Habitual cave use and thermoregulation in chacma baboons (Papio hamadryas ursinus)

The willingness to utilise caves as shelters is held to have been important to early humans but dependent on pyrotechnology. Despite anecdotal evidence that non-human primates will also exploit caves there has as yet been no detailed account of such exploitation or of the reasons underlying it. Here we provide the first such data, on the frequency and patterning of the use of an underground cave system by baboons (Papio hamadryas)—and show that usage is determined, at least in part, by above-ground temperatures.     

Observations on the ascending aortic fold in two chacma baboons (Papio hamadryas ursinus)

Baboons (Papio) were used to study the ascending aortic fold. The fold was present in two out of 20 hearts examined. Its position and shape was comparable to that observed in human subjects. The principal difference was the absence of paraganglia. The functional role of the baboon fold is unclear.     

Social stressors and coping mechanisms in wild female baboons (Papio hamadryas ursinus)

We examined the social correlates of fecal glucocorticoid (GC) levels in wild female baboons during a period of social and demographic stability. Females' GC levels were not affected by individual attributes such as number of kin or dominance rank, nor could we detect any significant seasonal effects. Instead, GC levels were influenced by behavioral attributes that varied between individuals and within individuals across time. Pregnant and cycling females who received high rates of aggression had higher GC levels than others. In contrast, pregnant and cycling females who received grunts - vocal signals of benign intent - at high frequencies from dominant females had lower GC levels than females who received grunts at lower frequencies. Lactating females showed the opposite trend, apparently as a consequence of the high rate of grunting and intense, unsolicited attention that their infants received from others. All females experienced lower GC levels in months when they concentrated their grooming among a small number of partners than when their grooming was more evenly distributed among many partners. Although GC levels in female baboons are most strongly influenced by events that directly affect their reproductive success, subtle social factors associated with the loss of predictability and control also seem to exert an effect. Loss of control may be mitigated if a female is able to predict others' intentions - for example, if others grunt to her to signal their intentions - and if she is able to express some preference over the timing and identities of her grooming partners.     

Observations on spontaneous pathological lesions in chacma baboons (Papio ursinus)

Some pathological findings made in more than 3000 autopsies on Chacma baboons (Papio ursinus) are reviewed. Diarrhea is frequent among newcomers in the Primate Colony at the University of Stellenbosch and is possibly related to the stress of adaptation to captivity. Strict control of the water balance of sick animals prevents losses. In 63% of diarrheic baboons cortical adrenal necroses were found. About 10% of the autopsied baboons had a cardiomyopathy. In 50% of the baboons with necrotizing cardiomyopathy adrenal cortical necroses were found. In contrast to man, the Chacma baboon deposits inhaled inert dust in small granulomata similar to early cellular lesions of silicosis. Pyelonephritis unrelated to experimental procedures was found in 0.3%. Six cases of chronic glomerulonephritis were encountered. The inclusion of the lower parathyroids in the thyroid must be considered as a normal finding in Chacma baboons; thymic inclusions in the thyroid are more common than in man. On the whole, there are only minor differences in pathological reactions between Chacma baboon and man, but the former is much less resistant to stress than the latter.     

The effect of medroxyprogesterone acetate on behavioural responses of captive female hamadryas baboons (Papio hamadryas)

Female hormonal contraception is considered here as an alternative to vasectomy for population control in social groups of captive hamadryas baboons (Papio hamadryas). While female hormonal contraceptive methods have been successful, behavioural effects of such agents represent a potential welfare concern. This study examined the effect of medroxyprogesterone acetate (MPA; 3.5 mg/kg) on perineal tumescence and behaviour in three social groups (total of 3 males, 22 females) of captive hamadryas baboons. The agent had little effect on social interactions such as grooming relationships, aggression and affiliation (all P > 0.05), but did cause a reduction in sexual behaviour (P < 0.001). Females-mounting-females and females receiving mounting was decreased during MPA treatment compared with the minimal tumescence phase (P < 0.001). Age strongly influenced the contraceptive's duration: there was a significant correlation between age and latency of return to oestrus post-MPA (r = 0.832, P < 0.001) with the latency increasing by 2.61 days per year of age on average. Age also influenced the frequency of behaviours such as affiliation and aggression (P < 0.001 and P = 0.044, respectively). The absence of adverse behavioural effects further supports the use of MPA in the hamadryas baboon, and its potential use in other non-human primates.     

