Cercocebus Torquatus Research Articles

A novel, divergent simian T-cell lymphotropic virus type 3 in a wild-caught red-capped mangabey (Cercocebus torquatus torquatus) from Nigeria.

We present here a novel, distinct simian T-cell lymphotropic virus (STLV) found in a red-capped mangabey (Cercocebus torquatus) (CTO-NG409), wild-caught in Nigeria, that showed an HTLV-2-like Western blot (WB) seroreactivity. The complete genome (8920 bp) of CTO-NG409 STLV was related to but different from STLV-3/PHA-PH969 (13.5 %) and STLV-3/PPA-F3 (7.6 %), and STLV-3/CTO604 (11.3 %), found in Eritrean and Senegalese baboons, and red-capped mangabeys from Cameroon, respectively. Phylogenetic analysis of a conserved tax (180 bp) sequence and the env gene (1482 bp) confirmed the relatedness of STLV-3/CTO-NG409 to the STLV-3 subgroup. Molecular clock analysis of env estimated that STLV-3/CTO-NG409 diverged from East and West/Central African STLV-3s about 140,900+/-12,400 years ago, suggesting an ancient African origin of STLV-3. Since phylogenetic evidence suggests multiple interspecies transmissions of STLV-1 to humans, and given the antiquity and wide distribution of STLV-3 in Africa, a search for STLV-3 in human African populations with HTLV-2-like WB patterns is warranted.

Food competition in captive female sooty mangabeys (Cercocebus torquatus atys).

We studied the social and foraging behavior of two captive groups of sooty mangabeys under two different spatial food situations. These food conditions were clumped (food was placed in a box) and dispersed (food was dispersed over the entire enclosure). In each group five adult females and two adult males were observed. As a criterion for food competition, individual differences in the relative food intake were used. Adult female mangabeys had a linear, stable, and unidirectional dominance hierarchy. Access to food was rank dependent among females only under clumped food distribution, as current models of the evolution of primate social systems predict. However, feeding success appeared to be mediated not by female but by male agonistic behavior toward females. High-ranking females received relatively less aggression from males and could, therefore, stay and feed longer in the feeding area. Male tolerance of higher-ranking females seems to mediate female feeding success under restricted food resources. The establishment of a special relationship with a high-ranking male might, therefore, be a strategy to get better access to food. This study demonstrates that female competition for access to food should not be analyzed separately from male influences on females and suggests that a more integral role of males in socioecological models of the evolution of primate social systems should be considered.

Van Schaik’s Socioecological Model : Developments and Problems

van Schaik’s socioecological model (van Schaik, 1989) hypothesized that predation risk and food distribution determine female gregariousness and their social relationships through the type of food competition females experience. Also, it predicts that the distribution of males is dependant upon female gregariousness. This model was later modified by van Schaik and colleagues (Sterck et al., 1997). The modified model incorporated ’habitat saturation’ and ’infanticide risk’ as selective forces to explain several phenomena that van Schaik’s classical model did not. At present, the main focus of the discussion in primate socioecology has shifted to ’infanticide risk’.We review here the evidence for and against van Schaik’s classical and modified models, and point out the following problems to be solved. 1) The modified model cannot be a socioecological model until it is combined with the classical model mainly because it does not address the determining factors of each type of food competition (i.e., food distribution). 2) Out of four social categories addressed in the modified model (Dispersal-Egalitarian, Resident-Nepotistic, Resident-Egalitarian and Resident-Nepotistic-Tolerant), the ecological factors of RNT do not seem valid. In our opinion, RNT is expected where primates equally subsist on both types of food: a) high quality, scattered patches large enough to accommodate all group members, and b) high quality patches that are too small to accommodate all group members. 3) In RE and RNT categories, there is not yet enough evidence to prove either the relationship between food distribution and food competition or the relationship between food competition and social category. 4) The sooty mangabey (Cercocebus torquatus atys) may be categorized into the fifth category (Female-Resident-Despotic) but this may not be explained by ’habitat saturation’ as incorporated into the modified model. If so, ecological factors of FRD should be investigated in more detail. 5) There is little evidence that dispersed females in DE species choose males with a greater ability to defend against infanticide, although high infanticide risk forces females to permanently associate with males as the modified model hypothesizes. 6) Female dispersal in most DE species seems to reduce infanticide risk since larger female groups are more attractive to incoming males. However, we should not jump to conclusions because convincing counter-evidence exists. That is, groups with a larger number of females are more successful than groups with fewer females in reducing infanticide through defensive female coalitions.

