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Ugo Ripamonti - One of the best experts on this subject based on the ideXlab platform.
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cementogenesis and osteogenesis in periodontal tissue regeneration by recombinant human transforming growth factor β3 a pilot study in Papio ursinus
Journal of Clinical Periodontology, 2017Co-Authors: Ugo Ripamonti, Roland M. Klar, Caroline Dickens, Therese Dixpeek, Ruqayya Parak, Raquel DuarteAbstract:Objectives To investigate cementogenesis and alveolar bone induction during in vivo periodontal tissue regeneration upon implantation of hTGF-β3 in furcation defects of Papio ursinus and to evaluate the feasibility of gene expression studies. Materials and Methods Class II furcation defects (day 0) were prepared in mandibular first and second molars of three P. ursinus and on day 30 implanted with and without 75μg hTGF-β3 in Matrigel®matrix. On day 0, 30 and 90, cementum and alveolar bone were harvested for gene expression analyses. Coral-derived bioreactors with and without 250μg hTGF-β3 were implanted in the rectus abdominis to monitor tissue induction. Results hTGF-β3 induced cementogenesis with TGF-β3, Cementum Protein-1 (Cemp1) and Osteocalcin (OC) up-regulation, and down-regulation of BMP-2 and OP-1. Matrigel®matrix specimens showed up-regulation of BMP-2, TGF-β3, and OC, with down-regulation of OP-1 and Cemp1. hTGF-β3 induced alveolar bone with down-regulation of OP-1, TGF-β3, OC, and Cemp1. hTGF-β3 bioreactors induced bone at the periphery only. BMP-3, BMP-4, TGF-β1 and TGF-β3 were up-regulated in the adjacent muscle with TGF-β2 downregulation. Conclusions Cementogenesis and osteogenesis by hTGF-β3 entail the expression and up-regulation of TGF-β3, OC with fine tuning and modulation of BMP-2 and OP-1. This article is protected by copyright. All rights reserved.
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Redundancy and molecular evolution: the rapid Induction of bone formation by the mammalian transforming growth factor-β3 isoform
Frontiers Media S.A., 2016Co-Authors: Ugo Ripamonti, Caroline Dickens, Raquel Duarte, Ruqayya Parak, Therese Dix-peek, Roland Manfred KlarAbstract:The soluble osteogenic molecular signals of the transforming growth factor-β (TGF-β) supergene family are the molecular bases of the induction of bone formation and postnatal bone tissue morphogenesis with translation into clinical contexts. The mammalian TGF-β3 isoform, a pleiotropic member of the family, controls a vast array of biological processes including the induction of bone formation. Recombinant hTGF-β3 induces substantial bone formation when implanted with either collagenous bone matrices or coral-derived macroporous bioreactors in the rectus abdominis muscle of the non-human primate Papio ursinus. In marked contrast, the three mammalian TGF-βs do not initiate the induction of bone formation in rodents and lagomorphs. The induction of bone by hTGF-β3/preloaded bioreactors is orchestrated by inducing fibrin-fibronectin rings that structurally organize tissue patterning and morphogenesis within the macroporous spaces. Induced advancing extracellular matrix rings provide the structural anchorage for hyper chromatic cells, interpreted as differentiating osteoblasts re-programmed by hTGF-β3 from invading myoblastic and/or pericytic differentiated cells. Runx2 and Osteocalcin expression are significantly up-regulated correlating to multiple invading cells differentiating into the osteoblastic phenotype. Bioreactors pre-loaded with recombinant human Noggin (hNoggin), a BMPs antagonist, show down-regulation of BMP-2 and other profiled osteogenic proteins’ genes resulting in minimal bone formation. Coral-derived macroporous constructs preloaded with binary applications of hTGF-β3 and hNoggin also show down-regulation of BMP-2 with the induction of limited bone formation. The induction of bone formation by hTGF-β3 is via the BMPs pathway and it is thus blocked by hNoggin. Our systematic studies in Papio ursinus with translational hTGF-β3 in large cranio-mandibulo-facial defects in humans are now requesting the re-evaluation of Bone: formation by autoinduction in primate models including humans
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biological aspects of periodontal tissue regeneration cementogenesis and the induction of sharpey s fibres
