Publications

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spontaneous cholangiocarcinoma in a ring-tailed lemur (lemur catta).a cholangiocarcinoma in the liver with metastasis to the regional lymph nodes was found in a male ring-tailed lemur (lemur catta). the liver was partially replaced by a gray-white, coarsely lobulated mass. microscopically, the tumor consisted of well circumscribed lobules of anaplastic, low cuboidal cells occasionally arranged in duct-like structures. the tumor did not involve the gallbladder.1979228114
the reproductive cycle of the ring-tailed lemur (lemur catta): sex steroid levels and sexual receptivity under controlled photoperiods. 1977410632
induction of estrus in intact lemur catta under photoinhibition of ovarian cycles. 1977408831
diurnal variations of plasma testosterone in two prosimian primates (galago crassicaudatus crassicaudatus and lemur catta). 1976823984
composition of lemur milk.the average composition of 8 samples of milk from lemur catta, l. fulvus, l. macaco and a hybrid lemur was (in g/100 mt): lipids, 2.3; protein, 2.7; lactose, 6.4; and ash, 0.35. the fatty acids and major minerals were also quantified. the results did not support classification of l. fulvus and l. macao within the same species.1976827483
olfactory and visual cues in social interactions of lemur catta.the relationship between visual and olfactory cues and their relative importance in interactions between pairs of adult male ring-tailed lemurs was determined. visual and olfactory contact was controlled. when visualcontact was prevented. little behavior occurred. when visual contact was permitted, olfactory cues altered behavior.1976821832
hydatid disease in four nonhuman primates.hydatid disease was detected in 4 nonhuman primates (galago crassicaudatus, lemur catta, and 2 macaca mulatta) at the oregon regional primate research center. involvement extended from 2 1/2 to 7 1/2 years. a 6-cm cyst was surgically removed from the thoracic cavity of 1 macaque; 6 years later multiple cysts were found in its abdominal cavity. lesions found in the primates at necropsy included compression or displacement of the lungs, hydroureter and hydronephrosis, and distension of the abdomen ...1975809387
primate breeding season: photoperiodic regulation in captive lemur catta.under natural light in portland, oreg., captive ring-tailed lemurs (lemur catta) experience a breeding season that differs by nearly half a year from the season in madagascar. a series of experimental day length changes from 1971 to 1974 demonstrated the ability of both temperate and tropical photoperiod cycles to induce estrous cycles in quiescent animals. after photoperiodic activation, most impregnated females failed to resume estrous cycles even after infant separations unless they received ...1975809326
[cytogenetic study of lemur catta]. 19704990837
[the role of testosterone in the determinism of the brachial and antebrachial glands of the lemur catta]. 19684238211
[some studies on the behavior of lemur catta]. 19674386897
fine structure of the sweat glands of the antebrachial organ of lemur catta. 19665986740
the skin of primates. x. the skin of the ring-tailed lemur (lemur catta). 196214475446
a sarcoma of bone in a ring-tailed lemur (lemur catta). 195114874165
mycobacterium leprae genomes from naturally infected nonhuman primates.leprosy is caused by the bacterial pathogens mycobacterium leprae and mycobacterium lepromatosis. apart from humans, animals such as nine-banded armadillos in the americas and red squirrels in the british isles are naturally infected with m. leprae. natural leprosy has also been reported in certain nonhuman primates, but it is not known whether these occurrences are due to incidental infections by human m. leprae strains or by m. leprae strains specific to nonhuman primates. in this study, compl ...201829381722
energy (im-)balance in frugivorous lemurs in southern madagascar: a preliminary study in lemur catta and eulemur rufifrons × collaris.the reproductive cycle of several lemur species is synchronized by photoperiodic changes and it is attuned to the seasonal fluctuations in food supply. nevertheless, irregular periods of food shortage occur in madagascar, which can result in a negative energy balance and reduced fitness, especially in frugivorous species. here, we tested whether ring-tailed lemurs (lemur catta) and brown lemurs (eulemur rufifrons × collaris) use fat stores to maintain their energy balance in a gallery forest of ...201830286458
