| solving a cooperation task without taking into account the partner's behavior: the case of capuchin monkeys (cebus apella). | four pairs of tufted capuchin monkeys (cebus apella) were tested in a task requiring that both partners pull a handle simultaneously in order for both to be rewarded. the experimental design, an improved version of that of r. chalmeau, e. visalberghi, and a. gallo (1997), aimed at assessing the extent to which a monkey that is pulling takes account of the behavior and spatial position of its partner, that is, whether the monkey understands what cooperation involves. although all pairs succeeded, ... | 2000 | 10994846 |
| scanning electron microscopy study of the choroid plexus in the monkey (cebus apella apella). | the cells of the choroid plexus of the lateral ventricles of the monkey cebus apella apella were examined through scanning electron microscopy at contributing to the description of such structures in primates. the animals were anesthetized previously with 3% hypnol intraperitoneally and after perfusion with 2.5% glutaraldehyde, samples of the choroid plexus were collected after exhibition of the central portion and inferior horn of the lateral ventricles. the ventricular surface of those cells p ... | 2000 | 11018817 |
| histopathological characterization of nephritides in the brown capuchin monkey, cebus apella (primates: cebidae). | the renal lesions are of special importance in the captive primates. the most commonly pathologies are: pyelonephritis, nephrocalcinosis, glomerulonephritis, congenital malformations, hydronephrosis and functional diseases. we report the histopathological study of renal lesions of five cases of deaths in cebus apella (primates) of the argentinean primate center. the ages of the monkeys were from 4 months to 15 years old. microscopically, we have observed principally acute diffuse proliferative g ... | 2000 | 11021316 |
| capuchins do cooperate: the advantage of an intuitive task. | we used a cooperative pulling task to examine proximate aspects of cooperation in captive brown capuchin monkeys, cebus apella. specifically, our goal was to determine whether capuchins can learn the contingency between their partner's participation in a task and its successful completion. we examined whether the monkeys visually monitored their partners and adjusted pulling behaviour according to their partner's presence. results on five same-sex pairs of adults indicate that (1) elimination of ... | 2000 | 11032655 |
| fishing with a bait: a note on behavioural flexibility in cebus apella. | | 2000 | 11093040 |
| manual laterality in haptic and visual reaching tasks by tufted capuchin monkeys (cebus apella). an association between hand preference and hand accuracy for food discrimination. | manual laterality was examined in 26 tufted capuchins (cebus apella) in three tasks differing in their sensorimotor demands and the availability of visual cues. the haptic discrimination task required the monkeys to discriminate haptically between two pumpkin seeds and two tinfoil items stuck into a tray inside an opaque box. the other two tasks required the monkeys to reach for two pumpkin seeds stuck into the tray within a transparent box with vision (visually guided reaching task) or without ... | 2000 | 11099726 |
| impact of lactation upon fertility in the new world primate capuchin monkey (cebus apella). | in the present paper, we have studied the impact of lactation upon fertility in the capuchin monkey, cebus apella, under laboratory conditions. nursing females (ten females, 12 postpartum periods) presented lactational amenorrhea (first menses at 159.2 +/- 9.0 vs 42.6 +/- 5.8 days postpartum in five non-nursing females, seven postpartum periods). plasma estradiol and progesterone concentrations during lactational amenorrhea were lower than those during the follicular phase of the menstrual cycle ... | 2000 | 11168826 |
| failure to induce tumors in the large intestine of capuchin mokeys (cebus apella) by using 1,2-dimethylhydrazine. | the purpose of this study was to produce tumors in the large intestine of capuchin monkeys (cebus apella) by the administration of the colonotropic carcinogen 1,2-dimethylhydrazine (dmh). the subjects were 12 monkeys, all males, age 30 months, with a mean weight of 2.858 kg. the dmh was administered subcutaneously to six of the monkeys at a dosage of 25 mg/kg of body weight once a week for 16 weeks; control monkeys received an equivalent volume of the stock solution without dmh. twenty months af ... | 2000 | 11168827 |
| phencyclidine (pcp)-induced deficits of prepulse inhibition in monkeys. | prepulse inhibition (ppi) of the acoustic startle reflex is a measure of sensorimotor gating which occurs in both rodents and humans. ppi is deficient in severe neuropsychiatric disorders such as schizophrenia. we investigated ppi in 10 adult monkeys (cebus apella). stimuli were 115 db white noise startle pulses, either alone or preceded by 120 ms with a prepulse of either 8 or 16 db above the 70 db background noise. experiments included a pretreatment baseline session and a session following tr ... | 2001 | 11201070 |
| conservation of absolute foveal area in new world monkeys. a constraint on eye size and conformation. | the foveal specializations of five new world monkeys, the marmoset, callithrix jacchus; the golden-handed tamarin, saguinus midas niger; the squirrel monkey, saimiri ustius; the capuchin monkey, cebus apella; and the howler monkey, alouatta caraya were compared. although retinal area varies by over a factor of two in these monkeys, the area of the fovea does not covary with retinal area and remains approximately the same absolute size, as measured by the dimensions of the high density region of ... | 2000 | 11251320 |
| increased incidence of dyskinesias and other behavioral effects of re-exposure to neuroleptic treatment in social colonies of cebus apella monkeys. | typical neuroleptic medications are still administered to as many as 40% of patients receiving antipsychotic treatment in the us. intermittent administration or interruption of long-term neuroleptic medication for schizophrenia may increase the incidence of human tardive dyskinesias, and similarly may produce increasingly marked motor side-effects, parkinsonism, and other behavioral pathologies in non-human primates. | 2001 | 11271400 |
| muc1 and glycan expression in the oviduct and endometrium of a new world monkey, cebus apella. | cebus apella is a new world monkey that has a menstrual cycle of 18-23 days with implantation at approximately luteal day 5. the aim of this study was to characterize by lectin- and antibody-labeling the distribution of muc1 and associated glycans on the endometrial and oviductal epithelium during the luteal phase of the cycle. endometrial histology showed a thin endometrium, with glands extending deeply into the myometrium. no obvious evidence of secretory differentiation in cells of either the ... | 2001 | 11319162 |
| connections of the medial posterior parietal cortex (area 7m) in the monkey. | the afferent and efferent cortical and subcortical connections of the medial posterior parietal cortex (area 7m) were studied in cebus (cebus apella) and macaque (macaca fascicularis) monkeys using the retrograde and anterograde capabilities of the horseradish peroxidase (hrp) technique. the principal intraparietal corticocortical connections of area 7m in both cebus and macaque cases were with the ipsilateral medial bank of the intraparietal sulcus (mip) and adjacent superior parietal lobule (a ... | 2001 | 11360237 |
