Institute for Primate Research

Nairobi, Kenya

Institute for Primate Research

Nairobi, Kenya
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Westendorff S.,Institute for Primate Research | Klaes C.,Institute for Primate Research | Gail A.,Institute for Primate Research
Journal of Neuroscience | Year: 2010

Flexible sensorimotor planning is the basis for goal-directed behavior. We investigated the integration of visuospatial information with context-specific transformation rules during reach planning.Wewere especially interested in the relative timing of motor-goal decisions in monkey dorsal premotor cortex (PMd) and parietal reach region (PRR). We used a rule-based mapping task with different cueing conditions to compare task-dependent motor-goal latencies. The task allowed us a separation of cue-related from motor-related activity, and a separation of activity related to motor planning from activity related to motor initiation or execution. The results show that selectivity for the visuospatial goal of a pending movement occurred earlier in PMd than PRR whenever the task required spatial remapping. Such remapping was needed if the spatial representation of a cue or of a default motor plan had to be transformed into a spatially incongruent representation of the motor goal. In contrast, we did not find frontoparietal latency differences if the spatial representation of the cue or the default plan was spatially congruent with the motor goal. The fact that frontoparietal latency differences occurred only in conditions with spatial remapping was independent of the subjects' partial a priori knowledge about the pending goal. Importantly, frontoparietal latency differences existed for motor-goal representations during movement planning, without immediate motor execution.Weinterpret our findings as being in support of the hypothesis that latency differences reflect a dynamic reorganization of network activity in PRR, and suggest that the reorganization is contingent on frontoparietal projections from PMd. Copyright © 2010 the authors.

Nguyen N.,California State University, Fullerton | Gesquiere L.,Princeton University | Alberts S.C.,Duke University | Altmann J.,Princeton University | Altmann J.,Institute for Primate Research
Animal Behaviour | Year: 2012

In mammals, maternal care is essential for offspring survival, yet individual differences in this care can dramatically affect offspring growth and development. Few studies have, however, investigated the sources, magnitude and consequences of naturally occurring interindividual variation in maternal care during the neonatal period. In this study, we examine several hormonal and nonhormonal predictors of naturally occurring variation in the mother-neonate relationship during the first 8. weeks of infancy in 34 wild baboon (. Papio cynocephalus) mother-infant dyads in Amboseli, Kenya. We use data on physical contact and suckling patterns to assess the quality of the mother-neonate relationship and to evaluate the extent to which variation in this relationship is predictable from perinatal ovarian steroids (i.e. faecal oestrogen and progesterone metabolites), previous infant care experience, maternal dominance rank and offspring sex. We found that newborn infants of more experienced mothers initiated higher rates of changes in mother-infant contact than newborns of less experienced mothers. However, at each level of maternal experience, newborn males initiated higher rates of changes in mother-infant contact than newborn females. Moreover, we found evidence suggesting that variation in suckling activity among daughters (but not sons) was predictable from maternal dominance rank and faecal oestrogen (fE) concentrations before birth. To our knowledge, our study provides the first evidence of (1) the influence of cumulative maternal experience on the mother-infant relationship and (2) the emergence of sex differences in the mother-infant relationship during the neonatal period in wild primates. Our results suggest that the well-documented sex differences in life history, behaviour and ecology in primates (and other social mammals) may originate very early in life. © 2012 The Association for the Study of Animal Behaviour.

Markham A.C.,Princeton University | Guttal V.,Princeton University | Guttal V.,Indian Institute of Science | Alberts S.C.,Duke University | And 3 more authors.
Behavioral Ecology and Sociobiology | Year: 2013

Intraspecific competition is a key factor shaping space-use strategies and movement decisions in many species, yet how and when neighbors utilize shared areas while exhibiting active avoidance of one another is largely unknown. Here, we investigated temporal landscape partitioning in a population of wild baboons (Papio cynocephalus). We used global positioning system (GPS) collars to synchronously record the hourly locations of five baboon social groups for ∼900 days, and we used behavioral, demographic, and life history data to measure factors affecting use of overlap areas. Annual home ranges of neighboring groups overlapped substantially, as predicted (baboons are considered non-territorial), but home ranges overlapped less when space use was assessed over shorter time scales. Moreover, neighboring groups were in close spatial proximity to one another on fewer days than predicted by a null model, suggesting an avoidance-based spacing pattern. At all time scales examined (monthly, biweekly, and weekly), time spent in overlap areas was greater during time periods when groups fed on evenly dispersed, low-quality foods. The percent of fertile females in social groups was negatively correlated with time spent in overlap areas only during weekly time intervals. This suggests that broad temporal changes in ecological resources are a major predictor of how intensively overlap areas are used, and groups modify these ecologically driven spacing patterns at short time scales based on female reproductive status. Together, these findings offer insight into the economics of territoriality by highlighting the dynamics of spacing patterns at differing time scales. © 2013 Springer-Verlag Berlin Heidelberg.