journal of the South African Dental Association, 2013Co-Authors: Ansuyah Magan, Ugo RipamontiAbstract:The realm of periodontal tissue regeneration has a plethora of unanswered questions and challenges due to the complexity of restoring mineralised and fibrous connective tissues ultimately to be covered by epithelium in a very specific spatial organisation. Wound healing of the periodontium follows a highly ordered sequence of events that guides cellular morphology, differentiation, migration and proliferation and comprises a series of cellular, extracellular and molecular reciprocal interactions. The prerequisite for regeneration of any structure is the trio of a soluble molecular signal, a scaffold and responding stem cells. Striated muscle represents an abundant source of easily accessible tissue that contains several perivascular, pericytic and myoblastic cell niches capable of differentiating and inducing selected tissue phenotypes and morphogenesis. Morcellated autogenous rectus abdominis muscle combined with 75µg of hTGF-β3 in Matrigel® matrix implanted into non-human primate class II and III furcation defects induced greater alveolar bone formation and cementogenesis when compared to furcation defects without the addition of morcellated autogenous bone. In situ hybridisation and immunohistochemistry during embryonic development and tooth morphogenesis have shown synchronous but spatially different bone morphogenetic proteins (BMPs) expression during tissue induction and morphogenesis. Preclinical studies in the non-human primate Papio ursinus have shown a seemingly specific cementogenic function of osteogenic protein-1 (OP-1, also known as BMP-7) when treating Class II furcation defects of Papio ursinus. In context, hOP-1 is preferentially cementogenic when implanted into non-human primate class II and III furcation defects whilst hBMP-2 is highly osteogenic but not cementogenic when in contact with dentine extracellular matrix. Importantly, naturally-derived highly purified BMPs/OPs, recombinant hOP-1 and hTGF-β3 when implanted into non-human primates Class II and III furcation defects induce cementogenesis with morphologically and functionally oriented periodontal ligament fibres coursing within a newly formed highly vascular periodontal ligament space with Sharpey's fibres generated within the newly secreted cementoid matrix. The grand challenge of molecular and therapeutic implications is the biological significance of apparent redundancy. The presence of several homologous but molecularly different isoforms all endowed with the striking capacity of inducing "bone formation by autoinduction" indicates that there is a structure/activity profile amongst soluble osteogenic molecular signals; this suggests a therapeutic significance in clinical contexts. The structure/activity profile finely tunes the vast pleiotropic activities of the soluble molecular signals in mineralised and non-mineralised tissues profoundly modulating epithelial/mesenchymal tissue interactions. Significant advances in regenerative tissue engineering may be expected if ongoing research is tailored to provide further mechanistic and morphological insights into the relevance of the apparent redundancy and the structure/activity profile of the recombinant human osteogenic proteins. The presence of the structure/activity profile together with the biological significance of apparent redundancy will necessitate re-shaping and re-engineering developing newly devised targeted therapeutics for periodontal tissue engineering.
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cementogenesis and the induction of periodontal tissue regeneration by the osteogenic proteins of the transforming growth factor β superfamily
Journal of Periodontal Research, 2009Co-Authors: Ugo Ripamonti, Jeanclaude Petit, June TeareAbstract:: The antiquity and severity of periodontal diseases are demonstrated by the hard evidence of alveolar bone loss in gnathic remains of the Pliocene/Pleistocene deposits of the Bloubank Valley at Sterkfontein, Swartkrans and Kromdrai in South Africa. Extant Homo has characterized and cloned a superfamily of proteins which include the bone morphogenetic proteins that regulate tooth morphogenesis at different stages of development as temporally and spatially connected events. The induction of cementogenesis, periodontal ligament and alveolar bone regeneration are regulated by the co-ordinated expression of bone morphogenetic proteins. Naturally derived and recombinant human bone morphogenetic proteins induce periodontal tissue regeneration in mammals. Morphological analyses on undecalcified sections cut at 3-6 mum on a series of mandibular molar Class II and III furcation defects induced in the non-human primate Papio ursinus show the induction of cementogenesis. Sharpey's fibers nucleate as a series of composite collagen bundles within the cementoid matrix in close relation to embedded cementocytes. Osteogenic protein-1 and bone morphogenetic protein-2 possess a structure-activity profile, as shown by the morphology of tissue regeneration, preferentially cementogenic and osteogenic, respectively. In Papio ursinus, transforming growth factor-beta(3) also induces cementogenesis, with Sharpey's fibers inserting into newly formed alveolar bone. Capillary sprouting and invasion determine the sequential insertion and alignment of individual collagenic bundles. The addition of responding stem cells prepared by finely mincing fragments of autogenous rectus abdominis muscle significantly enhances the induction of periodontal tissue regeneration when combined with transforming growth factor-beta(3) implanted in Class II and III furcation defects of Papio ursinus.