| meiosis and chromosome painting of sex chromosome systems in ceboidea. | the identity of the chromosomes involved in the multiple sex system of alouatta caraya (aca) and the possible distribution of this system among other ceboidea were investigated by chromosome painting of mitotic cells from five species and by analysis of meiosis at pachytene in two species. the identity of the autosome #7 (x2) involved in the multiple system of aca and its breakage points were demonstrated by both meiosis and chromosome painting. these features are identical to those described by ... | 2001 | 11376445 |
| abundance, diversity, and patterns of distribution of primates on the tapiche river in amazonian peru. | this work presents data on the relative diversity, abundance, and distribution patterns of primates in a 20 km2 area of the tapiche river in the peruvian amazon. population data were collected while the study area was both inundated and dry (march to september 1997) using conventional line-transect census techniques. survey results reflected the presence of 11 primate species, but population parameters on only eight of the species will be presented, including saddleback tamarins (saguinus fuscic ... | 2001 | 11376449 |
| cebus apella (primata: cebidae) as a new host for fonsecalges johnjadini (acari: psoroptidae, cebalginae) with a description of anatomopathological aspects. | mites collected from the auditory canal of cebus apella (capuchin monkey), family cebidae, were identified as fonsecalges johnjadini (psoroptidae, cebalginae). it is the first record of this parasite from this monkey. this paper emphasizes the importance of clinical and anatomopathological examinations for parasitic diagnosis in wild animals. | 2001 | 11391419 |
| visual responses of ganglion cells of a new-world primate, the capuchin monkey, cebus apella. | 1. the genetic basis of colour vision in new-world primates differs from that in humans and other old-world primates. most new-world primate species show a polymorphism; all males are dichromats and most females trichromats. 2. in the retina of old-world primates such as the macaque, the physiological correlates of trichromacy are well established. comparison of the retinae in new- and old-world species may help constrain hypotheses as to the evolution of colour vision and the pathways associate ... | 2000 | 11432364 |
| the inferior parietal lobule is the target of output from the superior colliculus, hippocampus, and cerebellum. | the inferior parietal lobule (ipl) is a functionally and anatomically heterogeneous region that is concerned with multiple aspects of sensory processing and sensorimotor integration. although considerable information is available about the corticocortical connections to the ipl, much less is known about the origin and importance of subcortical inputs to this cortical region. to examine this issue, we used retrograde transneuronal transport of the mcintyre-b strain of herpes simplex virus type 1 ... | 2001 | 11487651 |
| representation of serial order in humans: a comparison to the findings with monkeys (cebus apella). | in a number of studies, serially organized behavior in humans has been examined using a procedure developed for use with pigeons and monkeys. there have been few direct comparisons, however, between the data collected with humans and that collected with nonhumans, and none with respect to the interesting latency effects noted with nonhumans. the purpose of this experiment was to make this comparison. human subjects were trained to respond to five simultaneously presented stimuli (a, b, c, d, and ... | 2001 | 11495113 |
| distribution of calbindin, parvalbumin and calretinin in the lateral geniculate nucleus and superior colliculus in cebus apella monkeys. | we studied the distribution of the calcium-binding proteins calbindin, parvalbumin and calretinin, in the superior colliculus and in the lateral geniculate nucleus of cebus apella, a diurnal new world monkey. in the superior colliculus, these calcium-binding proteins show different distribution patterns throughout the layers. after reaction for calretinin one observes a heavy staining of the neuropil with few labeled cells in superficial layers, a greater number of large and medium-sized cells i ... | 2001 | 11522436 |
| tissue printing of astroglial interlaminar processes from human and non-human primate cerebral cortex. | astroglial interlaminar processes are unique features of the cerebral cortex of adult primates, including man. the functional role of these processes in the primate cerebral cortex is largely unknown. the development and standardization of procedures that could maximize the utilization of primate brain samples is required for the experimental analysis of the individual and collective dynamic properties of interlaminar glial processes. with this aim and in order to assess the relative stability o ... | 2001 | 11543958 |
| effects of phencyclidine on prepulse inhibition of acoustic startle response in the macaque. | prepulse inhibition (ppi) of the acoustic startle response (asr) provides an index of neurophysiological dysfunction in schizophrenia and a method for analyzing underlying neurochemical mechanisms. in rodents, phencyclidine (pcp) and other n-methyl-d-aspartate receptor (nmdar) antagonists induce schizophrenia-like ppi deficits. similar effects have recently been observed in a new world monkey species, cebus apella. | 2001 | 11549218 |
| overlap of saccadic and pursuit eye movement systems in the brain stem reticular formation. | recent physiological studies have suggested that there are several sites of interaction between the neural pathways that control saccadic eye movements and those that control visual pursuit movements. to address the question of saccade/pursuit interaction from a neuroanatomical point of view, we have studied the connections from the smooth and saccadic eye movement subregions of the frontal eye field (fefsem and fefsac, respectively) to the rostral interstitial nucleus of the medial longitudinal ... | 2001 | 11731560 |
| morphology of horizontal cells in the retina of the capuchin monkey, cebus apella: how many horizontal cell classes are found in dichromatic primates? | the morphology of horizontal cells was studied in the retina of dichromatic capuchin monkeys, cebus apella. the cells were labeled with the carbocyanine dye, 1,1',dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (dii), and the labeling was then photoconverted to a stable product by using a diaminobenzidine reaction. the sizes of cell body, dendritic field, and axon terminal, as well as the number of dendritic clusters and cone convergence, were measured at increasing distance from t ... | 2002 | 11793350 |
| color vision perception in the capuchin monkey (cebus apella): a re-evaluation of procedures using munsell papers. | in previous experiments based on color vision discrimination of munsell chips, pessoa et al. (behav brain res 1997;89:285-8) presented evidence of trichromatic color vision in capuchin monkeys. however, the possibility of subjects using brightness cues was not eliminated. the purpose of the present study was to reassess the color perception in cebus apella in a similar behavioral paradigm, but using a range of brightness values at each tested hue. we now report that male capuchins show a dichrom ... | 2002 | 11809506 |