comparison of the glucocorticoid concentrations between three species of lemuridae kept in a temporary housing facility.we compared the glucocorticoid concentrations in response to various types of potential stressors present during standard operation of a temporary housing facility between three species, namely, ring-tailed lemurs, collared brown lemurs and white-headed lemurs. the levels of faecal glucocorticoid metabolites (fgms) were measured non-invasively on a daily basis during a 30-day period. a total of 510 faecal samples were collected. concentrations of immunoreactive glucocorticoid hormone metabolites ...202032532091
a study of locomotor behavior in a captive colony of red-bellied lemurs (eulemur rubriventer).the considerable diversity of locomotor behavior within the suborder prosimii largely is due to differences in locomotion between families. within families, locomotion is relatively homogeneous, although some species, such as otolemur crassicaudatus among the galagids and hapalemur simus and lepilemur spp. among the lemurids, differ from other species in their family. this paper describes the locomotion of a captive colony of red-bellied lemurs, eulemur rubriventer (following the classification ...199031963961
curious creatures: a multi-taxa investigation of responses to novelty in a zoo environment.the personality trait of curiosity has been shown to increase welfare in humans. if this positive welfare effect is also true for non-humans, animals with high levels of curiosity may be able to cope better with stressful situations than their conspecifics. before discoveries can be made regarding the effect of curiosity on an animal's ability to cope in their environment, a way of measuring curiosity across species in different environments must be created to standardise testing. to determine t ...201829568703
intraspecific macroscopic digestive anatomy of ring-tailed lemurs (lemur catta), including a comparison of frozen and formalin-stored specimens.digestive tract measurements are often considered species specific, but little information exists on the degree to which they change during ontogeny within a species. additionally, access to anatomical material from nondomestic species is often limited, with fixed tissues possibly representing the only available source, though the degree to which this material is representative in terms of dimensions and weight is debatable. in the present study, the macroscopic anatomy of the digestive tract (l ...202033180215
the lemur baseline: how lemurs compare to monkeys and apes in the primate cognition test battery.primates have relatively larger brains than other mammals even though brain tissue is energetically costly. comparative studies of variation in cognitive skills allow testing of evolutionary hypotheses addressing socioecological factors driving the evolution of primate brain size. however, data on cognitive abilities for meaningful interspecific comparisons are only available for haplorhine primates (great apes, old- and new world monkeys) although strepsirrhine primates (lemurs and lorises) ser ...202033024643
long-term management of congestive heart failure secondary to mitral stenosis in a ring-tailed lemur (lemur catta).a 15-year-old sexually intact female ring-tailed lemur (lemur catta) was evaluated for a heart murmur and progressive radiographic cardiomegaly.202033021447
genetic population structure of endangered ring-tailed lemurs (lemur catta) from nine sites in southern madagascar.madagascar's ring-tailed lemurs (lemur catta) are experiencing rapid population declines due to ongoing habitat loss and fragmentation, as well as increasing exploitation for bushmeat and the illegal pet trade. despite being the focus of extensive and ongoing behavioral studies, there is comparatively little known about the genetic population structuring of the species. here, we present the most comprehensive population genetic analysis of ring-tailed lemurs to date from across their likely rema ...202032788959
food preferences and nutrient composition in zoo-housed ring-tailed lemurs, lemur catta.the aim of the present study was to assess the occurrence of spontaneous food preferences in zoo-housed ring-tailed lemurs and to analyze whether these preferences correlate with nutrient composition. using a two-alternative choice test three female and one male lemur catta were repeatedly presented with all possible binary combinations of 12 types of food which are part of their diet in captivity and found to display the following rank order of preference: apple > sweet potato > melon > beetroo ...202032771504
affiliative contact calls during group travel: chirp and wail vocalization use in the male ring-tailed lemur (lemur catta).affiliative vocalizations occur across primate taxa and may be used to maintain spatial cohesion and/or to regulate social interactions in group-living species. for gregarious strepsirhines like the ring-tailed lemur (lemur catta), with large vocal repertoires and several distinct affiliative vocalizations including the chirp and wail, it is important to understand behavioural usage of these vocalizations to gain insight into their social interactions. to determine whether chirp and wail vocaliz ...202032756063
