bluuebunny/crossref_metadata_2025 huggingface dataset:
Biochemical and hormonal correlates of dominance and social behavior in all‐male groups of squirrel monkeys (Saimiri sciureus)
Authors: Steklis Horst D. , Raleigh Michael J. , Kling Arthur S. , Tachiki Ken
Published: June 2005

This study examined the relationship between dominance rank and several physiological and behavioral measures in stable, captive, all‐male squirrel monkey groups. Four groups, each containing three males, were observed for 12 weeks during the breeding season. Relative dominance ranking among males in each group was based on the direction of agonistic behaviors displayed. For each subject, whole blood serotonin (WBS), plasma testosterone (T), and cortisol (C) were sampled 4 to 6 times over the course of the study. Samples were separated by 1‐ to 2‐week intervals. Each group had a stable linear dominance hierarchy. WBS had small intraanimal variance and was positively related to dominance rank. In contrast, T and C were highly variable within subjects and were unrelated to dominance rank. Among alpha males, concentrations of T and C were positively correlated, and WBS and C were negatively correlated. The effect of dominance rank on the relationship between within‐animal fluctuations in WBS, T, and C and behavior was also assessed. In dominant, but not subordinate subjects, intraanimal fluctuations in WBS correlated with agonistic behavior initiated, and fluctuations in C and T correlated with huddling. In beta and gamma males, C was related to agonism received, and in gamma males to food stealing received. Dominance status also affected endocrine response to the stress of capture but not the rate of sneezing. Sneezing was positively correlated with T concentrations irrespective of dominance rank. These results extend the association between WBS and dominance rank previously reported in Old World monkeys to a New World monkey species, support previous suggestions that mean T and C titers are not reflective of dominance rank in well‐established groups, and indicate that dominance rank affects adrenocortical response to the stress associated with capture and anesthesia.
Reproductive cycles in Tarsius bancanus
Authors: Wright Patricia C. , Izard M. Kay , Simons Elwyn L.
Published: June 2005

The reproductive condition of three pairs of Bornean tarsiers (Tarsius bancanus) was documented for 16 months. Each pair was housed separately under a constant photoperiod (L:D = 11.5:12.5) similar to that in their native habitat. Reproductive cycles of females were monitored visually for 6 months and were then monitored with vaginal smears and measurements of external genitalia for an additional 10 months. Progressive proliferation and cornification of vaginal epithelial cells during proestrus and estrus was accompanied by an enlargement of the external genitalia. Cycle lengths averaged 24.0 ± 3.2 days. The external genitalia were swollen each cycle for a period of 6–9 days. Copulations occurred on the 1st day of estrus, which lasted 1–3 days. No menstruation was observed. There was no evidence of seasonality of estrous cycles with this photoperiod. Testicular measurements of males showed no overt seasonal changes. There was variation in testicular size, and one male copulated at a range of testicular sizes. The data indicate that T. bancanus has estrous cycles similar to those of prosimian primates and some New World monkeys and that these cycles occur throughout the year under constant photoperiodic conditions.
Endocrine and behavioral correlates of drought in wild olive baboons (Papio anubis)
Authors: Sapolsky Robert M.
Published: June 2005

As part of a long‐term study in behavioral endocrinology, wild olive baboons (Papio anubis) living in the Serengeti ecosystem of East Africa have been under study since 1978. The present report documents behavioral and endocrine changes associated with the severe drought of 1984. During this time, the annual rainy season failed and grassland biomass was severely reduced in the Serengeti. Baboons were able to maintain body weight but spent significantly more time foraging for food. In four prior years of study, basal testosterone concentrations were remarkably stable in adult and subadult males. In contrast, during the drought, there was a highly significant 60% decline in basal concentrations of the steroid. This testicular suppression was apparent in males of all ranks (by approach‐avoidance criteria). Prior studies with this population, which examined the role of acute and chronic stressors in similarly suppressing testosterone concentrations, suggested that the present instance was in response to the stress of the drought. The drought was also associated with significant reductions in the rates of escalated aggression among males. However, the distribution of fights between high‐ranking males, between low‐ranking males, and between high‐ and low‐ranking males did not change from prior years, nor was the dominance hierarchy inordinately unstable during this time. These findings agree with previous evidence that indicates that suppressed testosterone concentrations in males can be associated with lower rates of aggressive behaviors but that the steroid plays a predominantly facilitative rather than activational role. Finally, rates of approach‐avoidance interactions and of male sexual behaviors were unchanged during the drought. These findings agree with an endocrine literature that indicates that reproductive behavior or physiology in primates is rarely disrupted by suppression of testosterone concentrations of the magnitude of the present case.
Social responding to mirrors in rhesus macaques (Macaca mulatta): Effects of changing mirror location
Authors: Suarez Susan D. , Gallup Gordon G.
Published: June 2005

Two rhesus macaques (Macaca mulatta) with a lifetime of continuous exposure to mirrors showed a dramatic and reliable reinstatement of social behavior directed toward the mirror when it was simply moved to a new location. These data are discussed in the context of repeated failures to find self‐recognition in monkeys and several recent claims that a cessation of social behavior directed toward mirrors can be used as evidence for the beginning of self‐recognition in nonhuman primates.
Territorial shift in the yellow‐handed titi monkey (Callicebus torquatus)
Authors: Easley Stephen Phillip , Kinzey Warren G.
Published: June 2005