| the nucleotide sequences of the parathyroid gene in primates (suborder anthropoidea). | nucleotide sequences of the parathyroid (pth) gene of 12 species of primates belonging to suborder anthropoidea were examined. the pth gene contains one intron that separates two exons that code the sequence of prepro and pth, respectively. the intron of the pth gene in cebus apella, callithrix jacchus, and saguinus oedipus was 102 bp long, whereas a 103-bp intron was observed in the remaining species. phylogenetic analysis using the nucleotide sequences of pth revealed that these 12 species of ... | 2002 | 11825036 |
| behavioral and morphological comparison of two nonhuman primate models of huntington's disease. | huntington's disease is a progressive neurodegenerative disease characterized by movement disorder, cognitive deterioration, and selective striatal degeneration. no effective treatment exists, and thus stable primate models could aid in the development of novel therapies. | 2002 | 11844244 |
| working memory in capuchin monkeys (cebus apella). | it has been suggested that delayed (non-) matching to sample (dnmts/dmts) tasks using trial-unique stimuli and short, as well as longer delay intervals, can provide important insights into animal cognition. therefore, this research examined the capability of the new world capuchin monkey (cebus apella) in perform trial-unique dmts and dnmts tasks across delay intervals ranging between 8 s and 10 min. subjects were tested using a version of the wisconsin general test apparatus mounted in front of ... | 2002 | 11844580 |
| perinatal neuroendocrine regulation. development of the circadian time-keeping system. | during gestation, the perinatal neuroendocrine axis keeps clock time. in primates, the suprachiasmatic nucleus (biological clock in mammals), shows oscillatory function by midgestation. there is evidence in rodents that the mother, during pregnancy, entrains the fetal suprachiasmatic nucleus (scn) and newborn circadian rhythms. we are investigating the role of maternal melatonin as an entraining signal for the newborn circadian time-keeping system in the cebus apella (new world non-human primate ... | 2002 | 11900892 |
| hbed ligand: preclinical studies of a potential alternative to deferoxamine for treatment of chronic iron overload and acute iron poisoning. | we have continued the preclinical evaluation of the efficacy and safety of the hexadentate phenolic aminocarboxylate iron chelator n, n'-bis(2-hydroxybenzyl) ethylenediamine-n, n'-diacetic acid monosodium salt (nahbed) for the treatment of both chronic transfusional iron overload and acute iron poisoning. we examined the effect of route of administration by giving equimolar amounts of nahbed and deferoxamine (dfo) to cebus apella monkeys as either a subcutaneous (sc) bolus or a 20-minute intrave ... | 2002 | 11929795 |
| an index of relationship quality based on attachment theory. | two measures are reported of the nature or quality of a mother-offspring (mo) relationship during development using brown capuchin monkeys (cebus apella) as models. one is a qualitative classification of mo relationships as secure, resistant, or avoidant attachments. the other is an empirical ratio of relative affiliation to agonism called the mo relationship quality, or morq, index. the two methods tapped similar relationship features so relationships high or low of a median split of morq value ... | 2002 | 11930937 |
| do tufted capuchin monkeys (cebus apella) spontaneously deceive opponents? a preliminary analysis of an experimental food-competition contest between monkeys. | a new laboratory procedure which allows the study of deceptive behavior in nonhuman primates is described. pairs of tufted capuchin monkeys faced each other in a food-competition contest. two feeder boxes were placed between the monkeys. a piece of food was placed in one of the boxes. the subordinate individual was able to see the food and to open the box to obtain the bait. a dominant male was unable to see the food or to open the box but was able to take the food once the box was opened by the ... | 2002 | 11957398 |
| understanding of the relationship between seeing and knowing by tufted capuchin monkeys (cebus apella). | the ability of four tufted capuchin monkeys (cebus apella) to recognize the causal connection between seeing and knowing was investigated. the subjects were trained to follow a suggestion about the location of hidden food provided by a trainer who knew where the food was (the knower) in preference to a trainer who did not (the guesser). the experimenter baited one of three opaque containers behind a cardboard screen so that the subjects could not see which of the containers hid the reward. in ex ... | 2002 | 11957401 |
| individual and seasonal variation in fecal testosterone and cortisol levels of wild male tufted capuchin monkeys, cebus apella nigritus. | this study tested the "challenge hypothesis" and rank-based predictions for temporal steroid production in male tufted capuchin monkeys, cebus apella. fecal samples (n = 209) collected from six wild males were analyzed for testosterone and cortisol concentration by enzyme immunoassay. the temporal pattern in male steroid production was compared to female sexual activity and rates of male aggression. the top-ranking adult male did not differ from other adult males in testosterone or cortisol conc ... | 2002 | 11971661 |
| haematology and blood chemistry of cebus apella in relation to sex and age. | an effective health care program entails the prevention, diagnosis and treatment of medical problems. a knowledge of baseline values in clinically normal individuals is essential for determining the limits between good health and disease and for understanding the changes produced by pathogenic agents. however, very little information is currently available concerning the blood chemistry and haematological values of different species of monkeys, particularly new-world primates. the values of some ... | 2001 | 11990530 |
| measurement of arsenic bioavailability in soil using a primate model. | several studies have shown limited absorption of arsenic from soils. this has led to increased interest in including measurements of arsenic relative bioavailability from soils in the calculation of risks to human health posed by arsenic-contaminated sites. most of the information in the literature regarding arsenic bioavailability from soils comes from studies of mining and smelter sites in the western united states. it is unclear whether these observations are relevant to other types of arseni ... | 2002 | 12011490 |
| fluoro jade stains early and reactive astroglia in the primate cerebral cortex. | the fluorescent agent fluoro jade was applied to cortical brain sections obtained from human patients at early postnatal ages and in patients with alzheimer's disease, and from a cebus apella monkey after mechanical lesioning of the cerebral cortex. fluoro jade labeled reactive astrocytes and early differentiating astroglial cells. | 2002 | 12133916 |