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bone induction by recombinant human osteogenic protein 1 hop 1 bmp 7 in the primate Papio ursinus with expression of mrna of gene products of the tgf β superfamily
Journal of Cellular and Molecular Medicine, 2005Co-Authors: Ugo RipamontiAbstract:: Predictable bone induction in clinical contexts requires information on the expression and cross regulation of gene products of the transforming growth factor-beta (TGF-beta) superfamily elicited by single applications of each recombinant human bone morphogenetic/osteogenic proteins (BMPs/OPs). Using the calvarium and the rectus abdominis muscle of adult baboons Papio ursinus as a model for tissue induction and morphogenesis, this study investigated the induction of bone morphogenesis by gamma-irradiated hOP-1 delivered by gamma-irradiated bovine insoluble collagenous bone matrix, the hOP-1 osteogenic device, for bone induction in heterotopic and orthotopic sites of the primate Papio ursinus and the expression patterns of OP-1, collagen type IV, BMP-3 and TGFbeta1mRNAs elicited by increasing single applications of doses of the hOP-1 osteogenic devices (0.1, 0.5 and 2.5 mg hOP-1/g of matrix) applied heterotopically in the rectus abdominis muscle and orthotopically in 48 calvarial defects of 12 adult baboons. Histology and histomorphometry on serial undecalcified sections prepared from the specimens harvested on day 15, 30 and 90 showed that all the doses of the hOP-1 osteogenic device induced bone formation culminating in complete calvarial regeneration by day 90. Type IV collagen mRNA expression, a marker of angiogenesis, was strongly expressed in both heterotopic and orthotopic tissues. High levels of expression of OP-1 mRNA demonstrated autoinduction of OP-1 mRNAs. Expression levels of BMP-3 mRNA varied from tissues induced in heterotopic vs. orthotopic sites with high expression in rapidly forming heterotopic ossicles together with high expression of type IV collagen mRNA. The temporal and spatial expressions of TGF-beta1 mRNAindicate a specific temporal transcriptional window during which expression of TGF-beta1 is mandatory for successful and optimal osteogenesis. The induction of bone by hOP-1 in Papio ursinus develops as a mosaic structure with distinct spatial and temporal patterns of gene expression of members of the TGF-beta superfamily that singly, synergistically and synchronously initiate and maintain tissue induction and morphogenesis.
Cowlishaw Guy - One of the best experts on this subject based on the ideXlab platform.