In this study, the ranging pattern of a single group of monogamous and territorial Callicebus torquatus was recorded over a 7‐year period from 1974 to 1980. Data on ranging pattern were recorded by direct observation; daily movement patterns were plotted on an accurate, scaled map of the territory. Data were obtained during 1–3‐month studies each year from 1974 to 1978 and in 1980, as well as during a 12‐month study in 1979‐1980. These studies show that the exclusive territory maintained by the group was not spatially stable over the 7‐year period. The group gradually moved its territory to the northeast, to the extent that the territory used in 1980 was completely noncoincident with the territory used in 1974 by the same group. Analysis of the ranging pattern from the 12‐month study indicates that the group did not exhibit seasonal preferences for different parts of its range. Seasonal ranging patterns, therefore, are not likely to account for the observed territorial shift. It is suggested that territorial shifting may be related to the need for monogamous groups to find new territories for their offspring.
Secondary sex ratios by maternal rank, parity, and age in captive rhesus macaques (Macaca mulatta)
Authors: Small Meredith F. , Hrdy Sarah Blaffer
Published: June 2005

Analysis of 645 conceptions by captive rhesus macaques (Macaca mulatta) with known reproductive histories indicated that maternal age and parity had little effect on the sex of progeny. There was, however, a slight indication that high‐ranking females produced a higher proportion of daughters and relatively fewer sons than did low‐ranking females. These results provide only weak support for the “advantaged daughter” hypothesis suggested by three previous studies of cercopithecine monkeys, and therefore they further confound the conflicting results for macaques and baboons in general.
Uacaries, new world monkeys of the genusCacajao(Cebidae, Platyrrhini): A preliminary taxonomic review with the description of a new subspecies
Authors: Hershkovitz Philip
Published: June 2005

The two known species of uacaries, inhabitants of the upper Amazonian region, are the black headCacajao melanocephaluswith subspeciesC. m. melanocephalusHumboldt andC. m. ouakarySpix, and the larger bald head uacariC. calvuswith subspeciesC. c. ucayaliiThomas,C. c. rubicundusI. Geoffroy and Deville,C. c. calvusI. Geoffroy, andC. c. novaesidescribed as new. The diagnostic generic characters described are the external, cranial, dental, some postcranial, and cytogenetic. The species are described and compared and their geographic distribution plotted with those of their subspecies delimited. Sexual differences are outlined. Apart from size‐related characters, the species and subspecies are distinguished by pelage pattern of head and coloration in general. It is shown that both species could have diverged from a hairy‐headed melanistic ancestral form. Pelage divergence in the descendants was expressed by the more pilose head ofC. melanocephalus, and less pilose ofC. calvus. Coloration differentiation was geographic and followed metachromic lines with mutation from eumelanism to partial pheomelanism (reddish or golden) inC. melanocephalusand to virtually complete pheomelanism inC. calvus. The subspecies of each species are distinguished by color patterns resulting from selective bleaching or dilution of the pheomelanin fields. The most saturate pheomelanic subspecies ofC. calvusisC. c. ucayaliiand the most dilute is the albinoticC. c. calvus. Correlation between coloration and environment is not evident. A gazetteer identifies all locality records plotted by numbers on the geographic distribution maps.
Variability and stability in the rank relations of nonhuman primate females: Analysis by computer simulation
Authors: Hausfater Glenn , Cairns Sara J. , Levin Rachel N.
Published: June 2005

This paper summarizes results of simulation analyses aimed at elucidating the way in which two important dimensions of female rank orders—nepotism and age‐gradedness—are affected by variation in individual strategies of rank acquisition on the one hand and by variation in population‐wide demographic parameters (eg, birth rate, death rate, etc) on the other. Female rank orders in simulated primate groups were characterized by substantial variability on a year‐to‐year basis in both nepotism and age‐gradedness owing to stochastic processes alone. Although, in general, groups characterized by strongly nepotistic rank orders were not also strongly age‐graded, quantitative measures of these two rank‐order dimensions for individual groups showed little stability over intervals of time exceeding 3 years. Surprisingly, changes in birth and death rates did not strongly affect either nepotism or age‐gradedness so long as average group size remained constant. However, in populations characterized by expanding or declining group size, variation in demographic parameters did indeed exert a powerful influence on the structure of female rank orders. Both nepotism and age‐gradedness were also strongly affected, and in quite different ways, by changes in the rules of rank acquisition by females. In sum, the present analyses suggest that differences between species in the degree of nepotism and age‐gradedness characteristic of their female rank orders does not in and of itself constitute evidence that the females of those species use markedly different strategies of rank acquisition.
The socioecology of the black mangabey (Cercocebus aterrimus) near Lake Tumba, Zaire
Authors: Horn Arthur D.
Published: June 2005