Progressions of adult male chacma baboons (Papio ursinus) in the moremi wildlife reserve

It has been suggested that the sociospatial organization of baboon progressions has a protective function in which the most physically powerful troop members, the adult males, play a key role. This theory implies regularities in adult male progression order for different species of savannah baboons with similar social systems. Quantitative progression data are available from two such similar baboon species, olive and yellow, but not from the third, chacma. The order of movement of 15 adult male chacma baboons was determined from 40 progressions observed at the Moremi Wildlife Reserve, Botswana. The chacma males were most often found in the front sixth of progressions, next most often in the second sixth, and about equally often from there to the rear. As expected from the protection theory, this frontal positioning is consistent with available quantitative data from other species of savannah baboons.     

Intertroop relations of chacma baboon (Papio ursinus)

Intertroop relations among four troops of the chacma baboon population on the Suikerbosrand Nature Reserve, southern Transvaal, South Africa, were studied for 18 months using radiotelemetry. Encounters between troops occurred only rarely and were relatively nonantagonistic in character. Dominance among the four troops was difficult to identify by means of behavior although differences in range quality among the four were marked. The way in which intertroop relations affected the fitness of members of each of the troops was, therefore, unclear. Transfer of individuals from one troop to another was easily accomplished by both males and females and probably negated the effects of differential range quality on individual reproductive fitness.     

Diurnal variations in serum testosterone concentrations of captive adult male chacma baboons (Papio ursinus)

Captive adult male chacma baboons (Papio ursinus) housed with natural lighting exposure and blood sampled at 3-hr intervals showed significant diurnal variations in serum testosterone concentrations. Low mean concentrations were found at 0800 hr approximately 1 hr after sunrise and mean concentrations were their highest at 2000 hr approximately 1 ¼ hr after sunset.     

Dominance relationships among male hamadryas baboons (Papio hamadryas)

The concept of dominance has been shown to be useful in describing and predicting social interactions in group-living animals. However, the dominance relationships among adult hamadryas males (Papio hamadryas) are poorly understood, and systematic data are missing from the literature. This study investigated dominance relationships among male hamadryas baboons by applying novel statistical techniques to systematic detailed data on agonistic interactions. We also analyzed the dominance relationship with male age and evaluated the association between dominance and access to mating partners (i.e. the number of adult females per one-male unit (OMU)), food resources (i.e. monopolization of feeding areas), and greeting interactions. The derived dominance indexes showed that, in general, leader males were dominant over followers, and that dominance ability did not correlate with male age. Individual dominance values were very close to each other, suggesting that dominance relationships among hamadryas males were not very rigid. In addition, dominance values were positively correlated with number of adult females per OMU but not with feeding priority. Finally, greeting interactions occurred more frequently between individuals with similar dominance values and with low levels of dominance decidedness. We suggest the need of further studies, especially in wild populations, to confirm our findings.     

Subtrooping in a chacma baboon (Papio ursinus) population

Subtrooping in two baboon troops at Suikerbosrand, South Africa, was observed during a study of intertroop relations. Individual associations and locations were opportunistically recorded. Subtrooping varied in frequency according to season, being more frequent in the seasons with lower temperatures and food availability. Some subtroops frequented only certain parts of the larger troop range and remained separate from other groups for up to several days. Comparison with reports of subtrooping in other chacma populations reveals the study population to be relatively unique in the seasonality of subtrooping, the consistency of membership and the frequent occurrence of one-male subtroops. Lack of predation coupled with genetic isolation for several generations may have allowed the Suikerbosrand population to increase the efficiency of resource use in the less favorable seasons of the year, especially for less dominant individuals, through subtrooping. Subtrooping appears to be a facultative potential of all baboon species that requires little genetic change to develop.     