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Immigrant males' knowledge influences baboon troop movements to reduce home range overlap and mating competition
'Oxford University Press (OUP)', 2021Co-Authors: Collet Julien, Baniel Alice, Huchard Elise, Carter Alecia, Pettorelli Nathalie, King Andrew, Lee Alexander, Marshall Harry, Cowlishaw GuyAbstract:International audienceMechanistic models suggest that individuals' memories could shape home range patterns and dynamics, and how neighbours share space. In social species, such dynamics of home range overlap may be affected by the pre-dispersal memories of immigrants. We tested this "immigrant knowledge hypothesis" in a wild population of chacma baboons (Papio ursinus). We predicted that overlap dynamics with a given neighbouring troop's home range should reflect males' adaptive interests in overlap when the alpha male had immigrated from this neighbouring troop but less so when the alpha male originated from elsewhere. We used data collected between 2005 and 2013 on two neighbouring troops in Namibia, comprising GPS records of daily ranges, male natal origins, daily females' reproductive status, and a satellite index of vegetation growth. We found support for our prediction in line with male reproductive strategies but not in line with foraging conditions. In periods with a higher relative number of fertile females over adult males in the focal troop, male baboons would benefit from reducing overlap with their neighbours to mitigate the costs of between-troop mating competition. This was indeed observed but only when the alpha male of the focal troop was an immigrant from that neighbouring troop, and not with alpha males of other origins, presumably due to their different knowledge of the neighbouring troop. Our findings highlight the role of reproductive competition in the range dynamics of social groups, and suggest that spatial segregation between groups could increase through the combination of dispersal and memory
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Birth timing generates reproductive trade-offs in a non-seasonal breeding primate
'The Royal Society', 2021Co-Authors: Dezeure Jules, Cowlishaw Guy, Baniel Alice, Carter Alecia, Godelle Bernard, Huchard EliseAbstract:International audienceThe evolutionary benefits of reproductive seasonality are often measured by a single-fitness component, namely offspring survival. Yet different fitness components may be maximized by different birth timings. This may generate fitness trade-offs that could be critical to understanding variation in reproductive timing across individuals, populations and species. Here, we use long-term demographic and behavioural data from wild chacma baboons (Papio ursinus) living in a seasonal environment to test the adaptive significance of seasonal variation in birth frequencies. We identify two distinct optimal birth timings in the annual cycle, located four-month apart, which maximize offspring survival or minimize maternal interbirth intervals (IBIs), by respectively matching the annual food peak with late or early weaning. Observed births are the most frequent between these optima, supporting an adaptive trade-off between current and future reproduction. Furthermore, infants born closer to the optimal timing favouring maternal IBIs (instead of offspring survival) throw more tantrums, a typical manifestation of mother-offspring conflict. Maternal trade-offs over birth timing, which extend into mother-offspring conflict after birth, may commonly occur in long-lived species where development from birth to independence spans multiple seasons. Our findings therefore open new avenues to understanding the evolution of breeding phenology in long-lived animals, including humans
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Oestrous females avoid mating in front of adult male bystanders in wild chacma baboons
'The Royal Society', 2019Co-Authors: Baniel Alice, Cowlishaw Guy, Delaunay Axelle, Huchard EliseAbstract:International audienceIn social species, female mating strategies can be constrained by both male and female groupmates through sexual conflict and reproductive competition, respectively. This study tests if females adjust their sexual behaviour according to the presence of male and female bystanders in wild chacma baboons (Papio ursinus) and assesses their relative importance. Our results show that oestrous females initiate fewer copulations in the presence of adult male bystanders, irrespective of whether they are mate-guarded or not. This inhibitory effect probably reflects a response to indirect sexual coercion by males, whose close proximity may dissuade females to initiate copulations with rival males to avoid punishment and/or aggressive mating interference. By contrast, females initiate more matings with their mate-guard in the presence of higher-ranking female bystanders, which may reflect an attempt to secure bodyguard services from their mate when they feel threatened. These results emphasize the importance of intra- and intersexual conflicts in shaping female sexual behaviour in this promiscuous society
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Friend or foe: Reconciliation between males and females in wild chacma baboons