Identification of trypanosomes in wild animals from southern Cameroon using the polymerase chain reaction (PCR).

One possible explanation of the maintenance of many historical foci of sleeping sickness in Central Africa could be the existence of a wild animal reservoir. In this study, PCR was used to detect the different trypanosome species present in wild animal captured by hunters in the southern forest belt of Cameroon (Bipindi). Trypanosomes were also detected by a parasitological method (Quantitative buffy coat: QBC). Parasite could not be isolated in culture medium (Kit for in vitro isolation: KIVI). Specific primers of T. brucei s.l., T. congolense forest type, T. congolense savannah type, T. vivax, T. simiae and T. b. gambiense group 1 were used to identify parasites in the blood of 164 animals belonging to 24 different species including ungulates, rodents, pangolins, carnivores, reptiles and primates. Of the 24 studied species, eight were carrying T. b. gambiense group 1. Those parasites pathogenic to man were found in monkeys (Cercocebus torquatus and Cercopithecus nictitans), in ungulates (Cephalophus dorsalis and C. monticola), in carnivores (Nandinia binotata and Genetta servalina) and in rodents (Cricetomys gambianus and Atherurus africanus). 13 species (54%) were carrying T. brucei s.l. identified as non-gambiense group 1.

Distribution, population density, and status of sympatric cercopithecids in the Campo-Ma'an area, Southwestern Cameroon.

A study on species composition, distribution, and population density of cercopithecids in the Campo-Ma'an area, Southwestern Cameroon, was undertaken from December 1997 until August 2000. A total of 665.5 km of line transects was used for the census. Thirteen diurnal primate species including five endangered species (Gorilla g. gorilla, Pan troglodytes, Mandrillus sphinx, Colobus satanas, Cercocebus torquatus) were recorded in the Campo Forest, the greatest part of which is a logging concession. Cercopithecus nictitans (1.43 groups/km2), C. cephus (1.13 groups/km2), C. pogonias (0.81 groups/km2), and C. torquatus (0.51 groups/km2) occurred at medium frequencies compared to figures from other Central African study sites. Mandrill densities estimated (0.27 groups/km2) show that the area is very important for the conservation of this rare species. Guenon densities found inside areas with a high level of human activities did not differ significantly from densities estimated in areas with a lower level of human activities. C. torquatus densities were significantly higher in the areas with a low level of human disturbance and encounter rates with Lophocebus albigena also indicate a preference of less disturbed areas. Mangabeys are thus likely to be adversely affected by human activities in the area. In the Ma'an Forest, which has not been logged yet, ten species were confirmed. The population densities of two guenons (C. nictitans and C. cephus) were estimated to be twice as high in the unlogged forest area as compared to the logged forest of Campo. Other species are rarer in the Ma'an Forest than in the Campo Forest. Although mangabeys are adversely affected by human activities, the results still indicate that selective logging may be compatible with the conservation of cercopithecids, if a reduced damage logging concept and antipoaching measures are implemented. Increased hunting activities following logging operations will definitely have a negative longterm impact on primate populations in the Campo-Ma'an area if no further, more effective conservation measures will regulate wildlife use in future.

Complete sequence of a novel highly divergent simian T-cell lymphotropic virus from wild-caught red-capped mangabeys (Cercocebus torquatus) from Cameroon: a new primate T-lymphotropic virus type 3 subtype.