| housing and care of monkeys and apes in laboratories: adaptations allowing essential species-specific behaviour. | during the last two decades an increasing amount of attention has been paid to the housing and care of monkeys and apes in laboratories, as has been done with the housing and care of other categories of captive animals. the purpose of this review is to develop recommendations for adaptations of housing and care from our knowledge of the daily behavioural activity of monkeys and apes in natural conditions and in enriched laboratory conditions. this review deals mainly with adaptations of daily ho ... | 2002 | 12144737 |
| basal-ganglia 'projections' to the prefrontal cortex of the primate. | we used retrograde transneuronal transport of the mcintyre-b strain of herpes simplex virus type 1 to examine the extent and organization of basal-ganglia-thalamocortical projections to five regions of prefrontal cortex in the cebus monkey (cebus apella): medial and lateral area 9 (9m and 9l), dorsal and ventral area 46 (46d and 46v) and lateral area 12 (12l). all of these prefrontal areas were found to be targets of basal-ganglia output that originated in the internal segment of the globus pall ... | 2002 | 12183392 |
| abo blood groups in the primate species of cebidae from the amazon region. | the abo blood groups were determined in blood and saliva collected from 40 aotus infulatus, 74 saimiri sciureus, and 96 cebus apella from the amazonian region along the tocantins river. saliva samples were tested for human abh antigens by a standard hemagglutination inhibition test. aotus infulatus showed monomorphism, exhibiting only the b blood group. saimiri sciureus exhibited the a (67) and ab (7) phenotypes. all four phenotypes have been found in c. apella: o (8), a (52), b (19) and ab (17) ... | 2002 | 12190854 |
| histoenzymology and morphometry of the masticatory muscles of tufted capuchin monkey (cebus apella linnaeus, 1758). | samples of the anterior and posterior regions of the masseter and temporal muscles and of the anterior belly of the digastric muscle of 4 adult male tufted capuchin monkeys (cebus apella) were removed and stained with he and submitted to the m-atpase reaction (with alkaline and acid preincubation) and to the nadh-tr and sdh reactions. the results of the histoenzymologic reactions were similar, except for acid reversal which did not occur in fibers of the fast glycolytic (fg) type in the mandibul ... | 2002 | 12199536 |
| two-dimensional map of direction selectivity in cortical visual area mt of cebus monkey. | we studied the spatial organization of direction of motion in visual area mt of the cebus apella monkey. we used arrays of 6 (700 micro m apart) parallel electrodes in penetrations tangential to the cortical layers to record multi-unit responses to moving bars, at 200 micro m steps. we determined the direction selectivity at each recording site. the data from single penetrations showed cyclic and gradual changes in the direction selectivity of clusters of cells, intermixed with abrupt 180 degree ... | 2002 | 12378314 |
| structure, molecular evolution, and gene expression of primate superoxide dismutases. | mn- and cu,zn-superoxide dismutase (sod) cdnas of eight primate species, pan troglodytes, pongo pygmaeus, hylobates lar, macaca fuscata, macaca fascicularis, macaca mulatta, cebus apella, and callithrix jacchus, were cloned. the whole protein-coding sequences were covered, comparing 198 and 153 (or 154) amino acids, for mn- and cu,zn-sods, respectively. residues forming metal ligands were completely conserved in the two primate sods and nucleotide/amino acid substitutions were more frequent in c ... | 2002 | 12383507 |
| capuchin cognitive ecology: cooperation based on projected returns. | stable cooperation requires that each party's pay-offs exceed those available through individual action. the present experimental study on brown capuchin monkeys (cebus apella) investigated if decisions about cooperation are (a) guided by the amount of competition expected to follow the cooperation, and (b) made instantaneously or only after a period of familiarization. pairs of adult monkeys were presented with a mutualistic cooperative task with variable opportunities for resource monopolizati ... | 2003 | 12459220 |
| leishmania (leishmania) amazonensis-induced cutaneous leishmaniasis in the primate cebus apella: a model for vaccine trials. | a primate model of leishmaniasis was developed with the objective of future vaccine testing. lesion development and immunological parameters were studied upon primary and secondary infections. seven cebus apella were injected subcutaneously with 2 x 10(6) leishmania (leishmania) amazonensis promastigotes. erythematous nodules appeared 19-29 days p.i., which disappeared 100 days p.i. four months later, six of the monkeys were challenged with the same inoculum; three of them developed erythematous ... | 2002 | 12464422 |
| the adenosine a2a receptor agonist cgs 21680 exhibits antipsychotic-like activity in cebus apella monkeys. | the adenosine a2a receptor agonist cgs 21680 has shown effects similar to dopamine antagonists in behavioural assays in rats predictive for antipsychotic activity, without induction of extrapyramidal side-effects (eps). in the present study, we examined whether this functional dopamine antagonism and lack of eps in rodents could also be observed in non-human primates. we investigated the effects of cgs 21680 on behaviours induced by d-amphetamine and (-)-apomorphine in eps-sensitized cebus apell ... | 2002 | 12478214 |
| ontogenetic dissociation between habit learning and recognition memory in capuchin monkeys (cebus apella). | the performance of young and adult capuchin monkeys (cebus apella) on a concurrent discrimination learning (cdl) test and a delayed non-matching to sample (dnms) task were investigated. results indicate that all subjects were able to learn the cdl test with 20-pairs simultaneously and retain this stimulus/reward association within 24-h interval. in contrast, young subjects did not perform the dnms task with the same proficiency as adults. while adults' scores were above chance across all memory ... | 2003 | 12482675 |
| ticks (acari: ixodidae) on wild animals from the porto-primavera hydroelectric power station area, brazil. | from june 2000 to june 2001, a total of 741 ticks were collected from 51 free-living wild animals captured at the porto-primavera hydroelectric power station area, located alongside an approximately 180 km course of the paran river, between the states of s o paulo and mato grosso do sul, comprising 9 species of 3 genera: ambly-omma (7 species), boophilus (1) and anocentor (1). a total of 421 immature amblyomma ticks were reared in laboratory until the adult stage, allowing identification of the ... | 2003 | 12563479 |
| effect of practice on hand preference on a color visual discrimination task by capuchin monkeys (cebus apella). | effects of practice on hand preference in nonhuman primates have indicated an initial right-hemispheric advantage in new tasks that can be reversed or disappear after a long period of training. the aim of this study was to examine the effects of 6-mo. practice on hand preference in capuchin monkeys (cebus apella) performing a color visual discrimination task which requires attention and learning or memory processes. for this purpose, an early period of practice (first 200 trials) was compared wi ... | 2002 | 12578243 |