'Elsevier BV', 2019Co-Authors: Webb Christine, Cowlishaw Guy, Baniel Alice, Huchard EliseAbstract:International audienceMale aggression towards females is a common and often costly occurrence in species that live in bisexual groups. But preferential heterosexual relationships are also known to confer numerous fitness advantages to both sexes—making it of interest to explore how aggression is managed among male–female dyads through strategies like reconciliation (i.e. postconflict affiliative reunions between former opponents). In this study, we build on the traditional postconflict matched-control (PC-MC), time rule and rate methods to validate a novel methodological approach that tests for the presence and form of reconciliation between male and female wild chacma baboons, Papio ursinus. We show that heterosexual opponents exhibit friendly postconflict reunions, further demonstrating that reconciliation occurs almost exclusively between males and pregnant/lactating females who form tight social bonds. Such ‘friendships’ represent stable associations offering proximate and ultimate benefits to both parties—mainly improving (future) offspring survival. This aligns our findings with the ‘valuable relationship hypothesis’, which predicts rates of reconciliation to increase with the fitness consequences of the opponents' bond. Moreover, patterns concerning the initiative to reconcile reveal that males are as likely as females to initiate reconciliation, suggesting that males play a heretofore underappreciated role in maintaining heterosexual friendships. Beyond proposing a multivariate methodological technique applicable to other long-term observational data sets, the present research illuminates how male–female aggression in promiscuous societies may be mitigated via relationship repair strategies like reconciliation, the balance in those efforts between partners shedding new light on the mutual investment in such bond
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Jealous females? Female competition and reproductive suppression in a wild promiscuous primate
'The Royal Society', 2018Co-Authors: Baniel Alice, Cowlishaw Guy, Huchard EliseAbstract:Female–female competition over paternal care has rarely been investigated in promiscuous mammals, where discreet forms of male care have recently been reported despite low paternity certainty. We investigated female competition over paternal care in a wild promiscuous primate, the chacma baboon (Papio ursinus), where pregnant and lactating females establish strong social bonds (friendships) with males that provide care to their offspring. We tested whether pregnant and lactating females interfere with the sexual activity of their male friend to prevent new conceptions that might lead to the subsequent dilution of his paternal care. We found that pregnant and lactating females were more aggressive towards oestrous females when they had recently conceived themselves, and when the oestrous female was mate-guarded by, and showed greater sexual activity with, their male friend. This aggression also reduced the likelihood of conception of the targeted female. These findings indicate that females can aggressively prevent further conceptions with their offspring's carer through reproductive suppression. Competition over access to paternal care may play an important and underestimated role in shaping female social relationships and reproductive strategies in promiscuous mammalian societies
Guy Cowlishaw - One of the best experts on this subject based on the ideXlab platform.
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exploring individual variation in associative learning abilities through an operant conditioning task in wild baboons
PLOS ONE, 2020Co-Authors: Guy Cowlishaw, Alecia J. Carter, Claudia MartinaAbstract:Cognitive abilities underpin many of the behavioural decisions of animals. However, we still have very little understanding of how and why cognitive abilities vary between individuals of the same species in wild populations. In this study, we assessed the associative learning abilities of wild chacma baboons (Papio ursinus) across two troops in Namibia with a simple operant conditioning task. We evaluated the ability of individuals to correctly associate a particular colour of corn kernels with a distasteful flavour through repeated presentations of two small piles of corn dyed different colours, one of which had been treated with a non-toxic bitter substance. We also assessed whether individual variation in learning ability was associated with particular phenotypic traits (sex, social rank and neophilia) and states (age and prior vigilance). We found no evidence of learning the association either within each trial or across trials, nor any variation based on individuals’ phenotypes. This appeared to be due to a high tolerance for bitter foods leading to similar acceptance of both palatable and unpalatable kernels. Earlier avoidance of the bitter kernels during pilot trials suggests this higher tolerance may have been largely driven by a drought during the experiments. Overall, our findings highlight the potential influence of current environmental challenges associated with conducting cognitive tests of animals in the wild.
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Supplementary Material from Jealous females? Female competition and reproductive suppression in a wild promiscuous primate
2018Co-Authors: Alice Baniel, Guy Cowlishaw, Elise HuchardAbstract:Female–female competition over paternal care has rarely been investigated in promiscuous mammals, where discreet forms of male care have recently been reported despite low paternity certainty. We investigated female competition over paternal care in a wild promiscuous primate, the chacma baboon (Papio ursinus), where pregnant and lactating females establish strong social bonds (friendships) with males that provide care to their offspring. We tested whether pregnant and lactating females interfere with the sexual activity of their male friend to prevent new conceptions that might lead to the subsequent dilution of his paternal care. We found that pregnant and lactating females were more aggressive towards oestrous females when they had recently conceived themselves, and when the oestrous female was mate-guarded by, and showed greater sexual activity with, their male friend. This aggression also reduced the likelihood of conception of the targeted female. These findings indicate that females can aggressively prevent further conceptions with their offspring's carer through reproductive suppression. Competition over access to paternal care may play an important and underestimated role in shaping female social relationships and reproductive strategies in promiscuous mammalian societies