Low Y chromosome variation in Saudi-Arabian hamadryas baboons (Papio hamadryas hamadryas)

It is important to characterise the amount of variation on the mammalian Y chromosome in order to assess its potential for use in evolutionary studies. We report very low levels of polymorphism on the Y chromosome of Saudi-Arabian hamadryas baboons, Papio hamadryas hamadryas. We found no segregating sites on the Y, despite sequence analysis of 3 kb noncontiguous intron sequence in 16 males with divergent autosomal microsatellite genotypes, and a further analysis of 1.1 kb intron sequence in 97 males from four populations by SSCP. In addition, we tested seven human-derived Y-linked microsatellites in baboons. Only four of these loci were male-specific and only one was polymorphic in our 97 male sample set. Polymorphism on the Y chromosome of Arabian hamadryas appears to be low compared to other primate species for which data are available (eg humans, chimpanzees and bonobos). Low effective population size (Ne) of paternal genes due to polygyny and female-biased adult sex ratio is a potential reason for low Y chromosome variation in this species. However, low Ne for the Y should be counterbalanced to some extent by the species' atypical pattern of male philopatry and female-biased dispersal. Allelic richness averaged over seven loci was not significantly different between an African and an Arabian population, suggesting that loss of variation during the colonisation of Arabia does not explain low Y variation. Finally, in the absence of nucleotide polymorphism, it is unclear to what extent selection could be responsible for low Y variation in this species.     

Digit Ratios and Dominance in Female Baboons (Papio hamadryas and Papio ursinus)

A growing body of literature suggests that the ratio between the second and fourth digits of the hands (2D:4D ratio) is associated with exposure to prenatal sex hormones in a variety of animals including primates. Female baboons form dominance hierarchies composed of matrilines of related individuals, and the social mechanisms contributing to the structure of these hierarchies have been well studied. We here investigated the relationship between inferred prenatal androgen effects (PAE) and female rank in a captive troop of Hamadryas baboons (Papio hamadryas) with a typical social structure and three captive groups of chacma baboons (Papio ursinus) made up entirely of unrelated orphans. Low 2D:4D ratios (high inferred PAE) were associated with higher-ranking females and high 2D:4D ratios (low inferred PAE) with lower-ranking females in both focal species. This negative correlation between 2D:4D ratio and rank suggests prenatal androgens are linked with the maintenance of female ranks within matrilines in troops with a natural social structure and to the ranks acquired by orphan females.     

Kinda baboons (Papio kindae) and grayfoot chacma baboons (P. ursinus griseipes) hybridize in the Kafue river valley, Zambia

The ranges of small kinda (Papio kindae) and much larger grayfooted chacma (P. ursinus griseipes) baboons adjoin in the Kafue National Park, Zambia. In a visual survey of baboons at 48 sites in the Kafue River drainage we found that, contrary to previous reports, groups at the species interface near the town of Ngoma are phenotypically diverse and presumably formed by multigenerational hybridization. Mitochondrial and/or Y-chromosome genetic markers from fecal samples (N=164) collected at 29 sites support this conclusion. Groups with phenotypic signs of a history of hybridization also had taxon-specific mitochondria and Y-haplotypes from both parental species. Although the distribution of mitochondrial haplotypes largely mirrored that of external phenotypes, a significant proportion of male specimens from grayfoot as well as hybrid groups carried kinda Y-chromosomes, and kinda Y-chromosomes were involved in all observed cases of mitochondrial/Y-chromosome discordance. These observations are consistent with, though they do not prove, a population history in which the range of chacmas and the hybrid zone have advanced at the expense of the kinda range. They also suggest that, unexpectedly, kinda male×chacma female matings are much more common than the reciprocal cross in the ancestry of hybrids. We suggest that distinctive male kinda behavior and the "juvenile" appearance of kinda baboons of both sexes, perhaps combined with obstetric difficulties of a small kinda female carrying the large offspring of a chacma male, may account for this bias.     

Osteopenia and osteoporosis in adult baboons (Papio hamadryas)

BACKGROUND: Little is known about the degree to which baboons, an important animal model in skeletal research, spontaneously experience age-related osteopenia and osteoporosis. METHODS: We measured bone mineral density (BMD) in 667 baboons, assigned T-scores to older animals based on sex-specific young adult reference groups, and compared reproductive history in older females with low BMD to those with normal BMD. RESULTS: Approximately 25% of older baboon females were osteopenic. No females or males were osteoporotic. Neither parity nor interbirth interval spine clearly distinguished low vs. normal BMD groups. Intersite correspondence in low BMD was highest between sites in the same region rather than sites of the same bone type. CONCLUSION: As with humans, osteopenia is common among older females. The absence of osteoporotic animals may be due to colony maintenance resulting in truncation of the aged population and selection for healthier animals in the oldest ranges.     