Among 65 samples obtained from a primate rescue center located in Cameroon, two female adult red-capped mangabeys (Cercocebus torquatus) (CTO-602 and CTO-604), of wild-caught origin, had a peculiar human T-cell lymphotropic virus type 2 (HTLV-2)-like Western blot seroreactivity (p24, RGD21, +/-K55). Analyses of the simian T-cell lymphotropic virus type 3 (STLV-3)/CTO-604 complete proviral sequence (8,919 bp) indicated that this novel strain was highly divergent from HTLV-1 (60% nucleotide similarity), HTLV-2 (62%), or STLV-2 (62%) prototypes. It was, however, related to STLV-3/PH-969 (87%), a divergent STLV strain previously isolated from an Eritrean baboon. The STLV-3/CTO-604 sequence possesses the major open reading frames corresponding to the structural, enzymatic, and regulatory proteins. However, its long terminal repeat is shorter, with only two 21-bp repeats. Furthermore, as demonstrated by reverse transcriptase PCR, this new STLV exhibits significant differences from STLV-3/PH-969 at the mRNA splice junction position level. In all phylogenetic analyses, STLV-3/CTO-604 and STLV-3/PH-969 clustered in a highly supported single clade, indicating an evolutionary lineage independent from primate T-lymphotropic virus type 1 (PTLV-1) and PTLV-2. Nevertheless, the nucleotide divergence between STLV-3/PH-969 and STLV-3/CTO-604 is equivalent to or higher than the divergence observed between the different HTLV-1 or HTLV-2 subtypes. Thus, the STLV-3/CTO-604 strain can be considered the prototype of a second subtype in the PTLV-3 type. The presence of two related viruses in evolutionarily distantly related African monkeys species, living in two opposite ecosystems (rain forest versus desert), reinforces the possible African origin of PTLV and opens new avenues regarding the search for a possible human counterpart of these viruses in individuals exhibiting such HTLV-2-like seroreactivities.

Characterization of novel simian immunodeficiency viruses from red-capped mangabeys from Nigeria (SIVrcmNG409 and -NG411).

Two novel simian immunodeficiency virus (SIV) strains from wild-caught red-capped mangabeys (Cercocebus torquatus torquatus) from Nigeria were characterized. Sequence analysis of the fully sequenced SIV strain rcmNG411 (SIVrcmNG411) and gag and pol sequence of SIVrcmNG409 revealed that they were genetically most closely related to the recently characterized SIVrcm from Gabon (SIVrcmGB1). Thus, red-capped mangabeys from distant geographic locations harbor a common lineage of SIV. SIVrcmNG411 carried a vpx gene in addition to vpr, suggesting a common evolutionary ancestor with SIVsm (from sooty mangabeys). However, SIVrcm was only marginally closer to SIVsm in that region than to any of the other lentiviruses. SIVrcm showed the highest similarity in pol with SIVdrl, isolated from a drill, a primate that is phylogenetically distinct from mangabey monkeys, and clustered with other primate lentiviruses (primarily SIVcpz [from chimpanzees] and SIVagmSab [from African green monkeys]) discordantly in different regions of the genome, suggesting a history of recombination. Despite the genetic relationship to SIVcpz in the pol gene, SIVrcmNG411 did not replicate in chimpanzee peripheral blood mononuclear cells (PBMC), although two other viruses unrelated to SIVcpz, SIVmndGB1 (from mandrills) and SIVlhoest (from L'Hoest monkeys), were able to grow in chimpanzee PBMC. The CCR5 24-bp deletion previously described in red-capped mangabeys from Gabon was also observed in Nigerian red-capped mangabeys, and SIVrcmNG411, like SIVrcmGB1, used CCR2B and STRL33 as coreceptors for virus entry. SIVrcm, SIVsm, SIVmndGB1, and all four SIVlhoest isolates but not SIVsun (from sun-tailed monkeys) replicated efficiently in human PBMC, suggesting that the ability to infect the human host can vary within one lineage.

Molecular and phylogenetic analyses of 16 novel simian T cell leukemia virus type 1 from Africa: close relationship of STLV-1 from Allenopithecus nigroviridis to HTLV-1 subtype B strains.

A serological survey searching for antibodies reacting with human T-cell leukemia virus type 1 (HTLV-1) antigens was performed on a series of 263 sera/plasma obtained from 34 monkey species or subspecies, originating from different parts of Africa. Among them, 34 samples exhibited a typical HTLV-1 Western blot pattern. Polymerase chain reaction was performed with three primer sets specific either to HTLV-1/STLV-1 or HTLV-2 and encompassing gag, pol, and tax sequences, on genomic DNA from peripheral blood mononuclear cells of 31 animals. The presence of HTLV-1/simian T-cell leukemia virus type 1 (STLV-1) related viruses was determined in the 21 HTLV-1 seropositive animals tested but not in the 10 HTLV-1 seronegative individuals. Proviral DNA sequences from the complete LTR (750 bp) and a portion of the env gene (522 bp) were determined for 16 new STLV-1 strains; some of them originating from species for which no STLV-1 molecular data were available as Allenopithecus nigroviridis and Cercopithecus nictitans. Comparative and phylogenetic analyses revealed that these 16 new sequences belong to five different molecular groups. The A. nigroviridis STLV-1 strains exhibited a very strong nucleotide similarity with HTLV-1 of the subtype B. Furthermore, four novel STLV-1, found in Cercocebus torquatus, C. m. mona, C. nictitans, and Chlorocebus aethipos, were identical to each other and to a previously described Papio anubis STLV-1 strain (PAN 503) originating from the same primate center in Cameroon. Our data extend the range of the African primates who could be permissive and/or harbor naturally STLV-1 and provide new evidences of cross-transmission of African STLV-1 between different monkey species living in the same environment and also of STLV-1 transmissions from some monkeys to humans in Central Africa.