Socioecological data were gathered in a two‐year study of black mangabey monkeys in a secondary forest on the west bank of Lake Tumba, Zaire. The mangabeys of the study area lived in multi‐male, multi‐female groups numbering between 14 and 19 individuals. They were completely arboreal, fed mostly on fruit and nuts, and frequently were associated with other species of arboreal monkeys. Their predators were human hunters and the crowned hawk‐eagle. The primary vocalizations of black mangabeys were analyzed and their social contexts compared with those of closely related gray‐cheeked mangabeys, to which they were found to be very similar.
Selection of secondary growth areas by vervet monkeys (Cercopithecus aethiops)
Authors: Chapman Colin A.
Published: June 2005

Habitat selection by a group of vervet monkeys (Cercopithecus aethiops) living on the savanna peninsula of St. Kitts was investigated by the intensive sampling of 12 transects. The vervets exhibited nonrandom use of habitats. Examination of 20 ecological variables in each of the habitat types revealed that the vervets preferentially used areas of secondary growth characterized by high density and diversity of tall food plants. It is suggested that the preferential use of secondary growth habitat can be attributed to the fact that these areas have high levels of plant productivity and that they have a large proportion of their productivity available for consumption.
Direct measurements of urinary estrone conjugates during the normal menstrual cycle of the gorilla (Gorilla gorilla)
Authors: Czekala N. M. , Mitchell W. R. , Lasley B. L.
Published: June 2005

A direct immunoassay for urinary estrone conjugates (estrone sulfate and estrone glucuronide) was used to assess the preovulatory estrogen rise in normal gorilla menstrual cycles. Immunoreactive estrone conjugates in samples concomitantly assessed for total estrogen immunoreactivity reflected similar profiles throughout the cycle; however, the speed and resolution of the direct assay for conjugates indicate this method to be more accurate in monitoring ovulation than the measurement of total immunoreactive estrogens. In a single conceptive ovarian cycle, urinary estrone conjugate continued to rise in the luteal phase, indicating that this test may also be useful for detecting early pregnancy. The application of this technique provides clear profile of ovarian function in gorillas as well as in other primate species.
Experimental rank reversals among peers in Macaca fuscata: Rank is maintained after the removal of kin support
Authors: Chapais Bernard , Larose Francois
Published: June 2005

In many species of cercopithecines female rank is inherited matrilineally so that maternal kin occupy adjacent ranks. A female is said to have acquired her matrilineal rank in relation to a given subordinate female when the submission she receives from that female and the aggression she directs to her are both unidirectional. Kin support appears to be important in that process (rank acquisition). Matrilineally dominant females also appear to need kin support for maintaining their rank once they have acquired it. This is inferred from observations indicating that subordinates can form kin‐based coalitions and outrank single dominant females. Therefore, if subordinates did not, or could not, form coalitions, the maintenance of rank among similar‐sized females might be independent of kin support. One test of this hypothesis would be to remove all kin support shortly after rank acquisition has taken place. We report such a test performed in a group of captive Macaca fuscata composed of three families with similar age‐sex compositions. Experimental subgroups were formed by placing together peers from different families and a single kin (ally) of one subordinate peer (mother or older sister). These experiments induced a series of rank reversals whereby the subordinate peer, whose ally was present, outranked the dominant peers. Following the rank reversals, the ally of the newly dominant peer was removed and the peers left together. All five experimentally inverted rank orders of peers remained stable. The finding that experimentally subordinate individuals abstained from challenging experimentally dominant peers despite their long ontogenetic experience of reversed dominance roles suggests (1) that matrilineal rank acquisition is a punctuate (versus ontogenetically cumulative) process, (2) that the maintenance of rank among peers does not necessitate kin support if subordinates cannot form coalitions, and (3) that the “minimal risk constraint on competition” helps account for the stability of matrilineal hierarchies.
Chromosomal evolution in Malagasy lemurs: X. chromosomal banding studies of Propithecus diadema edwardsi and Indri indri and phylogenic relationships between all the species of the Indriidae
Authors: Rumpler Y. , Warter S. , Ishak B. , Dutrillaux B.
Published: June 2005

The R‐banded karyotypes of two Indriidae, Propithecus diadema and Indri indri, are described and compared with each other and with those of the other species of this family, previously reported, Avahi laniger and Propithecus verreauxi. These comparisons show that 30 chromosomal rearrangements, including 21 Robertsonian translocations and eight pericentric inversions, differentiate these karyotypes. A phylogenic diagram is proposed, showing the early separation of Avahi and the relatively late divergence of the three other species. A populational evolution has occurred between the three other species, but Indri is clearly separated from the two other species by at least five complex rearrangements, although it shares four Robertsonian translocations with P. verreauxi but not P. diadema.
Abnormal behaviors, with a special focus on rocking, and reproductive competence in a large sample of captive chimpanzees (Pan troglodytes)
Authors: Fritz J. , Nash L. T. , Alford P. L. , Bowen J. A.
Published: June 2005