Detection of Mycobacterium tuberculosis infection in chacma baboons (Papio ursinus) using the QuantiFERON-TB Gold (In-Tube) assay

Background  Early diagnosis of simian tuberculosis (TB) is vital to prevent transmission of this disease. We evaluated the ability of the QuantiFERON-TB Gold (In-Tube Method) assay (QFG-IT) to detect TB in chacma baboons ( Papio ursinus ).
Methods  Fifty-one baboons were tested using the Tuberculin Skin Test (TST) and the QFG-IT. Baboons testing positive, and animals exposed to infected individuals, were euthanised and subjected to necropsy. Selected tissues were processed for histopathology, mycobacterial culture and genetic speciation.
Results  Tuberculosis was confirmed in one TST positive/QFG-IT positive animal and one TST negative/QFG-IT positive animal. One TST positive/QFG-IT negative animal and five TST negative/QFG-IT negative animals were confirmed uninfected following necropsy.
Conclusion  The QFG-IT correctly detected TB in two baboons, including one TST negative individual and correctly identified six baboons as uninfected, including one TST positive individual. The QFG-IT shows promise as a sensitive, specific test for TB in chacma baboons.     

Female dominance and female social relationships among yellow baboons (Papio hamadryas cynocephalus)

Adult females in a female-bonded, cercopithecine species such as baboons are characterized by hierarchically ranked matrilines, i.e., female offspring assume rankings just beneath those of their mothers. In this system of closely ranked matrilines, a female should engage in significantly more affiliative interactions with those individuals who are closely ranked to herself than with those individuals who are more distantly ranked. We examine the hypothesis that females in this troop of feral yellow baboons (Papio hamadryas cynocephalus) who are closely ranked will also show close social affiliation. We collected focal data on 23 feral, adult female subjects (253 possible dyads) over approximately 1 year at the Tana River National Primate Reserve, Kenya. Following Bramblett's [Behav Brain Sci 4: 435, 1981] method of dominance tabulation and utilizing a modified version of Smuts' [Sex and friendship in baboons, Hawthorne: Aldine Publishing Co., 1985] preferred partner index, we describe and compare the dominance matrix and hierarchy, preferred proximity partner and grooming partner sociograms, and the social networks of these 23 focal females. Over 1,400 interactions were utilized in the dominance tabulations, 41 statistically significant proximity partner preferences were documented, and 100 grooming dyads were recorded. We examine both partners' ranks and the presence of an infant as possible factors influencing proximity and grooming partner preferences. We find that in this population there is no direct correspondence between females' ranks and their affiliation partners. Neither proximity nor grooming preferences are consistently predictable from partners' ranks. While proximity preferences were not significantly influenced by the presence of an infant, grooming partner preferences were. Females with infants had more grooming partners and were more often involved in unidirectional grooming relationships as the recipients than were females without infants. We conclude that females' dominance rankings are not good predictors of either proximity partner or grooming partner preferences and that the presence of an infant does have a significant impact on grooming partner preferences in this population.     

Hematology and blood biochemistry in infant baboons (Papio hamadryas)

Although published normative reference standards for hematologic and clinical chemistry measures are available for adult baboons, their applicability to infants has not been addressed. We analyzed these measures in 110 infant baboons (55 females and 55 males) from a large breeding colony at the Southwest Regional Primate Research Center in San Antonio, Texas. The sample consists of olive baboons and olive/yellow baboon hybrids, 1 week to 12 months of age. We produced cross-sectional reference values and examined the effects of age, sex, and subspecies on these variables. Hematology reference ranges for infant baboons are similar to, but wider than, those for adults. Reference ranges for blood biochemistry measures are generally more dissimilar to adults, indicating that for many variables, reference ranges for adult baboons are not adequate for infants. Although sex and subspecies differences are rare, age accounts for more than 10% of the variance in many of the variables.