Wild Mandrillus sphinx are carriers of two types of lentivirus.

Mandrillus sphinx, a large primate living in Cameroon and Gabon and belonging to the Papionini tribe, was reported to be infected by a simian immunodeficiency virus (SIV) (SIVmndGB1) as early as 1988. Here, we have identified a second, highly divergent SIVmnd (designated SIVmnd-2). Genomic organization differs between the two viral types; SIVmnd-2 has the additional vpx gene, like other SIVs naturally infecting the Papionini tribe (SIVsm and SIVrcm) and in contrast to the other SIVmnd type (here designated SIVmnd-1), which is more closely related to SIVs infecting l'hoest (Cercopithecus lhoesti lhoesti) and sun-tailed (Cercopithecus lhoesti solatus) monkeys. Importantly, our epidemiological studies indicate a high prevalence of both types of SIVmnd; all 10 sexually mature wild-living monkeys and 3 out of 17 wild-born juveniles tested were infected. The geographic distribution of SIVmnd seems to be distinct for the two types: SIVmnd-1 viruses were exclusively identified in mandrills from central and southern Gabon, whereas SIVmnd-2 viruses were identified in monkeys from northern and western Gabon, as well as in Cameroon. SIVmnd-2 full-length sequence analysis, together with analysis of partial sequences from SIVmnd-1 and SIVmnd-2 from wild-born or wild-living mandrills, shows that the gag and pol regions of SIVmnd-2 are closest to those of SIVrcm, isolated from red-capped mangabeys (Cercocebus torquatus), while the env gene is closest to that of SIVmnd-1. pol and env sequence analyses of SIV from a related Papionini species, the drill (Mandrillus leucophaeus), shows a closer relationship of SIVdrl to SIVmnd-2 than to SIVmnd-1. Epidemiological surveys of human immunodeficiency virus revealed a case in Cameroon of a human infected by a virus serologically related to SIVmnd, raising the possibility that mandrills represent a viral reservoir for humans similar to sooty mangabeys in Western Africa and chimpanzees in Central Africa.

Facial growth and the ontogeny of morphological variation within and between the primates Cebus apella and Cercocebus torquatus

AbstractDifferences in facial skeletal form arise in part through differences in growth and in part through differences in embryonic patterning and proportioning. This study examines post‐natal facial growth, sexual dimorphism and adult differences within and between two primate species: Cebus apella and Cercocebus torquatus. The species were chosen because they are phylogenetically distant yet present roughly similar adult morphologies. The comparison of ontogenetic, sexual and phylogenetic differences between these species illuminates the relationship between pre‐natal proportioning, growth, sexual dimorphism and evolutionary change in the facial skeleton.The quantitative analytical methods used in this study are taken from the geometric morphometric toolkit. Additionally, facial growth is examined through scanning electron microscope studies of bone growth remodelling. The main findings are that adult sexual dimorphism differs markedly between the studied species. In both species, however, it arises through extension in males relative to females of a common size–shape growth trajectory plus late divergence of growth between the sexes. This similarity contrasts with the findings that growth remodelling in the facial skeleton and size‐related shape changes in the face of each species differ. Thus, variations in facial form between species seem to be the result of pre‐natally established differences in form plus post‐natal growth divergence, whilst the different sexual dimorphisms of these species arise through the action of similar growth processes on divergent growth trajectories. The implications of these findings for the interpretation of adult variations in facial form and growth are considered.

Allogrooming behavior inCercocebus torquatus: The case for the hygienic functional hypothesis.