Chimpanzees (Pan troglodytes) are endangered in the wild and may no longer be imported into the United States. Of those animals presently in captivity, candidates for breeding programs must be identified to insure a self‐sustaining captive population. Some have suggested that poor reproductive performance might be linked to the performance of abnormal behaviors. In Study 1, three institutions housing breeding colonies of chimpanzees (86 males, 103 females) surveyed their animals for abnormal behaviors, copulatory performance, and, for females, maternal competence. In neither sex was there a positive association between absence of copulation and the presence of any of 18 forms of abnormal behavior. No one abnormal behavior was positively associated with inadequate maternal performance. Contrary to expectations, in both sexes (significantly for females), copulators exhibited more forms of abnormal behaviors than did noncopulators. In contrast, good mothers did show slightly fewer different forms of abnormal behaviors than did inadequate mothers. No specific combination of abnormal behaviors was associated with lack of copulatory performance in either sex or with inadequacy of maternal behavior. Significant sex differences occurred only in 2 of the 18 abnormal behaviors (coprophagy and self‐clinging), both with females showing the higher prevalence. In Study 2, the rate of rocking in 5 male and 14 female chimpanzees at the Primate Foundation of Arizona was found to be relatively high among some reproductively competent subjects. Some rocking had forms and contexts indicative of aggressive displays. We conclude that chimpanzees should not be disregarded as potential breeders or as candidates for resocialization and breeding programs solely because they exhibit abnormal behaviors. Anyone involved in assessing well‐being needs to be aware of individual differences among animals in the stimuli that may elicit rocking behavior. If they are strangers, they may elicit display rocking which does not indicate a lack of well‐being. © 1992 Wiley‐Liss, Inc.
Survey of parasites of rhesus monkeys housed in small social groups
Authors: Phillippi Kathrine M. , Clarke Margaret R.
Published: June 2005

A survey of specific parasites in fecal samples randomly collected from socially housed rhesus monkeys was done over a 1‐year period. Differences in frequency of samples with parasites, and number of different species per sample, were assessed by social group composition, social group size, female reproductive status, and season of the year. Common parasites were Entamoeba coli, Iodamoeba bütschlii, Balantidium coli, Strongyloides fülleborni, and Trichuris trichiura. Samples from juvenile/subadult groups had more species of potentially pathogenic parasites per sample but fewer species of nonpathogenic parasites per sample than samples from adult groups. When group size reached 12 to 16 animals, the number of samples with helminths doubled. Samples collected from groups with gestating/ lactating females had more species of nonpathogenic parasites than samples collected from groups with cycling or noncycling females. Fewer samples collected in the spring had helminths than samples collected during the fall, winter, and summer. The number of potentially pathogenic species present per sample was highest during the summer. Following anthelminthic treatment, the number of helminthic species present per sample and the number of samples with helminths remained low, then began increasing after 2 to 3 months. The number of potentially pathogenic species per sample decreased while animals were fed an inadvertently vitamin C deficient chow. © 1992 Wiley‐Liss, Inc.
Chimpanzee genital swelling and its role in the pattern of sociosexual behavior
Authors: Wallis Janette
Published: June 2005

Behavioral observations were made on thirteen female and seven male adult group‐living chimpanzees (Pan troglodytes). The behavioral data were analyzed as a function of the day of the females' menstrual cycles to explore the possible interrelationship between genital swelling and sociosexual behavior of female chimpanzees.

Copulatory behavior was confined almost entirely to the period of genital swelling and the occurrence of male‐to‐female genital inspection (both female‐ and male‐initiated) was negatively correlated with the days from swelling onset, i.e., as the presumed day of ovulation approached, genital inspection decreased, while copulatory behavior increased. In addition, more females groomed their male cagemates during the luteal phase than in the follicular phase of their cycles, whereas male‐to‐female grooming was positively correlated with the progress of the cycle, with peaks during the time of swelling onset and menstruation.

The profile of sociosexual behavior observed throughout the menstrual cycle suggested that, although chimpanzees exhibit an extended period of sexual receptivity and genital swelling, the presumed fertile period is not concealed. The role of genital swelling in chimpanzees is discussed in relation to the possible hormonal effect on female sexuality and the evolution of chimpanzee mating strategies. © 1992 Wiley‐Liss, Inc.
Influence of ultraviolet B radiation on vitamin D3 metabolism in vitamin D3‐resistant New World primates
Authors: Gacad Mercedes A. , Deseran Mark W. , Adams John S.
Published: June 2005

We investigated the occurrence of rickets in adolescent tamarins (Saguinus imperator) residing at the Los Angeles Zoo. Compared to tamarins in the same colony without clinical evidence of bone disease (N = 6), rachitic platyrrhines (N = 3) had a decrease in their serum calcium concentration (P < .05). The affected tamarins also had lower serum 1,25‐dihydroxyvitamin D3 (1,25‐(OH)2D3) levels than did nonaffected colony mates, but 2–10‐fold higher concentrations than in Old World primates of a comparable developmental stage. New World primates in many different genera are known to exhibit target organ resistance to the active vitamin D3 metabolite, 1,25‐(OH)2D3, compensated by maintenance of high circulating concentrations of 1,25‐(OH)2D3. The relatively low serum 1,25‐(OH)2D3 concentration in rachitic tamarins and ultraviolet B radiation deficient environment of these primates suggested that bone disease may be linked to a deficiency in substrate for 1,25‐(OH)2D3, 25 hydroxyvtamin D3 (25‐OHD3). Chronic exposure of platyrrhines in three different vitamin D resistant genera to an artificial UVB source resulted in 1) a significant increase in the mean serum 25‐OHD3 (P < .001) and 1,25‐(OH)2D3 (P < .02) level over that encountered in platyrrhines not exposed to UVB; and 2) prevention of rachitic bone disease in irradiated individuals. These data further show that the serum 25‐OHD3 and 1,25‐OH2D3 levels are positively correlated in vitamin D‐resistant platyrrhines (r = 0.64; P= .0014) and suggest that a compromise in cutaneous vitamin D3 production by means of UVB deprivation may limit necessary 1,25‐(OH)2D3 production. © 1992 Wiley‐Liss, Inc.
Location‐restricted dyadic interactions and maternal patterns
Authors: Andrews Michael W. , Rosenblum Leonard A.
Published: June 2005