| seasonal variation in the testicular volume of capuchin monkeys (cebus apella) in captivity. | the study of the reproductive strategy developed by different species in order to adapt to their environmental conditions and their meaning in an evolutionary perspective is essential for understanding the mechanisms involved in the process of reproduction. non-human primates are very interesting models for this purpose. some species show a typical seasonal reproductive pattern, such as rhesus macaques (macaca mulatta) [sade, 1964; conaway and sade, 1965] and ring-tailed lemurs (lemur catta) [zu ... | 2003 | 12606852 |
| frontal sinus obliteration with heterogeneous corticocancellous bone versus spontaneous osteoneogenesis in monkeys (cebus apella): histologic analysis. | in this study, we evaluated the results of spontaneous osteoneogenesis of the frontal sinus with autogenous bone plug versus obliteration with heterogeneous (human) bone in monkeys (cebus apella). | 2003 | 12619000 |
| the muscarinic m1/m4 receptor agonist xanomeline exhibits antipsychotic-like activity in cebus apella monkeys. | xanomeline is a muscarinic m(1)/m(4) preferring receptor agonist with little or no affinity for dopamine receptors. the compound reduces psychotic-like symptoms in patients with alzheimer's disease and exhibits an antipsychotic-like profile in rodents without inducing extrapyramidal side effects (eps) at therapeutically relevant doses. in the present study, we examined whether the xanomeline-induced functional dopamine antagonism found in rodent studies could also be observed in nonhuman primate ... | 2003 | 12700711 |
| global and local processing of hierarchical visual stimuli in tufted capuchin monkeys (cebus apella). | capuchin monkeys' (cebas apella) relative accuracy in the processing of the global shape or the local features of hierarchical visual stimuli was assessed. three experiments are presented featuring manipulations of the arrangement and the density of the local elements of the stimuli. the results showed a clear advantage for local level processing in this species, which is robust under manipulations of the density of the local elements of the stimuli. by contrast the density of the component elem ... | 2003 | 12735359 |
| the mother-offspring relationship as a template in social development: reconciliation in captive brown capuchins (cebus apella). | mother-offspring (mo) relationship quality was investigated to determine its influence on the development of reconciliation--affiliation between opponents shortly after a fight--because it influenceswhat distressed youngsters learn about calming down. data were longitudinal and cross-sectional observational samples of 38 mo pairs of monkeys across 24 months. an mo relationship quality index (rqi) classified each pair as secure or insecure. reconciliation emerged in infancy. secure youngsters had ... | 2003 | 12735370 |
| electrophysiological imaging of functional architecture in the cortical middle temporal visual area of cebus apella monkey. | we studied the spatial organization of directionally selective neurons in the cortical middle temporal visual area (area mt) of the cebus monkey. we recorded neuronal activity from multielectrode arrays as they were stepped through area mt. the set of recording sites in each array penetration described a plane parallel to the cortical layers. at each recording site, we determined the preferred direction of motion. responses recorded at successive locations from the same electrode in the array re ... | 2003 | 12736358 |
| cebus apella, a nonhuman primate highly susceptible to neuroleptic side effects, carries the gly9 dopamine receptor d3 associated with tardive dyskinesia in humans. | tardive dyskinesia (td) is a severe side effect of traditional neuroleptics affecting a considerable number of schizophrenic patients. accumulating evidence suggests the existence of a genetic disposition to td and other extra pyramidal symptoms (eps) most strongly linked to a ser/gly polymorphism in position 9 of the d3 dopamine receptor gene (drd3). the cebus apella monkey is the favored animal model to study td and other eps because of its high susceptibility to side effects of neuroleptics. ... | 2003 | 12746734 |
| plasmid profile in oral fusobacterium nucleatum from humans and cebus apella monkeys. | fusobacterium nucleatum is a strict anaerobe and is indigenous of the human oral cavity. this organism is commonly recovered from different monomicrobial and mixed infections in humans and animals. in this study, the plasmid profile, the plasmid stability and the penicillin-resistance association in oral f. nucleatum isolated from periodontal patients, healthy subjects and cebus apella monkeys were evaluated. forty-five f. nucleatum strains from patients, 38 from healthy subjects and seven from ... | 2003 | 12751315 |
| concurrent disjoint and reciprocal classification by cebus apella in seriation tasks: evidence for hierarchical organization. | we report the results of a 4-year-long study of capuchin monkeys ( cebus apella ) on concurrent three-way classification and linear size seriation tasks using explicit ordering procedures, requiring subjects to select icons displayed on touch screens rather than manipulate and sort actual objects into groups. the results indicate that c. apella is competent to classify nine items concurrently, first into three disjoint classes where class exemplars are identical to one another, then into three r ... | 2003 | 12761655 |
| inactivated suckling mouse brain rabies vaccine provides short-term immunity in capuchin monkeys (cebus apella). | eight capuchin monkeys (cebus apella) were vaccinated against rabies with an inactivated suckling mouse brain vaccine (smbv). three 1-ml doses of 2% brain tissue suspension were given by i.m. injection at 0, 30, and 60 days. blood samples were collected at 0, 30, 60, 90, 150, 210, 240, 300, and 365 days and were tested by simplified fluorescence inhibition to titer-neutralizing antibodies. all of the animals developed neutralizing antibodies with titers >0.5 iu/ml after vaccination, but the immu ... | 2001 | 12790394 |
| exposure of hooded capuchin monkeys (cebus apella cay) to a rabid bat at a zoological park. | on 27 may 1999, a big brown bat (eptesicus fuscus) was discovered on an island exhibit at the denver zoo that contained a troop of 15 hooded capuchin monkeys (cebus apella cay). the monkeys were attacking the bat when it was discovered. the bat was collected and humanely euthanatized without direct handling and submitted to the colorado department of public health and environment virology laboratory for rabies evaluation. the monkeys had not been vaccinated against rabies virus. the next day, th ... | 2001 | 12790408 |
| urocortin in the central nervous system of a primate (cebus apella): sequencing, immunohistochemical, and hybridization histochemical characterization. | the urocortin (ucn)-like immunoreactivity and ucn mrna distribution in various regions of the nonprimate mammalian brain have been reported. however, the edinger-westphal nucleus (ew) appears to be the only brain site where ucn expression is conserved across species. although ucn peptides are present throughout vertebrate phylogeny, the functional roles of both ucn and ew remain poorly understood. therefore, a study focused on ucn system organization in the primate brain is warranted. by using i ... | 2003 | 12815753 |