social influences on food avoidance in lemur catta.previous primate research has demonstrated social learning related to accepting novel foods, but little evidence suggests social learning of food avoidance. ring-tailed lemurs (lemur catta)have been observed to shake their heads rapidly in response to sour and bitter stimuli. this study investigated whether this head-shaking behavior may have a social function. the experiment presented a performing lemur with two items of the same type of fruit, one of which had been manipulated to take on a sou ...202032726785
combination of intramuscular alfaxalone, butorphanol, and midazolam as a novel immobilization protocol in 3 ring-tailed lemurs (lemur catta).there is very little data on the optimal anaesthetic management of ring-tailed lemurs, and the available information is mostly based on extrapolation from other species. in addition, a thorough pre-anaesthetic assessment of lemurs might not be possible without prior chemical immobilization, making a safe immobilization protocol essential.202032551091
thoracic radiography and transthoracic echocardiography in clinically healthy ring-tailed lemurs (lemur catta).cardiac disease has been recognized as a major cause of death in captive nonhuman primates, which necessitates diagnostic (imaging) techniques to screen for and diagnose preclinical and clinical stages of possible cardiac conditions. echocardiography is currently the most commonly used diagnostic tool for evaluation of cardiac anatomy and function. complete with thoracic radiography and blood levels of two cardiac biomarkers, n-terminal probrain natriuretic peptide (nt-probnp) and cardiac tropon ...202032549560
stable and transient structural variation in lemur vaginal, labial and axillary microbiomes: patterns by species, body site, ovarian hormones and forest access.host-associated microbiomes shape and are shaped by myriad processes that ultimately delineate their symbiotic functions. whereas a host's stable traits, such as its lineage, relate to gross aspects of its microbiome structure, transient factors, such as its varying physiological state, relate to shorter term, structural variation. our understanding of these relationships in primates derives principally from anthropoid studies and would benefit from a broader, comparative perspective. we thus ex ...202032401310
key male glandular odorants attracting female ring-tailed lemurs.among rodents, information about the external world is mainly acquired via the olfactory system, which is one of five sensory modalities. several semiochemical signals are used for inter- and intraspecies communication [1]. in contrast, primates are generally regarded as vision-oriented mammals, and have been thought to trade their olfactory sensitivity for good sight. however, strepsirrhines have a well-developed olfactory system [2] and a larger repertoire of functional olfactory and vomeronas ...202032302584
do lemurs know when they could be wrong? an investigation of information seeking in three species of lemur (lemur catta, eulemur rubriventer, and varecia variegata).a total of 16 lemurs, including representatives from three species (lemur catta, eulemur rubriventer, and varecia variegata), were presented with a food-seeking task in which information about the rewards location, in one of two plastic tubes, was either known or not known. we evaluated whether lemurs would first look into the tube before making a choice. this information-seeking task aimed to assess whether subjects would display memory awareness, seeking additional information when they became ...202032011154
lemur catta in small forest fragments: which variables best predict population viability?habitat fragmentation is an increasingly serious issue affecting primates in most regions where they are found today. populations of lemur catta (ring-tailed lemur) in madagascar's south-central region are increasingly restricted to small, isolated forest fragments, surrounded by grasslands or small-scale agriculture. our aim was to evaluate the potential for population viability of l. catta in nine forest fragments of varying sizes (2-46 ha, population range: 6-210 animals) in south-central mad ...202032003047
molecular characterization of trichuris spp. from captive animals based on mitochondrial markers.monoxenous parasites may easily infect animals in captivity, and nematodes belonging to the genus trichuris are commonly reported in zoological gardens worldwide. infections in captive animals should be accurately monitored and the characterization of pathogens is highly advisable, as a tool to infer possible routes of intra- and interspecific transmission pathways and to assess the related zoonotic potential. whipworms are usually identified on the basis of few morphological features of adults ...202031881362
