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.     

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.     

Gastro-intestinal helminth parasites of the chacma baboon, Papio cynocephalus ursinus, from the coastal lowlands of Zululand, South Africa

An examination of 191 faecal samples from Papio cynocephalus ursinus from Mkuzi Game Reserve, Natal, South Africa, has revealed low prevalence rates for a high diversity of gastro-intestinal helminths. This high diversity, including the first evidence for an acanthocephalan infection in South African baboons, is compared to that from montane baboons studied previously.     

Rank and density correlates of inclusive fitness measures in a natural chacma baboon (Papio ursinus) troop

Some demographic characteristics of a group of chacma baboons (Papio ursinus)in a natural environment in northern Botswana were monitored for an 8-year interval. The group size ranged from 73 to 43 individuals. After 3 years at a high density, the group size declined over a 2-year interval, then stabilized again at reduced numbers (−41 %) and biomass (−40%) for over 2 years. The reduction in group size and biomass was followed by an increase in fecundity, greater for high-ranking than for low-ranking females. At the larger group size, survival was lower for infants born to low-ranking than to high-ranking females. Infant survival rates by female rank were equal at the lower density. The mean weight of adult females increased as the density decreased, but there was no correlation between female rank and body mass. We conclude that there is a negative relationship of density to individual condition and reproductive success and that there are fitness advantages to high female rank.     

A-B-O groups of Chacma baboons (Papio ursinus, Kerr) in South Africa

The blood and saliva groups of 51 Chacma baboons (Papio ursinus, Kerr) were determined. The ABO blood group frequencies differed significantly from another subspecies (P. u. ursinus) but they gave a close agreement with the Hardy-Weinberg estimates. Thus the data are compatible with the hypothesis that the saliva groups of baboons are the products of two allelic genes A and B that are inherited in a similar manner to the A and B genes of humans.     

The social interactions of adult conspecifics with an adult XY gonadal dysgenetic chacma baboon (Papio ursinus)

Two separate behavioral studies on an XY gonadal dysgenetic chacma baboon were carried out. In the first experiment the focal subject was treated identically as the control females by her adult male test partners. In contrast to the controls in this experiment the dysgenetic animal reciprocated the agonistic behaviors directed by the males toward her. In the second study intact and castrated males as well as ovariectomized females served as controls for the dysgenetic subject in tests with ovariectomized adult females. The stimulus females presented more to both classes of males than either the subject females or the gonadal dysgenetic individual, suggesting that the focal subject was treated by other female conspecifics as a female.     

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 effects of captivity stress on the blood chemical values of the chacma baboon (Papio ursinus).

Baboons were trapped and transported to the colony within 3 days of being captured. Blood was collected on Tuesdays and Fridays for blood chemical determinations. The changes in albumin and globulin resulted in marked changes in the albumin: globulin ratio. Cholesterol values showed a sudden and marked drop and the values were still below normal at the end of 9 weeks. Blood sugar values increased to significantly elevated levels and marked changes occurred in the enzyme activity and plasma corticosteroid activity. Male and female animals differed in their response with regard to the values found in some parameters. A period of adaptation or conditioning of 8 weeks was found to be required for an animal to reach stability in its blood chemical values.     

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.     

The glomerular filtration rate,effective renal plasma flow,and renal blood flow in the adult male chacma baboon (Papio ursinus)

Abstract: The radionuclide determination of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) has been validated in man, but not in the primate. GFR, ERPF, and renal blood flow (RBF) were measured in a group of 12 adult male chacma baboons using radiopharmaceuticals. GFR was determined using ^99mtechnetium-labelled diethylenetriamine-pentacetic acid. ERPF was measured with ¹³¹iodine-labelled hippuran. RBF, body surface area, and kidney weights were calculated using standard formulae. GFR was 49 ± 11 ml/min and ERPF was 237.9 ± 54.2 ml/min. Calculated RBF was 430.7 ± 111.9 ml/min and 507.4 ± 138.4 ml/min/100g of renal tissue. The results are in agreement with those obtained using more laborious nonradioisotopic techniques such as para-aminohippurate (PAH) and creatinine clearance and could serve as baseline normal values in the adult male chacma baboon.     

An experimental examination of the colour component in visually mediated sexual arousal of the male chacma baboon (Papio ursinus)

Male chacma baboon ( Papio ursinus ) sexual arousal response as gauged by the coagulated seminal emissions resultant from masturbatory activity was experimentally assessed. Males were initially exposed to an ovariectomized female prior to and during daily oestradiol benzoate treatment. Males were then re-exposed to the same female prior to and during the wearing of a thermoplastic model of a swollen female perineum. A total of eight different colours were sequentially applied to the model. It was only the red model that elicited a response similar to that shown to the oestradiol-treated female. The behavioural data collected from the stimulus female supported the view that it was model colour that determined the differential male response.     

Female perineal swelling and its effects on male sexual arousal: An apparent sexual releaser in the chacma baboon (Papio ursinus)

The function of the periodic perineal swelling that females of some primate species show in relation to their menstrual cycle has long puzzled many scientists. A role in female attractiveness was suspected, but fluctuations in female behaviors concomitant to these changes in female appearance have always prevented its assessment. By attaching a plastic reproduction of a fully swollen perineum to ovariectomized female chacma baboons, it has finally been demonstrated that the sexual swelling hasan important function in the sexual communication of this species. It induces sexual arousal in male conspecifics. The way the perineal swelling acts and other characteristic aspects of this feature appear to qualify it as a releaser for sexual behavior.     

Behavioural and hormonal responses to predation in female chacma baboons (Papio hamadryas ursinus)

In humans, bereavement is associated with an increase in glucocorticoid (GC) levels, though this increase can be mitigated by social support. We examined faecal GC levels and grooming behaviour of free-ranging female baboons to determine whether similar effects were also evident in a non-human species. Females who lost a close relative experienced a significant increase in GC levels in the weeks following their relative's death compared with the weeks before, whereas control females showed no such increase. Despite the fact that females concentrate much of their grooming on close kin, females who lost a close female relative did not experience a decrease in grooming rate and number of grooming partners; instead, both grooming rate and number of grooming partners increased after a relative's death. While the death of a close relative was clearly stressful over the short term, females appeared to compensate for this loss by broadening and strengthening their grooming networks. Perhaps as a result, females' GC levels soon returned to baseline. Even in the presence of familiar troop-mates and other relatives, females experienced a stress response when they lost specific companions, and they apparently sought to alleviate it by broadening and strengthening their social relationships.     

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.     

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.     

Nasogastric intubation technique for bile sampling in the baboon (Papio ursinus).

A duodenal tube was introduced into the duodenum of the fasted baboon via the nasal passage. After the application of vacuum for several minutes, the baboon received an intravenous injection of pancreozymin and cholecystokinin which caused contraction of the gall bladder. Aspiration of the bile sample was carried out via the duodenal tube.