| reversal of phencyclidine-induced prepulse inhibition deficits by clozapine in monkeys. | prepulse inhibition (ppi) of the acoustic startle reflex is a measure of sensorimotor gating, which occurs across species and is deficient in severe neuropsychiatric disorders such as schizophrenia. in monkeys, as in rodents, phencyclidine (pcp) induces schizophrenia-like deficits in ppi. in rodents, in general, typical antipsychotics (e.g. haloperidol) reverse ppi deficits induced by dopamine (da) agonists (e.g. apomorphine), but not those induced by n-methyl- d-aspartate (nmda) receptor antago ... | 2003 | 12845408 |
| distribution of nadph-diaphorase in the superior colliculus of cebus monkeys, and co-localization with calcium-binding proteins. | we examined the distribution of the enzyme dihydronicotinamide adenine dinucleotide phosphate-diaphorase (nadph-d) in the superior colliculus (sc) of the new world monkey cebus apella, and the co-localization of this enzyme with the calcium-binding proteins (cabps) calbindin-d28k, parvalbumin and calretinin. despite the intensely labeled neuropil, rare nadph-d-positive cells were observed in the stratum griseum superficiale (sgs). most of the labeled cells in the sc were found in the intermediat ... | 2003 | 12871769 |
| tufted capuchins (cebus apella) attribute value to foods and tools during voluntary exchanges with humans. | this research examined exchange and value attribution in tufted capuchin monkeys ( cebus apella). we presented subjects with opportunities to obtain various foods and a tool from an experimenter in exchange for the foods or tool in the subjects' possession. the times elapsed before the first chow biscuits were expelled and/or an exchange took place were recorded as the dependent measures. laboratory chow biscuits, grapes, apples, and a metal bolt (a tool used to probe for syrup) were used as exp ... | 2004 | 12884078 |
| abstract-concept learning and list-memory processing by capuchin and rhesus monkeys. | three capuchin monkeys (cebus apella) touched the lower of 2 pictures (same) or a white rectangle (different), increased same/different abstract-concept learning (52% to 87%) with set-size increases (8 to 128 pictures), and were better than 3 rhesus monkeys (macaca mulatta). three other rhesus that touched the top picture before choices learned similar to capuchins but were better at list-memory learning. both species' serial position functions were similar in shape and changes with retention de ... | 2003 | 12884678 |
| how do tufted capuchin monkeys (cebus apella) understand causality involved in tool use? | four tufted capuchin monkeys (cebus apella) were trained to choose from 2 hook-like tools, 1 of which successfully led to collecting food, whereas the other did not because of inappropriate spatial arrangement of the tool and the food. in experiment 1, all of the monkeys successfully learned the basic task. the monkeys performed successfully with tools of novel colors and shapes in experiments 2-5. these results demonstrate that the monkeys used the spatial arrangement of the tool and the food a ... | 2003 | 12884682 |
| a capuchin monkey (cebus apella) recognizes when people do and do not know the location of food. | in a previous study, kuroshima and colleagues demonstrated that capuchin monkeys (cebus apella) learned to discriminate between a "knower" who inspected a box for food, and a "guesser" who did not. the aim of the present study was to specify whether the subjects learned a simple conditional discrimination or a causal relationship that seeing leads to knowing. in experiment 1, we introduced five types of novel containers to two subjects. each container was of different shape and color. the subjec ... | 2003 | 12905080 |
| coexistence of gad-65 and gad-67 with tyrosine hydroxylase and nitric oxide synthase in amacrine and interplexiform cells of the primate, cebus apella. | the expression of glutamate decarboxylase forms, gad-65 and gad-67, in gabaergic cells was studied by immunocytochemistry in the retina of the new world monkey, cebus apella. in the innermost rows of the inner nuclear layer (inl), somata that express gaba correspond to about 45% of the total number of cells in the central retina and about 25% on the periphery. three subsets of gabaergic amacrine cells were identified along the horizontal meridian: about 5% express only gad-65 and 40% gad-67, and ... | 2003 | 12916737 |
| morphometry and histochemistry of the semitendinosus muscle of tufted capuchin monkeys (cebus apella linnaeus, 1758). | considering monkeys are animals closely related to the human, and semitendinosus muscle has been used in many postural research experiments, we have decided to study its histochemical characteristics. samples were removed from the proximal, middle and distal regions of the semitendinosus muscles of five adult male tufted capuchin monkeys and observed for reaction with m-atpase (with alkaline and acid pre-incubation), nicotinamide adenine dinucleotide tetrazolium reductase, and haematoxylin and e ... | 2003 | 12919070 |
| ngfi-a immunoreactivity in the primate retina: implications for genetic regulation of plasticity. | in rodents, enriched environments drive the expression of the immediate early gene ngfi-a, a regulator of the plasticity marker synapsin i. both proteins have been implicated as mediators of plasticity in the rat mammalian retina. in the present work immunocytochemistry directed against these proteins was used to explore their basal activity in the retina of a more visual species, the new world monkey cebus apella. in contrast to rat, monkey retina displayed high basal expression of both ngfi-a ... | 2003 | 12959744 |
| monkeys reject unequal pay. | during the evolution of cooperation it may have become critical for individuals to compare their own efforts and pay-offs with those of others. negative reactions may occur when expectations are violated. one theory proposes that aversion to inequity can explain human cooperation within the bounds of the rational choice model, and may in fact be more inclusive than previous explanations. although there exists substantial cultural variation in its particulars, this 'sense of fairness' is probably ... | 2003 | 13679918 |
| [susceptibility of cebus apella macrocephalus spix 1823, to experimental schistosoma mansoni infection]. | | 1962 | 13872809 |
| [the degree of ossification in a newborn fullterm capuchin monkey (cebus apella)]. | | 1963 | 13991768 |
| throwing behavior and mass distribution of stone selection in tufted capuchin monkeys (cebus apella). | cannell [journal of archaeological science 29:335-339, 2002] argued that sex-based differences among humans in terms of the mass of chosen throwing stones could be used to infer body mass and patterns of sexual dimorphism in early hominids from olduvai and koobi fora by examining the mass distributions of unaltered stone tools at those sites. we examined this hypothesis in tufted capuchin monkeys using a comparative approach, by investigating the relationships among body mass, sex, stone weight ... | 2003 | 14669268 |
| utilization of autogenous bone, bioactive glasses, and calcium phosphate cement in surgical mandibular bone defects in cebus apella monkeys. | the purpose of the present study was to evaluate the histologic results of bone cavities that were surgically created in the mandibles of cebus apella monkeys and filled with autogenous bone, perioglas, fillerbone, or bone source. | 2004 | 14982358 |