gibbons exploit information about what a competitor can see.how much nonhuman animals understand about seeing has been the focus of comparative cognition research for decades. many social primates (and other species) are sensitive to cues about what others can and cannot see. whether this sensitivity evolved in primates through shared descent or convergent evolution remains unclear. the current study tested gibbons-the apes that are least studied yet most distantly related to humans and one of the less social primates-in two food-competition tasks. speci ...202031781885
eulerian videography technology improves classification of sleep architecture in primates.sleep is a critically important dimension of primate behavior, ecology, and evolution, yet primate sleep is under-studied because current methods of analyzing sleep are expensive, invasive, and time-consuming. in contrast to electroencephalography (eeg) and actigraphy, videography is a cost-effective and non-invasive method to study sleep architecture in animals. with video data, however, it is challenging to score subtle changes that occur in different sleep states, and technology has lagged be ...201931456082
genetic variation at mhc class ii loci influences both olfactory signals and scent discrimination in ring-tailed lemurs.diversity at the major histocompatibility complex (mhc) is critical to health and fitness, such that mhc genotype may predict an individual's quality or compatibility as a competitor, ally, or mate. moreover, because mhc products can influence the components of bodily secretions, an individual's body odors may signal its mhc composition and influence partner identification or mate choice. here, we investigated mhc-based signaling and recipient sensitivity by testing for odor-gene covariance and ...201931438845
organizational and activational androgens, lemur social play, and the ontogeny of female dominance.the role of androgens in shaping "masculine" traits in males is a core focus in behavioral endocrinology, but relatively little is known about an androgenic role in female aggression and social dominance. in mammalian models of female dominance, including the ring-tailed lemur (lemur catta), links to androgens in adulthood are variable. we studied the development of ring-tailed lemurs to address the behavioral basis and ontogenetic mechanisms of female dominance. we measured behavior and serum a ...201931276664
a natural point mutation in the bitter taste receptor tas2r16 causes inverse agonism of arbutin in lemur gustation.bitter taste enables the detection of potentially harmful substances and is mediated by bitter taste receptors, tas2rs, in vertebrates. few antagonists and inverse agonists of tas2rs have been identified, especially natural compounds. tas2r16s in humans, apes and old world monkeys (catarrhini, anthropoidea) recognize β-glucoside analogues as specific agonists. here, we investigated responses of tas2r16 to β-glucosides in non-anthropoid primates, namely lemurs (lemuriformes, strepsirrhini). salic ...201931161904
illegal trade of wild-captured lemur catta within madagascar.lemur catta is the most reported illegal captive lemur. we document 286 l. catta that were held in illegal captive conditions in madagascar. coastal tourist destinations are "hot spots" for sightings. many of the l. catta reported were in businesses (49%) and were perceived to be held captive for the purpose of generating income (41%). infant/juvenile l. catta were overwhelmingly observed annually in december (41%) and may suffer high mortality rates given that they are not weaned during this mo ...201931067551
heteropaternity of twins in ring-tailed lemurs (lemur catta).this project investigated paternity among 14 sets of twins born into a colony of ring-tailed lemurs (lemur catta) on st. catherines island, ga. female l. catta commonly mate with >1 male, and twins of different sexes confirm that dizygotic twinning can occur in this species. however, no study has previously evaluated twins using genetic data to measure the proportion of mono versus dizygotic twinning in l. catta, and no study has tested for heteropaternity (sirehood by two different males) in th ...201930951607
captive ring-tailed lemur breeding in semi-free ranging conditions and genetic parentage analysis.the ring-tailed lemur (lemur catta), one of the most iconic and widely recognized primates in the world, is threatened in its native range and classified as endangered by the international union for conservation of nature. the global conservation strategy for the species includes ex situ conservation efforts led by zoological institutions in the framework of regional captive breeding programs. to maximize the conservation of genetic diversity and optimize breeding programs, an accurate pedigree ...201930888079