The hygienic functional hypothesis of allogrooming behavior was examined in two captive groups (N=9 andN=8) of white-crowned mangabeys (Cercocebus torquatus lunulatus) by analyzing: (1) the corporal distribution of manipulation type according to hair density, and (2) the corporal distribution of allogrooming according to presence of wounds. In both groups the sites with higher hair density received more bouts of Superficial Grooming, which implies a tactile screening of a fragment of the body surface. Only one group tended to emit more allogrooming on the body sites when they were wounded. In the other group, however, the number of wounds was very small and the wounds concentrated predominantly on those sites which were accessible to the subject itself. Thus, our results may be consistent with the hygienic functional hypothesis of allogrooming behavior in general and with the sanitary one in particular.

Functional Implications of Allogrooming in Cercocebus torquatus

We examined the hygienic functional hypothesis of allogrooming in two captive groups (N = 9 and N = 8) of white-crowned mangabeys (Cercocebus torquatus lunulatus) by analyzing the corporeal distribution of allogrooming solicitations according to the variable degree of accessibility of the various body sites. We used focal-animal sampling and continuous recording and nonparametric statistics (sing test and χ2). The fact that in both groups more allogrooming was solicited to sites associated with accessibility problems is consistent with the hygienic functional hypothesis of allogrooming. In any case, there are two facts that suggest that this hypothesis cannot account for all the characteristics of such behavior: 1) the strong distributional selectivity shown by allogrooming solicitations—they concentrated primarily on dorsal and caudal regions instead of those difficult to reach or inaccessible on the whole—and 2) the significant role played by sex in the intragroup distribution of anogenital solicitations. Supporting the multifunctional nature of allogrooming, we find very appealing the ritualization hypothesis, according to which the allogrooming performed on certain body sites would have acquired a sociocommunicative meaning.

Does allogrooming serve a hygienic function in Cercocebus torquatus lunulatus?

To test the hygienic functional hypothesis of allogrooming in the white-crowned mangabey (Cercocebus torquatus lunulatus), we analyzed the distribution of such behavior over the body surface in the individuals of two captive groups of this species (N = 9 and N = 8). To sample the data, we used focal animal sampling and continuous recording. Before analyzing the data, we measured a representative subject in order to calculate the body surface area occupied by each site, defined accessibility rigorously (distinguishing among three categories of sites: easy to reach, difficult to reach, and inaccessible), and tested empirically the classification proposed. To determine whether allogrooming was likely to concentrate on the body sites with accessibility problems, we ran three successive analyses, each of with was increasingly specific: grouping types of sites, analyzing each site separately, and analyzing each subject's reception profile. The results obtained show that in both groups inaccessible sites received more allogrooming than predicted by their actual surface area; sites that were difficult to reach received an amount of allogrooming proportional to the body surface area they occupied, and those easy to reach received less allogrooming than expected. This complementarity between the distribution of auto- and allogrooming is consistent with the hygienic functional hypothesis of allogrooming. However, not all inaccessible sides nor those difficult-to-reach were allogroomed equally: Allogrooming concentrated primarily on dorsal and caudal regions, whose care is incompatible with a ventral/ventral orientation between groomer and groomee. The strong distributional selectivity of allogrooming and the interindividual variability in preferred allogrooming sites suggest that the hygienic functional hypothesis cannot fully account for all the aspects of the corporal distribution of such behavior. Thus, in support of the multifunctional nature of allogrooming, we conclude that there must be more than cleaning involved in Cercocebus torquatus lunulatus' allogrooming.

Patterns of Social Visual Attention in the Red-Capped Mangabey (Cercocebus torquatus torquatus) in the Context of Food Competition

Patterns of Social Visual Attention in the Red-Capped Mangabey (Cercocebus torquatus torquatus) in the Context of Food Competition

Serum concentrations of lipids, vitamins A and E, vitamin D metabolites, and carotenoids in nine primate species at four zoos