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Personality predicts the propensity for social learning in a wild primate
PeerJ Inc., 2014Co-Authors: Alecia J. Carter, Harry H. Marshall, Robert Heinsohn, Guy CowlishawAbstract:Social learning can play a critical role in the reproduction and survival of social animals. Individual differences in the propensity for social learning are therefore likely to have important fitness consequences. We asked whether personality might underpin such individual variation in a wild population of chacma baboons (Papio ursinus). We used two field experiments in which individuals had the opportunity to learn how to solve a task from an experienced conspecific demonstrator: exploitation of a novel food and a hidden item of known food. We investigated whether the (1) time spent watching a demonstrator and (2) changes in task-solving behaviour after watching a demonstrator were related to personality. We found that both boldness and anxiety influenced individual performance in social learning. Specifically, bolder and more anxious animals were more likely to show a greater improvement in task solving after watching a demonstrator. In addition, there was also evidence that the acquisition of social information was not always correlated with its use. These findings present new insights into the costs and benefits of different personality types, and have important implications for the evolution of social learning
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evaluating animal personalities do observer assessments and experimental tests measure the same thing
Behavioral Ecology and Sociobiology, 2012Co-Authors: Harry H. Marshall, Alecia J. Carter, Robert Heinsohn, Guy CowlishawAbstract:The animal personality literature uses three approaches to assess personality. However, two of these methods, personality ratings and experimentation, have been little compared in captivity and never compared in the wild. We assessed the boldness of wild chacma baboons Papio ursinus using both ratings and experimental methods. Boldness was experimentally assessed when individuals were presented with a novel food item during natural foraging. The boldness of the same individuals was rated on a five-point scale by experienced observers. The ratings and experimental assessments of boldness were found to correlate positively and in a linear fashion. When considered categorically the two approaches showed variable agreement depending on the number of categories assigned and the cut-off criteria adopted. We suggest that the variation between approaches arises because each method captures different aspects of personality; ratings consider personality in absolute terms (using predefined criteria) and multiple contexts, while experimental assessments consider personality in relative terms (using experimental scores relative to the population average) and in limited contexts. We encourage animal personality researchers to consider adopting both methodologies in future studies. We also propose that future studies restrict their analyses to continuous data, since the greatest comparability between methods was found with these data. However, if individuals must be categorised, we suggest that researchers either (a) analyse only those individuals categorised as bold or shy by both ratings and experimental approaches or, if these methods cannot be employed simultaneously, (b) do not use approach-specific criteria but choose a cut-off that can be compared by both approaches.
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the dining etiquette of desert baboons the roles of social bonds kinship and dominance in co feeding networks
American Journal of Primatology, 2011Co-Authors: Andrew J. King, Fay E Clark, Guy CowlishawAbstract:To better understand how individual relationships influence patterns of social foraging in primate groups, we explored networks of co-feeding in wild desert baboons (Papio ursinus). To minimize the risk of aggression and injury associated with contest competition, we expected that individual group members would choose to co-feed with those group-mates that are most likely to show tolerance and a willingness to share food patches. We tested two alternative hypotheses about who those group-mates might be: the “social bonds hypothesis” predicts that preferred foraging partners will be those with whom individuals share strong social bonds, indexed by grooming, whereas the “kinship hypothesis” predicts that preferred foraging partners will be relatives. We also investigated and controlled for the effects of dominance rank, given that competitive ability is known to shape foraging patterns. Social network analyses of over 5,000 foraging events for 14 adults in a single troop revealed that baboon co-feeding was significantly correlated with grooming relationships but not genetic relatedness, and this finding was also true of the female-only co-feeding network. Dominant individuals were also found to be central to the co-feeding network, frequently sharing food patches with multiple group-mates. This polyadic analysis of foraging associations between individuals underlines the importance of dominance and affiliation to patterns of primate social foraging. Am. J. Primatol. 73:768–774, 2011. © 2011 Wiley-Liss, Inc.
Elise Huchard - One of the best experts on this subject based on the ideXlab platform.