pitch control and speed limitation during overground deceleration in lemurid primates.an animal's fitness is influenced by the ability to move safely through its environment. recent models have shown that aspects of body geometry, for example, limb length and center of mass (com) position, appear to set limits for pitch control in cursorial quadrupeds. models of pitch control predict that the body shape of these and certain other primates, with short forelimbs and posteriorly positioned com, should allow them to decelerate rapidly while minimizing the risk of pitching forward. we ...201930653715
a viral video and pet lemurs on twitter.content shared on social media platforms can impact public perceptions of wildlife. these perceptions, which are in part shaped by context (e.g. non-naturalistic setting, presence of a human), can influence people's desires to interact with or acquire wild animals as pets. however, few studies have examined whether this holds true for wild animals featured in viral videos. this study reports on opportunistic data collected on twitter before, during, and after a video that featured a habituated r ...201930625137
getting into shape: limb bone strength in perinatal lemur catta and propithecus coquereli.functional studies of skeletal anatomy are predicated on the fundamental assumption that form will follow function. for instance, previous studies have shown that the femora of specialized leaping primates are more robust than those of more generalized primate quadrupeds. are such differences solely a plastic response to differential loading patterns during postnatal life, or might they also reflect more canalized developmental mechanisms present at birth? here, we show that perinatal lemur catt ...202030548126
systemic yersinia pseudotuberculosis as a cause of osteomyelitis in a captive ring-tailed lemur (lemur catta).yersinia pseudotuberculosis and yersinia enterocolitica are ubiquitous pathogens with wildlife and domestic animal reservoirs. outbreaks of 'non-plague' yersiniosis in man and non-human primates are reported frequently (including zoological specimens and research breeding colonies) and are usually characterized by enteritis, mesenteric lymphadenitis and occasionally organ abscessation. in people, non-septic reactive arthritis is a common sequela to yersiniosis. however, there have been rare repo ...201830360909
do forelimb shape and peak forces co-vary in strepsirrhines?in this study, we explore whether ground reaction forces recorded during horizontal walking co-vary with the shape of the long bones of the forelimb in strepsirrhines. to do so, we quantify (1) the shape of the shaft and articular surfaces of each long bone of the forelimb, (2) the peak vertical, mediolateral, and horizontal ground reaction forces applied by the forelimb during arboreal locomotion, and (3) the relationship between the shape of the forelimb and peak forces.201830159895
instrumental problem-solving abilities in three lemur species (microcebus murinus, varecia variegata, and lemur catta).apes and some new and old world monkeys (i.e., haplorhine primates) are known to routinely use tools. in strepsirrhine primates (i.e., lemurs and lorises), no tool use has been reported, even though they appear to have some basic understanding of the spatial relations required for using a pulling tool. to facilitate direct comparisons of the underlying abilities between haplorhine and strepsirrhine primate species, we experimentally examined instrumental problem-solving abilities in three captiv ...201830080072
restating the case for a sharp population decline in lemur catta.as with many other species in the primate order, ring-tailed lemurs (lemur catta) are threatened with extinction. our articles documented declines in wild ring-tailed lemur populations and noted that fewer than 2,500 wild ring-tailed lemurs are known to persist in 32 [gould and sauther: primate conservation 2016; 30: 89-101] and 34 [lafleur et al.: folia primatologica 2017; 87: 320-330] sites. a criticism of our articles [murphy et al.: international journal of primatology 2017; 38: 623-628] sug ...201830045037
costs of injury for scent signalling in a strepsirrhine primate.honesty is crucial in animal communication when signallers are conveying information about their condition. condition dependence implies a cost to signal production; yet, evidence of such cost is scarce. we examined the effects of naturally occurring injury on the quality and salience of olfactory signals in ring-tailed lemurs (lemur catta). over a decade, we collected genital secretions from 23 (13 male, 10 female) adults across 34 unique injuries, owing primarily to intra-group fights. using g ...201829959333