The purpose of this study was to determine the impact of infant restraint on dyadic interactions and maternal foraging patterns. Five bonnet macaque (Macaca radiata) mother‐infant dyads were observed under three conditions: high foraging demand for the mothers with nonrestrained contact between mothers and infants (HFD‐NRC), high foraging demand with restrained contact (HFD‐RC), and low foraging demand with restrained contact (LFD‐RC). In the restrained contact conditions the infants lived in a nursery within the group pen that allowed dyadic nursing, contact, proximity, and grooming, but prevented the infants from being with their mothers in the remaining portions of the pen, including the foraging area. Observations began when the infants were a mean of 5.4 months old. HFD‐RC resulted in decreased dyadic contact relative to HFD‐NRC, but did not significantly affect foraging task engagement; there were, however, marked individual differences in the response patterns of the mothers. Dyadic contact was also decreased during the LFD‐RC condition, but maternal patterns under low demand resulted in lower levels of infant contact initiation. This study demonstrated the feasibility of a nursery‐restrained rearing paradigm in exploring the strategic patterns of coping with conflicting environmental and maternal demands in bonnet macaque mothers. © 1993 Wiley‐Liss, Inc.
Non‐surgical uterine flushing for the recovery of preimplantation embryos in rhesus monkeys: Lack of seasonal infertility
Authors: Seshagiri Polani B. , Bridson William E. , Dierschke Donald J. , Eisele Stephen G. , Hearn John P.
Published: June 2005

A non‐surgical uterine flushing technique was employed to recover rhesus monkey preimplantation embryos during April–‐September, a period thought to be associated with reduced fertility. A total of 22 females of proven fertility, maintained indoors under strict light and temperature control, were employed for the study in which 72 menstrual cycles were monitored. The average length of their menstrual cycle was 27.9 ± 3.8 days. The percentages of cycles that showed normal cyclic patterns of estrogen, LH, and sex‐skin color were 84.7%, 91.7%, and 90.3%, respectively. Following natural mating, uterine flushing was performed on days 4–7 of pregnancy. Of 58 attempts, 27 (46.6%) resulted in the recovery of embryonic materials. Two recoveries produced unfertilized oocytes; 20 yielded embryos which were morphologically normal, and 7 yielded damaged and/or degenerate embryos. Luteal function in cycles involving uterine flushings was evaluated by examining ovaries by laparoscopy, ovulation being confirmed in 34 of 35 examinations. Serum progesterone was > 2 ng/ml in 39 of 45 cycles. The conception rate of 46.6% noted in this study was similar (P > 0.4) to those observed from other natural matings in our colony, either during the same period (49.3%; n = 67) or during October–‐March (46.9%; n = 113). These results show that rhesus monkeys, maintained under appropriate environmental conditions, can experience normal fertile menstrual cycles throughout the summer months, and extend previous observations to demonstrate, for the first time, that preimplantation embryos can be recovered from this species year‐round. © 1993 Wiley‐Liss, Inc.
Estimation of density of gibbon groups by use of loud songs
Authors: Brockelman Warren Y. , Srikosamatara Sompoad
Published: June 2005

The density of gibbon populations may be estimated by listening for the loud duetted songs of monogamous territorial groups. This method requires a correction factor which must be estimated from the frequency of singing of an adequate number of known study groups. The correction factor and its error were estimated for pileated gibbons (Hylobates pileatus) in Khao Soi Dao Wildlife Sanctuary in southeastern Thailand. Among 30 groups studied, 47% sang per day, on average, but the variation between days and the variation in singing frequency between groups were large. Weather conditions, especially windiness, explained some variation in singing. During an area‐wide survey of groups in the sanctuary, unexplained variation in singing from day to day accounted for approximately half of the sample error of group density estimated from 1‐day listening samples. Error due to day‐to‐day variability can be reduced by listening for more than one day at each site. Correction factors based on the cumulative proportion of groups heard during longer (2–5‐day) sample periods of listening were closer to 1.0, therefore leaving less room for error and bias of the correction factor. © 1993 Wiley‐Liss, Inc.
Recognition of order effects in squirrel monkey antiphonal call sequences
Authors: Biben Maxeen
Published: June 2005

Squirrel monkeys exchange chuck vocalizations in antiphonal sequences that suggest a request for information, and a response to that request. Chucks are characterized by measurable acoustic differences, notably in peak frequency, related to their position in a sequence. To determine the cues by which animals might identify a chuck that is a request for information from one that is a response, first‐in‐sequence (α) and second‐in‐sequence (β) chucks, differing in peak frequency, were recorded from familiar individuals and strangers. These chucks, and a sham control, were played back, in the temporal context of a first‐in‐sequence call, to a target group of socially housed captive squirrel monkeys.