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Supplementary Material from Jealous females? Female competition and reproductive suppression in a wild promiscuous primate
2018Co-Authors: Alice Baniel, Guy Cowlishaw, Elise HuchardAbstract:Female–female competition over paternal care has rarely been investigated in promiscuous mammals, where discreet forms of male care have recently been reported despite low paternity certainty. We investigated female competition over paternal care in a wild promiscuous primate, the chacma baboon (Papio ursinus), where pregnant and lactating females establish strong social bonds (friendships) with males that provide care to their offspring. We tested whether pregnant and lactating females interfere with the sexual activity of their male friend to prevent new conceptions that might lead to the subsequent dilution of his paternal care. We found that pregnant and lactating females were more aggressive towards oestrous females when they had recently conceived themselves, and when the oestrous female was mate-guarded by, and showed greater sexual activity with, their male friend. This aggression also reduced the likelihood of conception of the targeted female. These findings indicate that females can aggressively prevent further conceptions with their offspring's carer through reproductive suppression. Competition over access to paternal care may play an important and underestimated role in shaping female social relationships and reproductive strategies in promiscuous mammalian societies
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A rule-of-thumb based on social affiliation explains collective movements in desert baboons
Animal Behaviour, 2011Co-Authors: Andrew King, Elise Huchard, Cédric Sueur, Guy CowlishawAbstract:Animals living in groups will profit most from sociality if they coordinate the timing and nature of their activities. Self-organizing mechanisms can underlie coordination in large animal groups such as insect colonies or fish schools, but to what degree these mechanisms operate in socially complex species that live in small stable groups is not well known. We therefore examined the collective departure of wild chacma baboons, Papio ursinus, from their sleeping sites. First, in line with previous observations, the departure process appeared to be coordinated through the cue of individuals 'moving off', with no role for specific vocal or visual signalling. Second, we employed network analyses to explore how interindividual relationships influenced departure patterns, and found that a local rule, to follow the movements of those baboons with whom they shared a close social affiliation, determined when the baboon group departed. Finally, using an agent-based model, we were able to simulate mathematically the observed patterns of collective movements based upon the emergent rule that we identified. Our study adds weight to the idea that social complexity does not necessitate cognitive complexity in the decisionmaking process, consistent with heuristic decision-making perspectives studied by cognitive psychologists and researchers studying self-organization in biological systems.
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mhc mate choice and heterozygote advantage in a wild social primate
Molecular Ecology, 2010Co-Authors: Elise Huchard, Leslie A Knapp, Jinliang Wang, Michel Raymond, Guy CowlishawAbstract:Preferences for mates carrying dissimilar genes at the major histocompatibility complex (MHC) may help animals increase offspring pathogen resistance or avoid inbreeding. Such preferences have been reported across a range of vertebrates, but have rarely been investigated in social species other than humans. We investigated mate choice and MHC dynamics in wild baboons (Papio ursinus). MHC Class II DRB genes and 16 microsatellite loci were genotyped across six groups (199 individuals). Based on the survey of a key segment of the gene-rich MHC, we found no evidence of mate choice for MHC dissimilarity, diversity or rare MHC genotypes. First, MHC dissimilarity did not differ from random expectation either between parents of the same offspring or between immigrant males and females from the same troop. Second, female reproductive success was not influenced by MHC diversity or genotype frequency. Third, population genetic structure analysis revealed equally high genotypic differentiation among troops, and comparable excess heterozygosity within troops for juveniles, at both Mhc-DRB and neutral loci. Nevertheless, the age structure of Mhc-DRB heterozygosity suggested higher longevity for heterozygotes, which should favour preferences for MHC dissimilarity. We propose that high levels of within-group outbreeding, resulting from group-living and sex-biased dispersal, might weaken selection for MHC-disassortative mate choice.
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dominance and affiliation mediate despotism in a social primate
Current Biology, 2008Co-Authors: Elise Huchard, Andrew J. King, Caitlin Douglas, Nick J B Isaac, Guy CowlishawAbstract:Group-living animals routinely have to reach a consensus decision and choose between mutually exclusive actions in order to coordinate their activities and benefit from sociality [1] and [2]. Theoretical models predict “democratic” rather than “despotic” decisions to be widespread in social vertebrates, because they result in lower “consensus costs”—the costs of an individual foregoing its optimal action to comply with the decision—for the group as a whole [1] and [3]. Yet, quantification of consensus costs is entirely lacking, and empirical observations provide strong support for the occurrence of both democratic and despotic decisions in nature [1], [4] and [5]. We conducted a foraging experiment on a wild social primate (chacma baboons, Papio ursinus) in order to gain new insights into despotic group decision making. The results show that group foraging decisions were consistently led by the individual who acquired the greatest benefits from those decisions, namely the dominant male. Subordinate group members followed the leader despite considerable consensus costs. Follower behavior was mediated by social ties to the leader, and where these ties were weaker, group fission was more likely to occur. Our findings highlight the importance of leader incentives and social relationships in group decision-making processes and the emergence of despotism.