The purpose of this work was to measure important nutritional status parameters for captive primates, compare those with published data, and look for a link with diet. The nutritional status of nine captive primate species was examined using biochemical analysis. The species were spider monkeys (Ateles geoffroyi), colobus monkeys (Colobus guereza), sooty mangabeys (Cercocebus torquatus), Schmidt's monkeys (Cercopithecus ascanius), mandrills (Papio sphinx), baboons (Papio cynocephalus), chimpanzees (Pan troglodytes), orangutans (Pongo pygmaeus), and gorillas (Gorilla gorilla). Diet information was collected by survey and the estimated nutritional composition of the diet for each species at each institution was compared with non-human primate nutrient requirements. On the average, the captive primates received diets that met or exceeded recommended dietary guidelines for vitamins A, D, and E for non-human primates. Blood samples were collected from 94 primates held at Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park and analyzed for lipids, vitamins A and E, D metabolites, and carotenoids. Several species showed differences among zoos for some nutrients, but values from any one zoo were not consistently lower. When monkeys were compared with great apes, monkeys had lower serum total cholesterol, triacylglyceride, and measured LDL cholesterol levels, but significantly higher vitamin D metabolite levels. Species differences were found for serum A, E, and carotenoid levels (with the exception of lycopene). Some differences were seen in serum retinol, retinyl palmitate and γ-tocopherol. The relatively large number of animals contributing to this database and the fact that the data were collected from four zoos provide a substantial base for comparing nutritional status. Comparisons of these serum levels with previously published values for selected primates and humans revealed some differences. Zoo Biol 18:551–564, 1999. © 1999 Wiley-Liss, Inc.

Serum concentrations of lipids, vitamins A and E, vitamin D metabolites, and carotenoids in nine primate species at four zoos

The purpose of this work was to measure important nutritional status parameters for captive primates, compare those with published data, and look for a link with diet. The nutritional status of nine captive primate species was examined using biochemical analysis. The species were spider monkeys (Ateles geoffroyi), colobus monkeys (Colobus guereza), sooty mangabeys (Cercocebus torquatus), Schmidt's monkeys (Cercopithecus ascanius), mandrills (Papio sphinx), baboons (Papio cynocephalus), chimpanzees (Pan troglodytes), orangutans (Pongo pygmaeus), and gorillas (Gorilla gorilla). Diet information was collected by survey and the estimated nutritional composition of the diet for each species at each institution was compared with non-human primate nutrient requirements. On the average, the captive primates received diets that met or exceeded recommended dietary guidelines for vitamins A, D, and E for non-human primates. Blood samples were collected from 94 primates held at Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park and analyzed for lipids, vitamins A and E, D metabolites, and carotenoids. Several species showed differences among zoos for some nutrients, but values from any one zoo were not consistently lower. When monkeys were compared with great apes, monkeys had lower serum total cholesterol, triacylglyceride, and measured LDL cholesterol levels, but significantly higher vitamin D metabolite levels. Species differences were found for serum A, E, and carotenoid levels (with the exception of lycopene). Some differences were seen in serum retinol, retinyl palmitate and γ-tocopherol. The relatively large number of animals contributing to this database and the fact that the data were collected from four zoos provide a substantial base for comparing nutritional status. Comparisons of these serum levels with previously published values for selected primates and humans revealed some differences. Zoo Biol 18:551–564, 1999. © 1999 Wiley-Liss, Inc.

COST-BENEFIT ANALYSIS OF ALLOGROOMING BEHAVIOUR IN CERCOCEBUS TORQUATUS LUNULATUS

Abstract We assume that allogrooming is an activity which yields various benefits to the participants and at the same time its practice requires a resource investment. In this work we aim to quantify the costs and benefits derived for each subject by performing allogrooming in order to find the maximum net benefit gained and the equilibrium point above which a major allogrooming investment would not increase the benefits obtained. The data were obtained observing the members of a captive troop (N = 9) of white crowned mangabeys (Cercocebus torquatus lunulatus) at the Barcelona Zoo. Allogrooming time and the preceding and following context were recorded for each actor. The costs were quantified as the energetic expenditure required to perform allogrooming as proposed by Coelho (1974). The benefits were estimated from the frequency and duration of bouts associated to transitions preceded by an agonistic context and followed by a neutral context. The equilibrium values of time spent in allogrooming, for which the costs equalled the benefits, and the value for time invested corresponding to maximal net benefits, were estimated from the theoretical model adjusted to the data. It was found that the differences between the equilibrium point and the maximal net benefit were correlated with the age of the subject, which can be understood as an effect of learning the relation cost-benefit of allogrooming to maintain low levels of agonism within the troop.