Animals responded more strongly to α chucks than to β chucks for calls originating from familiar individuals. No distinction was made between the α and β chucks of strangers, and all strangers' chucks got a weaker response than did familiar α chucks. Squirrel monkeys probably use acoustic differences, rather than context, to discriminate the ordinal significance of a chuck, but cannot do so unless they are familiar with the caller. © 1993 Wiley‐Liss, Inc.
Population genetics of crab‐eating macaques (Macaca fascicularis) on the island of mauritius
Authors: Kondo Mikiko , Kawamoto Yoshi , Nozawa Ken , Matsubayashi Kiyoaki , Watanabe Tsuyoshi , Griffiths Owen , Stanley Marys‐Ann
Published: June 2005

Protein polymorphisms of the crab‐eating macaque (Macaca fascicularis) on the island of Mauritius in the southwest Indian Ocean were examined electrophoretically for 201 blood samples. All of the variant types detected were those found previously in the Asian populations. Genetic variability of the island population was estimated to be Ppoly = 16% and H = 6.5%, which was lower than that of the Asian populations. A tendency that a small number of loci were highly polymorphic was observed. These results may reflect the establishment of the island population from a small number of introduced ancestors, or the existence of the bottleneck effect. For the origin of the Mauritian monkeys, comparison of electrophoretic variants suggested that they originated from the Malay Peninsula or the Greater Sunda Islands, especially from Java. Though the homozygous individuals exceeded in number as a whole, a significant subdivision was not detected in the population. © 1993 Wiley‐Liss, Inc.
Semen characteristics of the adult male chimpanzee (Pan troglodytes)
Authors: Gould Kenneth G. , Young Leona G. , Smithwick Eleanor B. , Phythyon Sarah R.
Published: June 2005

The chimpanzee, because of its similarities to the human, is especially valuable in studies of reproductive function. However, relatively little is known about the physiology of reproduction in the adult male chimpanzee. This study provides, for five adult male chimpanzees, baseline values for testicular volume without and with pressure and for cellular and biochemical characteristics of ejaculates collected by artificial vagina (AV). There was no correlation between body weight and testicular volume measured without or with pressure. The ratios of mean testicular volume without and with pressure were not statistically different among animals. Statistical analysis of penetration of denuded hamster oocytes by ejaculated chimpanzee sperm revealed no correlations between sperm count and percentage of eggs penetrated. There was significant variability in concentrations of protein and fructose and in activities of alpha‐glucosidase and acid phosphatase among samples from different animals. Computer‐assisted motion analysis (CAMA) of sperm provided baseline data on motion parameters necessary for future evaluation of this technique for semen analysis in the chimpanzee. The level of demonstrated inter‐animal variation mandates use of each animal as its own control for studies on normal and altered reproductive function. © 1993 Wiley‐Liss, Inc.
Midazolam as an effective intravenous adjuvant to prolonged ketamine sedation in young rhesus (Macaca mulatta) and Vervet (Cercopithecus aethiops sabaeus) monkeys: A preliminary report
Authors: Jacobs Bob , Harris Gregory C. , Allada Vivekanand , Chugani Harry T. , Pollack Deborah B. , Raleigh Michael J.
Published: June 2005

The present study investigated a recently developed benzodiazepine, midazolam, as an intravenous adjuvant to ketamine in infant monkeys undergoing prolonged sedation during positron emission tomography of the brain and heart. Subjects were two rhesus macaque (Macaca mulatta) and ten vervet monkeys (Cercopithecus aethiops sabaeus) ranging in age from 26 to 260 days. Midazolam was an effective intravenous adjuvant to ketamine. This treatment regime resulted in complete immobilization of the animals. Ketamine infusion rates did not vary significantly with age for either species. Sensitivity to midazolam appeared to be age‐dependent in vervets because significantly lower dose rates were sufficient to maintain anesthesia in older animals. For rhesus monkeys, midazolam dose rates decreased until approximately 4 months of age, and increased gradually thereafter. © 1993 Wiley‐Liss, Inc.
Inter‐group encounters and female transfer in mountain gorillas: Influence of group composition on male behavior
Authors: Sicotte Pascale
Published: June 2005

This paper examines the behaviors used by male gorillas (G. gorilla beringei) to influence female choice during inter‐group encounters. Encounters are related to the acquisition of females rather than to the defense of a group's range. Data on 58 independent encounters confirms that encounters are generally aggressive, but that contact aggression is less frequent than previously reported. A high number of potential migrants in one of the groups involved, rather than the newness of either group, predicts the likelihood of contact aggression between males. Encounters with a newly formed unit last longer than encounters involving established groups. Male herding serves to prevent female transfer. Females without dependent offspring are more likely than others to be herded. Proceptive females are the target of herding more often than non‐proceptive cycling females. Groups where herding has been observed are more likely to be newly formed, and they include significantly more males. This last result confirms that there are advantages to male cooperation in gorillas. It also raises the question of why such cooperation does not occur more often. © 1993 Wiley‐Liss, Inc.
Population dynamics of Macaca sylvanus in Algeria: An 8‐year study
Authors: Ménard Nelly , Vallet Dominique
Published: June 2005