Altmann J.,Princeton University | Altmann J.,Institute for Primate Research | Altmann J.,University of Nairobi | Gesquiere L.,Princeton University | And 5 more authors.
Annals of the New York Academy of Sciences | Year: 2010

The pace of reproductive aging has been of considerable interest, especially in regard to the long postreproductive period in modern women. Here we use data for both sexes from a 37-year longitudinal study of a wild baboon population to place reproductive aging within a life history context for this species, a primate relative of humans that evolved in the same savannah habitat as humans did. We examine the patterns and pace of reproductive aging, including birth rates and reproductive hormones for both sexes, and compare reproductive aging to age-related changes in several other traits. Reproductive senescence occurs later in baboon females than males. Delayed senescence in females relative to males is also found in several other traits, such as dominance status and body condition, but not in molar wear or glucocorticoid profiles. Survival, health, and well-being are the product of risk factors in morphological, physiological, and behavioral traits that differ in rate of senescence and in dependence on social or ecological conditions; some will be very sensitive to differences in circumstances and others less so. © 2010 New York Academy of Sciences.

Markham A.C.,Princeton University | Alberts S.C.,Duke University | Alberts S.C.,Institute for Primate Research | Altmann J.,Princeton University | Altmann J.,Institute for Primate Research
Animal Behaviour | Year: 2012

In many social species, competition between groups is a major factor proximately affecting group-level movement patterns and space use and ultimately shaping the evolution of group living and complex sociality. Here we evaluated the factors influencing group-level dominance among five social groups of wild baboons (Papio cynocephalus), in particular focusing on the spatial determinants of dominance and the consequences of defeat. When direct conflict occurred between conspecific baboon groups, the winning group was predicted by differences in the number of adult males in each group and/or groups that had used the areas surrounding the encounter location more intensively than their opponent in the preceding 9 or 12 months. Relative intensity of space use over shorter timescales (3 and 6 months) was a poor predictor of the interaction's outcome. Losing groups, but not winning groups, experienced clear short-term costs. Losing groups used the area surrounding the interaction less following an agonistic encounter (relative to their intensity of use of the area prior to the interaction). These findings offer insight into the influences and consequences of intergroup competition on group-level patterns of space use. © 2012 The Association for the Study of Animal Behaviour.

Galbany J.,Duke University | Galbany J.,University of Barcelona | Altmann J.,Princeton University | Altmann J.,Institute for Primate Research | And 3 more authors.
American Journal of Physical Anthropology | Year: 2011

Teeth represent an essential component of the foraging apparatus for any mammal, and tooth wear can have significant implications for survival and reproduction. This study focuses on tooth wear in wild baboons in Amboseli, southern Kenya. We obtained mandibular and maxillary tooth impressions from 95 baboons and analyzed digital images of replicas made from these impressions. We measured tooth wear as the percent dentine exposure (PDE, the percent of the occlusal surface on which dentine was exposed), and we examined the relationship of PDE to age, behavior, and life history variables. We found that PDE increased significantly with age for both sexes in all three molar types. In females, we also tested the hypotheses that long-term patterns of feeding behavior, social dominance rank, and one measure of maternal investment (the cumulative number of months that a female had dependent infants during her lifetime) would predict tooth wear when we controlled for age. The hypothesis that feeding behavior predicted tooth wear was supported. The percent of feeding time spent consuming grass corms predicted PDE when controlling for age. However, PDE was not associated with social dominance rank or maternal investment. © 2010 Wiley-Liss, Inc.

Markham A.C.,Princeton University | Gesquiere L.R.,Princeton University | Bellenger J.-P.,Princeton Environmental Institute | Bellenger J.-P.,Université de Sherbrooke | And 4 more authors.
American Journal of Primatology | Year: 2011