sex-typed social development in lemur catta.strong chemical control of strepsirrhine mating behaviour when compared to haplorhines might suggest that strepsirrhine behavioural development, generally, is under stronger somatic control. a comparative lack of reported behavioural sex differences in immature strepsirrhines would seem to support this hypothesis, but the recent discovery of sex differences in juvenile foraging behaviour in lemur catta suggests that this difference might be an artefact of undersampling in strepsirrhines. here, i ...201829734175
behavioral responses of three lemur species to different food enrichment devices.environmental enrichment is a tool used to promote the welfare and well-being of captive animals by encouraging the display of species-specific behaviors and reducing the stress or boredom induced by captive environments. lemurs are highly endangered, yet few studies have analyzed the behavioral impacts of enrichment on captive populations. we studied the impacts of two novel enrichment devices on three lemur species (ring-tailed lemurs [lemur catta], red-ruffed lemurs [varecia rubra], and coque ...201829722911
knowledgeable lemurs become more central in social networks.strong relationships exist between social connections and information transmission [1-9], where individuals' network position plays a key role in whether or not they acquire novel information [2, 3, 5, 6]. the relationships between social connections and information acquisition may be bidirectional if learning novel information, in addition to being influenced by it, influences network position. individuals who acquire information quickly and use it frequently may receive more affiliative behavi ...201829628372
alfaxalone anaesthesia in lemur catta following dexmedetomidine-butorphanol-midazolam sedation.to evaluate the clinical effects and quality of sedation, induction, maintenance and recovery in lemur catta after dexmedetomidine-butorphanol-midazolam sedation and alfaxalone anaesthesia.201829625917
age-related changes in hematology and blood biochemistry values in endangered, wild ring-tailed lemurs ( lemur catta) at the bezà mahafaly special reserve, madagascar.the health of 44 wild ring-tailed lemurs ( lemur catta) at the bezà mahafaly special reserve was assessed across three age classes: <5 yr (young), 5-9 yr (adult), and ≥10 yr (old). hematology and biochemistry tests were performed manually (leukocyte count and differential, packed cell volume, total protein) and using a point-of-care analyzer (hematocrit, hemoglobin, glucose, blood urea nitrogen, creatinine, sodium, potassium, chloride, ionized calcium, total carbon dioxide, anion gap), respectiv ...201829517441
modeling individual vocal differences in group-living lemurs using vocal tract morphology.vocal individuality is widespread in social animals. individual variation in vocalizations is a prerequisite for discriminating among conspecifics and may have facilitated the evolution of large complex societies. ring-tailed lemurs lemur catta live in relatively large social groups, have conspicuous vocal repertoires, and their species-specific utterances can be interpreted in light of source-filter theory of vocal production. indeed, their utterances allow individual discrimination and even re ...201729492006
functional morphology of mimetic musculature in primates: how social variables and body size stack up to phylogeny.mammalian skeletal muscle is influenced by the functional demands placed upon it. functional morphology of facial expression musculature, or mimetic musculature, is largely unknown. recently, primate mimetic musculature has been shown to respond to demands associated with social factors. body size has also been demonstrated to affect many aspects of primate functional morphology and evolutionary morphology. the present study was designed to further examine the role of social variables and body s ...201829330949
the distribution of ki-67 and doublecortin-immunopositive cells in the brains of three strepsirrhine primates: galago demidoff, perodicticus potto, and lemur catta.this study investigated the pattern of adult neurogenesis throughout the brains of three prosimian primate species using immunohistochemical techniques for endogenous markers of this neural process. two species, galago demidoff and perodicticus potto, were obtained from wild populations in the primary rainforest of central africa, while one species, lemur catta, was captive-bred. two brains from each species, perfusion-fixed with 4% paraformaldehyde, were sectioned (50 µm section thickness) in s ...201829289719