The demography and dynamics of two groups, one living in an evergreen cedar‐oak forest (Tigounatine) and the other, in a deciduous oak forest (Akfadou) in Algeria, were studied from 1982 to 1990. Group size fell within the range of other wild groups except for the Tigounatine group when it reached 88 individuals before splitting into three new independent groups. The structure of the studied groups, except one which was temporarily “one male,” was comparable to that of other groups of Barbary macaques. There were 43–50% of immatures on average depending on the group. The sex ratio (M:F) of the sexually mature animals was relatively balanced (1:0.9–1.2). The mean age of primiparous females was 5.5 years in Tigounatine and 5.3 in Akfadou; the rate of reproduction of sexually mature females was 0.56 and 0.63, respectively, while the infant mortality rate was 0.23 and 0.38, respectively. Great interannual variations occurred at both sites. The differences between natality and mortality induced a higher intrinsic mean annual increase for the Tigounatine group (14.6%) than for the Akfadou group (4.8%). The rate of intergroup transfers was not correlated with the increase in group size. Integration of male immigrants did not lead to the departure of resident males. Conversely, fission process promoted a substantial increase in the number of transfers in Tigounatine.

The period presenting the greatest risk of infant mortality was the summer dry period, in both habitats. Wide interannual variations occurred in the availability of two staple foods for monkeys: caterpillars and acorns. The cumulative effects of a low acorn supply during the gestation period (autumn) and a low caterpillar supply during the beginning of the following nursing period (spring) led to a temporary increase in infant mortality. © 1993 Wiley‐Liss, Inc.
Infant survival and number of helpers in captive groups of common marmosets (Callithrix jacchus)
Authors: Rothe H. , Koenig A. , Darms K.
Published: June 2005

In a colony of captive marmoset monkeys (Callithrix jacchus), the survival rate of infants up to the age of 90 days after birth was analyzed with special reference to the number of members in the group. The number of group members (newborns excluded) varied between two (parents only) and 18 (parents plus non‐reproductive helpers); the number of adult group members varied between two and 15. Five hundred ninety‐two live‐born, parent‐reared infants of 263 litters from 56 breeding females were included in the analysis. The greatest reproductive success was observed in groups of ten to 11 members or four to five adults, including the parents. However, the survival rate was fairly constant over group size at approximately 80% of an expected maximum value and no significant correlation was observed between the total number of group members and infant survival rate, or between the number of adult members and infant survival. While helpers may be necessary to increase the survival rate of infants in wild groups, help of non‐reproductive animals is not required in captivity, where energetic demands are comparatively low and ecological constraints absent. Under laboratory conditions the parents' skill in infant handling and the mother's physical condition, i.e., the ability to provide enough milk for the infants, is likely to be the most important factor for infant survival. © 1993 Wiley‐Liss, Inc.
Genetic characterization of parental cell lines and biochemical analysis of somatic cell hybrids between mouse (RAG) cells and fibroblasts of Ateles paniscus chamek (primates, platyrrhini)
Authors: Seuánez Héctor N. , Alves Gilda , O'brien Stephen J.
Published: June 2005

Mouse (RAG) cells, (deficient in hypoxanthine‐phosphoribosyl‐transferase), and Ateles paniscus chamek primary fibroblasts were used in fusion experiments to generate somatic cell hybrids. Both parental cell lines were genetically characterized by karyological and biochemical analyses with 27 isozyme systems. These procedures were useful for monitoring primate chromosome segregation in somatic cell hybrids, for detecting chromosome rearrangements of primate chromosomes, and for identifying individual primate chromosomes.

These characterizations are necessary to distinguish between different hybrid cell lines and to generate a panel for gene mapping studies. This is achieved by selecting cell lines that segregate different sets of relatively few primate isozymes and chromosomes. Conversely, we eliminated hybrid cell lines either showing: (1) rearrangements between primate and mouse chromosomes, (2) extensive rearrangements of primate chromosomes, or (3) a large number of primate biochemical markers. © 1993 Wiley‐Liss, Inc.
Composition of the diet of chimpanzees and comparisons with that of sympatric lowland gorillas in the lopé reserve, gabon
Authors: Tutin Caroline E. G. , Fernandez Michel
Published: June 2005

Over an eight‐year period, a total of 174 food items were recorded for chimpanzees (Pan t. troglodytes) in the Lopé Reserve in central Gabon. Plant foods, principally fruit, dominated the diet but insects were eaten regularly, and predation on at least three species of mammal occurred infrequently. The diversity of the vegetative component of the diet (leaves, stems, and bark) was probably underestimated by fecal analysis. Comparison of chimpanzee diet at Lopé with that of sympatric lowland gorillas showed the majority of foods were eaten by both species (73% of chimpanzee food items and 57% of gorilla food items). The overlap of fruit species was greater (82% and 79%, respectively) than that of other food classes. Both chimpanzees and gorillas harvested the majority of their plant foods arboreally (76% and 69%, respectively). The high degree of dietary overlap suggested that ecological competition between these two closely related species might exist. Few overt signs of competition for food either between or within species were observed but when fruit was scarce, the diets of the two species showed greatest divergence. The major differences between chimpanzee and gorilla diet at Lopé were the larger quantities of vegetative foods regularly eaten by gorillas and their ability to resort to a diet dominated by vegetative foods when fruit was scarce. In these respects, chimpanzees at Lopé resembled populations of Pan troglodytes studied elsewhere while Lopé gorillas resembled mountain gorillas (Gorilla g. beringei) and bonobos (Pan paniscus) in their greater dependence on vegetative foods. © 1993 Wiley‐Liss, Inc.
Photopigments underlying color vision in ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus)
Authors: Jacobs Gerald H. , Deegan Jess F.
Published: June 2005