In immature wild savannah baboons (Papio cynocephalus), we observed symptoms consistent with copper (Cu) deficiency and, more specifically, with a disorder referred to as white monkey syndrome (WMS) in laboratory primates. The objectives of this study were to characterize this pathology, and test three hypotheses that (1) Cu deficiency may have been induced by zinc (Zn) toxicity, (2) it may have been induced by molybdenum (Mo) toxicity, and (3) cumulative rainfall during the perinatal period and particularly during gestation is an ecological factor distinguishing infants afflicted with WMS from non-WMS infants. During 2001-2009, we observed 22 instances of WMS out of a total 377 live births in the study population. Visible symptoms exhibited by WMS infants included whitening of the animal's fur and/or impaired mobility characterized by an apparent "stiffening" of the hindlimbs. Occurrence of WMS did not vary significantly by gender. However, among individuals that survived at least 180 days, WMS males had a significantly lower survivorship probability than non-WMS males. Zn/Cu ratios assessed from hair samples of adult female baboons were higher in females who had produced at least one WMS offspring relative to females who had not had a WMS offspring. This was true even when the hair sample was collected long after the birth of the female's afflicted infant. We consider this potentially indicative of a robust tendency for low Cu levels induced by elevated Zn intake in some individuals. No significant differences of Mo/Cu ratios were observed. Cumulative rainfall during gestation (~179 days) was 50% lower for WMS infants relative to non-WMS infants. In contrast, rainfall for the two classes of infants did not differ in the 180 days before conception or in the 180 days following birth. This finding highlights the importance of prenatal ecological conditions in healthy fetal development with regard to WMS. © 2011 Wiley Periodicals, Inc.

Langoi D.,Institute for Primate Research | Pavone M.E.,Northwestern University | Gurates B.,Firat University | Chai D.,Institute for Primate Research | And 2 more authors.
Fertility and Sterility | Year: 2013

Objective: To determine the effect of inhibiting aromatase activity on endometrial lesion growth and aromatase expression in a baboon model of induced endometriosis. Design: Prospective study. Setting: Primate research institute. Animal(s): Sixteen olive baboons. Intervention(s): Sixteen olive baboons with induced endometriosis were examined with laparoscopy 10 months after disease inoculation. Animals in group 1 (n = 10) were treated with 1.25 mg/d of the aromatase inhibitor (AI) letrozole, and animals in group 2 (n = 6) were given a placebo for a total of 6 months. Main Outcome Measure(s): Total number of endometriotic lesions, morphology, and volume of lesions, as well as semiquantitative reverse transcription-polymerase chain reaction and quantitative polymerase chain reaction for levels of aromatase cytochrome messenger RNA were measured. Ovarian volumes were evaluated before treatment initiation and every 2 months during the study. Result(s): Treatment of group 1 animals with an AI significantly decreased lesion volume from baseline measurements, whereas the placebo-treated animals showed an increase in lesion volume. Aromatase messenger RNA levels in lesions in the AI-treated animals were significantly lower compared with the placebo-treated animals. Ovarian volumes were significantly increased at 6 months of AI treatment compared with pretreatment volumes. Conclusion(s): These findings suggest that suppression of aromatase cytochrome P450 may inhibit the in vivo growth of endometriotic lesions in baboons. ©2013 by American Society for Reproductive Medicine.

PubMed | University of Michigan and Institute for Primate Research
Type: Journal Article | Journal: Pathogens and disease | Year: 2015

Progestin-based contraception may impact womens susceptibility to sexually transmitted infection. We evaluated the effect of the levonorgestrel intrauterine system (LNG-IUS) on cervical persistence of Chlamydia trachomatis (CT) in a baboon model. Female olive baboons (Papio anubis) with or without an LNG-IUS received CT or sham inoculations. CT was detected in cervical epithelium with weekly nucleic acid amplification testing (NAAT) and culture. Presence of the LNG-IUS was associated with prolonged persistence of CT. Median time to post-inoculation clearance of CT as detected by NAAT was 10weeks (range 7-12) for animals with an LNG-IUS and 3 weeks (range 0-12) for non-LNG-IUS animals (P = 0.06). Similarly, median time to post-inoculation clearance of CT by culture was 9 weeks (range 3-12) for LNG-IUS animals and 1.5 weeks (range 0-10) for non-LNG-IUS animals (P = 0.04). We characterized the community structure of the vaginal microbiota with the presence of the LNG-IUS to determine if alterations in CT colonization dynamics were associated with changes in vaginal commensal bacteria. Vaginal swabs were collected weekly for microbiome analysis. Endocervical CT infection was not correlated with alterations in the vaginal microbiota. Together, these results suggest that LNG-IUS may facilitate CT endocervical persistence through a mechanism distinct from vaginal microbial alterations.

PubMed | University of Michigan and Institute for Primate Research
Type: Journal Article | Journal: Journal of medical primatology | Year: 2016

Stress impacts nonhuman primate menstrual cycle length but the impact of quarantine is unknown. A retrospective analysis was performed on cycle data from 31 wild-caught baboons during and following quarantine. Cycling initiated in 94 days (19-181) and length normalized within 4-6 cycles. Quarantine significantly impacts menstrual cycle length.

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