Estrus Vocalizations in Two Primate Species (Cercocebus Torquatus Atys and Macaca Nemestrina)

Vocalizations of sexually receptive females in two primate species, the sooty mangabey (Cercocebus torquatus atys) and the pigtail macaque (Macaca nemestrina), were compared with respect to the acoustical features of calls as well as the reproductive and social factors that were associated with calling behavior. Sixty-two bouts of calling were recorded from 18 different pigtail macaque females (mean number of bouts per individual-3.48, SD = 2.17, range 1-7) over a six month period; 19.4% occurred during copulation with males, 25.8% were recorded within 30 seconds after copulation has ceased, while the majority, 54.8%, were not associated with mating. The mangabey group yielded 52 bouts from 18 different females (mean number of bouts per individual = 2.89, SD = 2.47, range 1-10) over a comparable period of time; all 52 mangabey bouts were recorded from females during copulation with males. Calls in both species were highly stereotyped and were not acoustically similar to other vocalizations in the species' repertoire; the acoustical structure of the calls of both species, with most energy distributed at relatively low frequencies, suggests adaptations for propagation over distance. Dominance rank of the caller was associated with significant variation in calling by estrus females of both species. There was a strong relationship between rank and bout length in the pigtail females, with higher-ranking females having shorter bouts; the rate of delivery for higher-ranking females was also significantly more variable than it was for lower-ranking females. For the mangabeys, lower-ranking females had significantly higher rates of delivery than did higher-ranking ones. These findings are consistent with the hypothesis that these features of calling relate to a caller's motivational state and that higher levels of sexual motivation are required by lower-ranking females before they show proceptive behavior or mating. The possibility that female-female competition may have a significant effect on important features of calling should be considered in studies that attempt to evaluate the functional significance of these vocalizations.

Natural infection of a homozygous delta24 CCR5 red-capped mangabey with an R2b-tropic simian immunodeficiency virus.

A homozygous 24-bp deletion (Delta24) was found in the CC chemokine receptor 5 (CCR5) of 11 out of 15 red-capped mangabeys (RCMs), Cercocebus torquatus torquatus, both in Africa and in an American zoo. The CCR5 Delta24 defect encompassed eight amino acids in frame in the fourth transmembrane region. Unexpectedly, RCM-009, one of 11 homozygotes (Delta24CCR5/ Delta24CCR5), was found to be naturally infected with a divergent simian immunodeficiency virus (SIV) strain, which was not R5-tropic, but used CCR2b (R2b) as its major coreceptor. SIVrcmGab1 was the only R2b-tropic SIV among other divergent SIVs tested. Cells transfected with the Delta24 CCR5 did not support entry of R5-tropic SIVmac, SIVcpz, SIVmne, HIV-2, or HIV-1, and were also inactive in signal transduction mediated by beta-chemokines. At 86.6%, the Delta24 allelic frequency was significantly higher than that of the 32-bp deletion found in humans. The Delta24 frequency was 4.1% in 34 sooty mangabeys (SMs), a geographically isolated subspecies that was naturally infected with R5-tropic SIV. Finding identical deletions in two mangabey subspecies separated for 10,000 years or more dates the Delta24 CCR5 deletion as ancient. However, the source of the selective pressure for the high rate of CCR5 deletion in RCMs remains to be determined. The high allelic frequency of the Delta24 CCR5 in RCMs, in comparison to that of SMs, suggests that R2b-tropism may have been acquired by SIVrcm, as an adaptation to CCR5 genetic defects appeared in its host.

Facial growth in Cercocebus torquatus: an application of three-dimensional geometric morphometric techniques to the study of morphological variation.

This paper presents a study of 3-dimensional growth in the facial skeleton of the mangabey, Cercocebus torquatus. The pattern of facial cortical remodelling in this species is already well mapped from an earlier study. In this paper we consider the extent to which these remodelling maps relate to ontogenetic changes in size and shape of the face. This study is based on 31 facial landmarks taken from 49 adult and subadult faces. Our analysis draws on some of the tools of geometric morphometrics and we take this opportunity to describe our implementation of these tools for 3D data. The geometric analysis permits the known remodelling maps to be interpreted in the context of the general pattern of facial growth in this species. We are also able to examine sexual dimorphism in the face of this species and consider the extent to which males and females share similar ontogenetic allometries. Our findings indicate that the general pattern of size-related shape variation during facial growth is more or less identical for males and females up to eruption of the third permanent maxillary molar (M3). After this, ontogenetic allometries appear to diverge. The finding of a common growth allometry that is well approximated for younger specimens by a simple linear model is consistent with the earlier findings of a consistent pattern of facial remodelling up to M3 eruption. We consider the implications of these findings in terms of the potential for these approaches in the study of comparative growth in related species.