| do squirrel monkeys (saimiri sciureus) and capuchin monkeys (cebus apella) predict that looking leads to touching? | squirrel monkeys (saimiri sciureus) and capuchin monkeys (cebus apella) were tested using an expectancy violation procedure to assess whether they use an actor's gaze direction, signaled by congruent head and eye orientation, to predict subsequent behavior. the monkeys visually habituated to a repeated sequence in which the actor (a familiar human or a puppet) looked at an object and then picked it up, but they did not react strongly when the actor looked at an object but then picked up another ... | 2004 | 15022054 |
| transport of tools to food sites in tufted capuchin monkeys (cebus apella). | tool use and transport represent cognitively important aspects of early hominid evolution, and nonhuman primates are often used as models to examine the cognitive, ecological, morphological and social correlates of these behaviors in order to gain insights into the behavior of our early human ancestors. in 2001, jalles-filho et al. found that free-ranging capuchin monkeys failed to transport tools (stones) to food sites (nuts), but transported the foods to the tool sites. this result cast doubt ... | 2004 | 15022055 |
| cytoarchitecture and musculotopic organization of the facial motor nucleus in cebus apella monkey. | the architecture and musculotopic organization of the facial motor nucleus in the cebus apella monkey (a new world primate) were investigated using histological techniques and a multiple labelling strategy, in which horseradish peroxidase-conjugated neuroanatomical tracers (ctb-hrp and wga-hrp) and fluorescent tracers were injected into individual facial muscles. the facial motor nucleus was formed by multipolar motoneurons and had an ovoid shape, with its rostrocaudal axis measuring on average ... | 2004 | 15032907 |
| reactions of capuchin monkeys (cebus apella) to multiple mirrors. | this study attempted a new manipulation to prompt mirror self-recognition in a monkey species through simultaneous exposure to two mirrors. four capuchin monkeys (cebus apella) were exposed to one large and one small mirror object with different reflective or configurational properties, which was thought to deepen their understanding of mirrors. the monkeys predominantly engaged in looking behaviours towards the large mirror, which decreased over sessions. there was also an increase in looking b ... | 2004 | 15062965 |
| post-coital administration of levonorgestrel does not interfere with post-fertilization events in the new-world monkey cebus apella. | experimental evidence to disprove the belief that emergency contraception with levonorgestrel (lng) prevents pregnancy by interfering with post-fertilization events is lacking. here we determined the effect of post-coital and pre-ovulatory administration of lng on fertility and ovulation, respectively, in the cebus monkey. | 2004 | 15105392 |
| discrimination of functionally appropriate and inappropriate throwing tools by captive tufted capuchins (cebus apella). | a tool-throwing task was used to test whether capuchin monkeys understand the difference between functionally appropriate and functionally inappropriate tools. a group of monkeys was trained to obtain a sticky treat from a container outside their enclosure using a projectile attached to one end of an anchored line. subsequently, these monkeys were given choice tests between functional and nonfunctional versions of tools used in training. a different feature of the tool was varied between alterna ... | 2004 | 15138849 |
| socially biased learning in monkeys. | we review socially biased learning about food and problem solving in monkeys, relying especially on studies with tufted capuchin monkeys (cebus apella) and callitrichid monkeys. capuchin monkeys most effectively learn to solve a new problem when they can act jointly with an experienced partner in a socially tolerant setting and when the problem can be solved by direct action on an object or substrate, but they do not learn by imitation. capuchin monkeys are motivated to eat foods, whether famili ... | 2004 | 15161138 |
| predation of crabs by tufted capuchins (cebus apella) in eastern amazonia. | | 2004 | 15240980 |
| socially learned preferences for differentially rewarded tokens in the brown capuchin monkey (cebus apella). | social learning is assumed to underlie traditions, yet evidence indicating social learning in capuchin monkeys (cebus apella), which exhibit traditions, is sparse. the authors tested capuchins for their ability to learn the value of novel tokens using a previously familiar token-exchange economy. capuchins change their preferences in favor of a token worth a high-value food reward after watching a conspecific model exchange 2 differentially rewarded tokens, yet they fail to develop a similar pre ... | 2004 | 15250800 |
| grasping behavior in tufted capuchin monkeys (cebus apella): grip types and manual laterality for picking up a small food item. | this study investigates prehension in 20 tufted capuchins (cebus apella) in a reaching task requiring individuals to grasp a small food item fixed to a tray. the aim was twofold: 1) to describe capuchins' grasping techniques in detail, focusing on digit movements and on different areas of contact between the grasping fingers; and 2) to assess the relationship between grip types and manual laterality in this species. capuchins picked up small food items using a wide variety of grips. in particula ... | 2004 | 15293329 |
| a natural asymptomatic herpes b virus infection in a colony of laboratory brown capuchin monkeys (cebus apella). | herpes b virus (bv) infection of macaques persists in the natural host, but is mainly asymptomatic. however, bv can cause fatal disease in humans and in several non-macaque species such as capuchin monkeys (cebus apella). the bv infection described here in a colony of capuchin monkeys was persistent but asymptomatic. initially the infection was detected serologically in five out of seven animals. however, using polymerase chain reaction (pcr) developed specifically for bv, we found the virus in ... | 2004 | 15479559 |
| detection of grouped and ungrouped parts in visual patterns by tufted capuchin monkeys (cebus apella) and humans (homo sapiens). | the authors investigated perceptual grouping in capuchin monkeys (cebus apella) and humans (homo sapiens). in experiment 1, 6 monkeys received a visual pattern as the sample and had to identify the comparison stimulus featuring some of its parts. performance was better for ungrouped parts than for grouped parts. in experiment 2, the sample featured the parts, and the comparison stimuli, the complex figures: the advantage for ungrouped elements disappeared. in experiment 3, in which new stimuli w ... | 2004 | 15482057 |
| a concept of value during experimental exchange in brown capuchin monkeys, cebus apella. | we evaluated the response of brown capuchin monkeys to two differentially valued tokens in an experimental exchange situation akin to a simple barter. monkeys were given a series of three tests to evaluate their ability to associate tokens with food, then their responses were examined in a barter situation in which tokens were either limited or unlimited. capuchins did not perform barter in the typical sense, returning the tokens which were associated with the reward. however, females, but not m ... | 2004 | 15486443 |