the effect of extreme weather events on hair cortisol and body weight in a wild ring-tailed lemur population (lemur catta) in southwestern madagascar.madagascar is known for its hypervariable climate with periodic droughts and cyclones, but little is known of the impact of such events on lemur physiology. we examined the effects of sequential weather periods, drought, normal, cyclone and post-cyclone, on hair cortisol concentrations (hcc) and body weight in wild ring-tailed lemurs, lemur catta (n = 185), at the bezà mahafaly special reserve in southwestern madagascar. data were modeled and analyzed by sex, age, and troop. given the ecological ...201829266407
the effects of olfactory stimulation on the behavior of captive ring-tailed lemurs (lemur catta).ring-tailed lemurs reside in many animal collections worldwide. lemur welfare may be a cause of concern due to some captive individuals exhibiting stereotypic behavior. despite these concerns, there has been little exploration of methods of environmental enrichment for ring-tailed lemurs. olfactory stimulation can enhance captive animal welfare by encouraging species-typical behaviors, enhancing behavioral diversity, and decreasing stereotypic behaviors. we aimed to investigate the effects of ol ...201829239483
bamboo specialists from two mammalian orders (primates, carnivora) share a high number of low-abundance gut microbes.bamboo specialization is one of the most extreme examples of convergent herbivory, yet it is unclear how this specific high-fiber diet might selectively shape the composition of the gut microbiome compared to host phylogeny. to address these questions, we used deep sequencing to investigate the nature and comparative impact of phylogenetic and dietary selection for specific gut microbial membership in three bamboo specialists-the bamboo lemur (hapalemur griseus, primates: lemuridae), giant panda ...201829188302
the use of atracurium in an anaesthetized ring-tailed lemur (lemur catta). 201729174962
"stink flirting" in ring-tailed lemurs (lemur catta): male olfactory displays to females as honest, costly signals.sexual selection for honest behavioral displays of quality has driven the development of remarkably complex courtship behavior in many animal species. olfactory displays are often overlooked as an area of inquiry compared to auditory and visual displays. ring-tailed lemur (lemur catta) scent marking of substrates has been studied extensively, although the male olfactory displays of anointing and wafting tails to females has received relatively little attention. we studied the role of male olfact ...201729140563
genetic wealth, population health: major histocompatibility complex variation in captive and wild ring-tailed lemurs (lemur catta).across species, diversity at the major histocompatibility complex (mhc) is critical to individual disease resistance and, hence, to population health; however, mhc diversity can be reduced in small, fragmented, or isolated populations. given the need for comparative studies of functional genetic diversity, we investigated whether mhc diversity differs between populations which are open, that is experiencing gene flow, versus populations which are closed, that is isolated from other populations. ...201729043021
benign bilateral adenomyoepithelioma of the mammary gland in a ring-tailed lemur (lemur catta).naturally occurring mammary tumours are uncommon in prosimians. a 20-year-old female ring-tailed lemur (lemur catta) developed bilateral enlargement of the mammary glands. surgical removal revealed that both masses were comprised of multiple nodules and cystic areas that entirely replaced the normal glands. histologically, a benign neoplastic biphasic cellular proliferation, composed of luminal-epithelial and basal-myoepithelial components, was identified. immunohistochemical analysis for expres ...201828942309
adoption of a wild orphaned ringtailed lemur infant by natal group members: adaptive explanations.in december 1992 an infant ringtailed lemur, approximately 7 weeks of age, was orphaned in one of the regularly-censused social groups at the beza-mahafaly reserve, southwestern madagascar. the infant was initially adopted by a subadult (2 yr-old) male from the group. continuous-time focal animal data were collected for a 12-hr period, from the time that the infant was retrieved by the young male, in order to document the adoption process. ten members of the infant's social group (total group nu ...200030545205