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Molecular study of Mhc-DRB in wild chacma baboons reveals high variability and evidence for transspecies inheritance
Immunogenetics, 2006Co-Authors: Elise Huchard, Michel Raymond, Guy Colishaw, Mylène Weill, L.a. KnappAbstract:The MHC class II genes of many primate species were investigated extensively in recent years. However, while Mhc-DRB genes were studied in Old World monkeys such as rhesus macaques, the Mhc-DRB of baboons was only studied in a limited way. Because of their close anatomical and physiological relationship to humans, baboons are often used as models for reproduction and transplantation research. Baboons are also studied as a model species in behavioural ecology. Thus, identification of MHC genes would provide a foundation for studies of Mhc, biology and behaviour. Here, we describe the use of PCR, cloning, denaturing gradient gel electrophoresis (DGGE) and sequencing to identify Mhc-DRB sequences in wild chacma baboons (Papio ursinus). We amplified the highly variable second exon of baboon Mhc-DRB sequences using generic DRB primers. To validate and optimize the DGGE protocol, four DNA samples were initially studied using cloning and sequencing. Clones were screened using a novel RFLP approach to increase the number of clones identified for each individual. Results from cloning and sequencing were used to optimise DGGE conditions for Mhc-DRB genotyping of the remaining study subjects. Using these techniques, we identified 16 Paur-DRB sequences from 30 chacma baboons. On the basis of phylogenetic tree analyses, representatives of the Mhc- DRB1 and Mhc-DRB5 loci, and 13 different DRB lineages were identified. Evidence for trans-species inheritance of some Mhc-DRB sequences comes from high identity between the new Paur-DRB sequences and sequences from Papio cynocephalus, Macaca mulatta and possibly Galago moholi.
Shirley C. Strum - One of the best experts on this subject based on the ideXlab platform.
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To grunt or not to grunt: Factors governing call production in female olive baboons, Papio anubis
PloS one, 2018Co-Authors: Eila R. Roberts, Veronika Städele, Shirley C. StrumAbstract:Vocal signals often play an important role in synchronizing the activities of group members, coordinating decisions about when and where to travel, and facilitating social interactions in which there are potential conflicts of interest. Here, we show that when female olive baboons (Papio anubis) give low amplitude grunts after approaching other females, they are less likely to behave aggressively toward their partners and more likely to handle their partners' infants and interact affiliatively with them. In addition, females are more likely to grunt after they approach lower ranking females than after they approach higher ranking females and are less likely to grunt after they approach their own mothers and daughters than after they approach other females. These patterns, which are strikingly similar to patterns previously reported in chacma baboons (Papio ursinus) support the hypothesis that grunts function as signals of benign intent. Moreover, they suggest that actors' decisions about whether to grunt or remain silent are influenced by the social context, particularly their partners' likely response to their approach. Taken together, the patterning of grunts in olive and chacma baboon suggests that these vocalizations play an important in reducing uncertainty about actors' intentions and facilitate nonaggressive social interactions.
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female male relationships influence the form of female female relationships in olive baboons Papio anubis
Animal Behaviour, 2017Co-Authors: Joan B Silk, Eila R. Roberts, Brendan J Barrett, Sam K Patterson, Shirley C. StrumAbstract:According to socioecological theory, ecological pressures acting on females play an important role in shaping social organization, dispersal patterns and the nature of female–female relationships. However, there has been relatively little consideration of how females' relationships with males may influence the nature of females' relationships to other females. Here, we show that female olive baboons form well-differentiated relationships with adult males and these ties influence their relationships with other females. As in other species of savanna baboons, female olive baboons show pronounced preferences for close kin, but related females do not often share the same top-ranked male partners. Shared associations with males bring females into more frequent contact with distant kin and nonkin. The combined effects of bringing distantly related and unrelated females together and separating close kin reduced the extent of nepotistic biases among females in the study groups compared to female yellow baboons, Papio cynocephalus, and chacma baboons, Papio ursinus. These data suggest that selective pressures acting on both females and males may influence the nature and function of female–female relationships.