| posture and reaching in tufted capuchins (cebus apella). | this research investigated the effects of posture on lateral bias for food reaching in tufted capuchin monkeys ( cebus apella ) by comparing hand preferences for quadrupedal and bipedal reaching. several findings of this investigation warrant discussion. first, we found a population-level bias towards use of the right hand for bipedal reaching but not for quadrupedal reaching. second, adults exhibited a greater right-hand preference for bipedal reaching than did immatures. third, subjects showed ... | 1997 | 15513054 |
| manual exploratory procedures and asymmetries for a haptic search task: a comparison between capuchins (cebus apella) and humans. | left-hand preferences in monkeys (capuchins, macaques) for haptic discriminations have been taken to indicate that the right hemisphere is more involved than the left hemisphere in solving these tasks. we confirmed this left-hand bias in a group of 21 capuchins haptically searching for sunflower seeds located in crevices in 12 different objects (lacreuse & fragaszy, 1996). in an attempt to specify the relations of the left-hand bias to hand performance and hemispheric lateralisation, we analysed ... | 1997 | 15513067 |
| left hand preferences in capuchins (cebus apella): role of spatial demands in manual activity. | sixteen capuchins (cebus apella) participated in four tasks that differed in their exploration demands and availability of visual cues. the two explorative tasks required the monkeys to discover sunflower seeds hidden in crevices in objects of various shapes, with vision (haptic-visual task) or without vision (haptic task). two other tasks required the capuchins to grasp sunflower seeds directly on a flat support, with vision (visual reaching) or without vision (tactual reaching). the presence o ... | 1999 | 15513105 |
| evolutionary breakpoints are co-localized with fragile sites and intrachromosomal telomeric sequences in primates. | the concentration of evolutionary breakpoints in primate karyotypes in some particular regions or chromosome bands suggests that these chromosome regions are more prone to breakage. this is the first extensive comparative study which investigates a possible relationship of two genetic markers (intrachromosomal telomeric sequences [ttaggg]n, [itss] and fragile sites [fss]), which are implicated in the evolutionary process as well as in chromosome rearrangements. for this purpose, we have analyzed ... | 2005 | 15545736 |
| categorization of above and below spatial relations by tufted capuchin monkeys (cebus apella). | using a matching-to-sample procedure, the researchers investigated tufted capuchins' (cebus apella) ability to form categorical representations of above and below spatial relations. in experiment 1, 5 capuchins correctly matched bar-dot stimuli on the basis of the relative above and below location of their constituent elements. the monkeys showed a positive transfer of performance both when the bar-dot distance in the two comparison stimuli differed from that of the sample and when the actual lo ... | 2004 | 15584777 |
| differential expression of zif268 and c-fos in the primary visual cortex and lateral geniculate nucleus of normal cebus monkeys and after monocular lesions. | the transcription factors c-fos and zif268 have been used as markers of neuronal activity, and they also have been implicated in neuronal plasticity. in this study, we investigated the expression of c-fos and zif268 proteins in the lateral geniculate nucleus (lgn) and in the cortical primary visual area (v1) of normal adult cebus apella monkeys and in animals with monocular lesions. in the lgn, the reaction for c-fos showed immunopositive cells in both magnocellular (m) and parvocellular (p) lay ... | 2005 | 15611990 |
| are monkeys aesthetists? rensch (1957) revisited. | three experiments assessed whether capuchin monkeys (cebus apella) and squirrel monkeys (saimiri sciureus) prefer regular and symmetrical visual patterns. pictorial representations of faces were included in 1 stimulus set. when the monkeys could pick up and manipulate small cards bearing the stimuli, all preferences expressed by capuchins and most of those expressed by squirrel monkeys were for regular stimuli. symmetry of the patterns was influential but not essential. some preferences were als ... | 2005 | 15656728 |
| ordinal representation of numeric quantities by brown capuchin monkeys (cebus apella). | using techniques established by e. m. brannon and h. s. terrace (2000) with rhesus macaques (macaca mulatta), the authors tested the ability of brown capuchins (cebus apella) to order arrays of items ranging in quantity from 1 to 9. three monkeys were trained on a touch screen to select the quantities 1-4 in ascending order. the monkeys exhibited successful transfer of this ability to novel representations of the quantities 1-4 and to pairs of the novel quantities 5-9. patterns of responding wit ... | 2005 | 15656729 |
| changes of ongoing activity in cebus monkey perirhinal cortex correlate with behavioral performance. | a cebus apella monkey weighing 4 kg was trained in a saccadic eye movement task and while the animal performed the task we recorded the extracellular activity of perirhinal cortical neurons. although the task was very simple and maintained at a constant level of difficulty, we observed considerable changes in the performance of the monkey within each experimental session. the behavioral states responsible for such variation may be related to arousal, motivation or attention of the animal while e ... | 2005 | 15665990 |
| comparison of iron chelator efficacy in iron-overloaded beagle dogs and monkeys (cebus apella). | rodents and dogs are frequently used for preclinical toxicologic assessment of candidate iron chelators. although the iron-clearing profile of a ligand often is known in rodents, and sometimes in primates, such information in dogs is rarely, if ever, available. because of this, toxicity studies in dogs could be misleading; chelators that may otherwise be suitable for human clinical studies may be abandoned as being unacceptably toxic, simply because, unknown to the investigator, these drugs remo ... | 2004 | 15679265 |
| partition-variant desferrithiocin analogues: organ targeting and increased iron clearance. | altering the lipophilicity (log p(app)) of desferrithiocin analogues can change the organ distribution of the chelators and lead to enhanced iron clearance. for example, alkylation of (s)-2-(2,4-dihydroxyphenyl)-4,5-dihydro-4-methyl-4-thiazolecarboxylic acid [(s)-4'-(ho)-dadft] and its analogues to more lipophilic compounds, such as (s)-4,5-dihydro-2-(2-hydroxy-4-methoxyphenyl)-4-methyl-4-thiazolecarboxylic acid [(s)-4'-(ch3o)-dadft], provides ligands that achieved between a 3- and 8-fold increa ... | 2005 | 15689166 |
| tolerance for inequity may increase with social closeness in chimpanzees. | economic decision-making depends on our social environment. humans tend to respond differently to inequity in close relationships, yet we know little about the potential for such variation in other species. we examine responses to inequity in several groups of chimpanzees (pan troglodytes) in a paradigm similar to that used previously in capuchin monkeys (cebus apella). we demonstrate that, like capuchin monkeys, chimpanzees show a response to inequity of rewards that is based upon the partner r ... | 2005 | 15705549 |