park, south-eastern Peru, arising from 14 annual dry season censuses over a 16 year period. The breeding system of territorial groups, including only a single breeding female with non-reproductive adult ‘helpers’, resulted in a low intrinsic rate of increase (0.03) and a slow recovery from decades of hunting for the pelt trade. This is explained by a combination of factors: (1) physiological traits such as late age at first reproduction and long generation time, (2) a high degree of reproductive skew, (3) small litters produced only once a year, and (4) a 50% mortality between den emergence and age of dispersal, as well as high mortality amongst dispersers (especially males). Female and male giant otters show similar traits with respect to average reproductive life-spans (female 5.4 yrs., male 5.2 yrs.) and average cub productivity (female 6.9, male 6.7 cubs per lifetime); the longest reproductive life spans were 11 and 13 years respectively. Individual reproductive success varied substantially and depended mainly on the duration of dominance tenure in the territory. When breeding females died, the reproductive position in the group was usually occupied by sisters or daughters (n = 11), with immigrant male partners. Male philopatry was not observed. The vulnerability of the Manu giant otter population to anthropogenic disturbance emphasises the importance of effective protection of core lake habitats in particular. Riverine forests are the most endangered ecosystem in the Department of Madre de Dios due to the concentration of gold mining, logging and agricultural activities in floodplains, highlighting the need for a giant otter habitat conservation corridor along the Madre de Dios River.
Collapse
Affiliation(s)
- Jessica Groenendijk
- San Diego Zoo Global Peru, Department of Cusco, Cusco, Perú
- Wildlife Conservation Research Unit, University of Oxford, Abingdon, Oxfordshire, United Kingdom
- Frankfurt Zoological Society, Frankfurt, Germany
- * E-mail:
| | - Frank Hajek
- Nature Services Peru, Department of Cusco, Cusco, Perú
- Frankfurt Zoological Society, Frankfurt, Germany
| | - Paul J. Johnson
- Wildlife Conservation Research Unit, University of Oxford, Abingdon, Oxfordshire, United Kingdom
| | - David W. Macdonald
- Wildlife Conservation Research Unit, University of Oxford, Abingdon, Oxfordshire, United Kingdom
| | - Jorge Calvimontes
- Environmental Studies and Research Center, University of Campinas, São Paulo, Brazil
- Frankfurt Zoological Society, Frankfurt, Germany
| | - Elke Staib
- Frankfurt Zoological Society, Frankfurt, Germany
| | | |
Collapse
|
50
|
Huchard E, Charmantier A, English S, Bateman A, Nielsen JF, Clutton-Brock T. Additive genetic variance and developmental plasticity in growth trajectories in a wild cooperative mammal. J Evol Biol 2014; 27:1893-904. [DOI: 10.1111/jeb.12440] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 05/23/2014] [Accepted: 05/26/2014] [Indexed: 11/27/2022]
Affiliation(s)
- E. Huchard
- LARG; Department of Zoology; University of Cambridge; Cambridge UK
| | - A. Charmantier
- LARG; Department of Zoology; University of Cambridge; Cambridge UK
- CEFE-CNRS; Montpellier Cedex 5 France
| | - S. English
- Department of Zoology; The Edward Grey Institute; University of Oxford, Oxford UK
| | - A. Bateman
- LARG; Department of Zoology; University of Cambridge; Cambridge UK
| | - J. F. Nielsen
- Institute of Evolutionary Biology; School of Biological Sciences; University of Edinburgh; Edinburgh UK
- Institute of Zoology; Zoological Society of London; London UK
| | - T. Clutton-Brock
- LARG; Department of Zoology; University of Cambridge; Cambridge UK
| |
Collapse
|