A recent examination of color vision in the ringtail lemur produced evidence that these prosimians could make color discriminations consistent with a diagnosis of trichromatic color vision. However, it was unclear if this behavior reflected the presence of three classes of cone or whether lemurs might be able to utilize signals from rods in conjunction with those from only two classes of cone. To resolve that issue, spectral sensitivity functions were obtained from ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus) using a noninvasive electrophysiological procedure, electroretinographic flicker photometry. Results from experiments involving chromatic adaptation indicate that these lemurs routinely have only a single class of cone photopigment in the middle to long wavelengths (peak sensitivity of about 545 nm); they also have a short‐wavelengthsensitive cone pigment with peak of about 437 nm. The earlier behavioral results are suggested to have resulted from the ability of lemurs to jointly utilize signals from rods and cones. The cone pigment complements of these lemurs differ distinctly from those seen among the anthropoids. © 1993 Wiley‐Liss, Inc.
Acoustic analysis of wild chimpanzee pant hoots: Do Kibale Forest chimpanzees have an acoustically distinct food arrival pant hoot?
Authors: Clark Adam P. , Wrangham Richard W.
Published: June 2005

Recordings were made of 193 pant hoots given by 6 adult males during ad lib sampling over a 16‐month period in 1988 and 1989. The presence or absence of a let‐down phase, and acoustic measures of the let‐down and climax phases of the calls, were compared for different call contexts to determine if an acoustically distinct pant hoot was given uniquely upon arrival at fruiting trees. The greatest proportion of pant hoots with a let‐down (LD pant hoots) occurred immediately upon arrival at fruiting trees. However, LD pant hoots also occurred at other times during feeding bouts. The frequency and duration of the first exhaled element of 19 letdown phases were measured, and four measures were made on the highest pitched element of 49 climax phases: duration, maximum and minimum frequencies, and average frequency. No differences were found in these acoustic measures that distinguished calls given immediately upon arrival at a food tree from calls given later during feeding bouts. Thus no evidence was found that an acoustically distinct pant hoot was given uniquely upon arrival at fruiting trees. However, the analyses did suggest that identifiable pant hoot variants are given in different social contexts. The proportion of LD pant hoots decreased in more interactive social contexts, and other acoustic features may be available to distinguish this pant hoot variant at long distances. We suggest that different pant hoot variants might broadcast information specific to social, as opposed to ecological, context. © 1993 Wiley‐Liss, Inc.
Rank differences in the production of vocalizations by wild chimpanzees as a function of social context
Authors: Clark Adam P.
Published: June 2005

Rank differences in the production of vocalizations by wild, semihabituated, unprovisioned chimpanzees were investigated during a 10‐month study in the Kibale Forest, Uganda. Vocalization rates were calculated from data collected during 230 hours of focal‐animal sampling on adult females, adult males, and subadult males. Rates were calculated according to whether individuals were alone, with adult females only, or in mixed parties, and the results were compared with published data collected at the Gombe provisioning area. Adult females and low‐ranking adult and sub‐adult males were generally quiet except when they were in mixed parties, whereas high‐ranking males vocalized in all social contexts. These results were in partial contrast to data collected at Gombe, which indicated that vocal production was similar across all age and sex classes. Vocal production at Gombe did, however, resemble that from mixed parties at Kibale, suggesting that the provisioning area at Gombe was comparable to a natural socioecological context occurring at large fruiting trees. It is suggested that low‐ranking chimpanzees refrain from loud vocalizing when they are alone or with females only in order to avoid attracting feeding competition and/or potentially aggressive males. These individuals may vocalize when they are associating with high‐ranking males in order to advertise the presence of large parties and to deter other individuals from joining them. The use of loud, interparty calls by high‐ranking males, when alone or with others, is consistent with the greater sociality of adult male chimpanzees. Loud calling might be advantageous for adult males in attracting mates or allies. © 1993 Wiley‐Liss, Inc.
Field Techniques for Monitoring Cotton‐Top Tamarins (Saguinus oedipus oedipus) in Colombia
Authors: Savage Anne , Giraldo L. Humberto , Sblumer Evan , Soto Luis H. , Burger William , Snowdon Charles T.
Published: June 2005

We present reliable field techniques for capturing, anesthetizing, and Iidentifying individual cotton‐top tamarins (Saguinus oedipus oedipus). A new technique is presented for radio‐tracking small bodied primates. A backpack‐style harness was designed to carry a transmitter. This system appears effective in minimizing potential injury and does not appear to interfere with the normal behavior of the animal. © 1993 Wiley‐Liss, Inc.