do ringtailed lemurs (lemur catta) reconcile in the hour post-conflict?: a pilot study.a previous study bykappeler (1993) showed that no reconciliation occurred in the ringtailed lemur (lemur catta). like the majority of studies dealing with reconciliation, the post-conflict period lasted 10 minutes. an identical study using a 70-min post-conflict period was conducted on one of the same semi-free ranging group studied six years earlier bykappeler. results showed that individuals who never interacted within 10 min did engage in friendly interactions in the longer lasting postconfli ...200030545174
male-female affiliative relationships in naturally occurring ringtailed lemurs (lemur catta) at the beza-mahafaly reserve, madagascar.affiliative behavior between adult male and female ringtailed lemurs was examined as part of a project concerning male affiliation with conspecifics of all age/sex classes. males in three social groups were studied over a 12 month period. male-female preferred partnerships existed, and were variable according to reproductive season. dominance rank, age, or tenure of the male did not appear to affect either the number of partnerships or frequency of affiliative behaviors that males had with femal ...199631918491
individuality in a contact call of the ringtailed lemur (lemur catta).a vocalization of the ringtailed lemur (lemur catta) was examined for individual differences according to several temporal- and frequency-dependent variables. vocalizations were tape recorded at the duke university primate center (durham, nc) and spectrographically analyzed. significant differences were found in pair-wise comparisons of call structure among the study subjects, thus providing the physical basis for individual discrimination. a separate analysis comparing degree of kinship and voc ...198631979454
prosimian hemoglobins: iv. the structural difference responsible for the hemoglobin phenotype of lemur catta.the ring-tailed lemur, lemur catta, shows a two-component hemoglobin phenotype after alkaline electrophoresis. a difference in the amino acid sequence of the isolated α-globins was observed at position 15 (α i-gly, α ii-lys) and can account for the electrophoretic pattern of two hemoglobin components. only one other amino acid difference was found in the sequence of the two globin chains: a neutral substitution occurs at position 53 (α i-gly, α ii-ala). the complete primary structures of the dup ...198731973472
aerial maneuvers of leaping lemurs: the physics of whole-body rotations while airborne.several prosimian species begin a leap from a vertical support with their back toward the landing target. to reorient themselves from this dorsally facing, head-first lift-off to a ventrally facing, feet-first landing, the animals combine an initial twist with a partial backward somersault. cinefilms of a captive colony of ringtailed lemurs (lemur catta) revealed that during leaps from vertical poles to horizontal supports, the backward somersaulting rotations were often initiated while the anim ...198832079371
excretion of radiolabeled estradiol metabolites in the slow loris (nycticebus coucang).the excretion pattern of estradiol was studied in the slow loris nycticebus coucang) and the ring-tailed lemur (lemur catta) in order to compare steroid excretion in two representative prosimian species. daily urinary estrone conjugate measurements in the female loris provided little information when applied over prolonged periods. as a result of these negative data, a metabolic study was performed to determine if estrogen excretion patterns in the slow loris differed from those in the lemur, wh ...198832079377
lactation and care for unrelated infants in forest-living ringtailed lemurs.an adult female ringtailed lemur (lemur catta) known not to have been pregnant showed spontaneous lactation in response to twin infants born to an unrelated female. the females had met only 7 months earlier, when they and two other unrelated adult females were released from separate locations in a forest enclosure to form a new social group. three months after release, an adult male from an adjacent enclosure gained access to the new group for 1 day, the day of one female's estrus. no males had ...198931964040
photopigments underlying color vision in ringtail lemurs (lemur catta) and brown lemurs (eulemur fulvus).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) ...199331937014
infanticide among ringtailed lemurs (lemur catta) at berenty reserve, madagascar.during an intertroop encounter, an infanticide was observed in a population of ringtailed lemurs (lemur catta) at berenty reserve, madagascar. the killer was a male that had not been previously observed to mate with any females in the infant's troop. this observation, combined with other observations of infanticidal behavior by males at berenty reserve and the duke university primate center, is consistent with the hypothesis that infanticide is a reproductive tactic for some male ringtailed lemu ...199431936926
organization of white adipose tissue in lemuridae.the gross anatomy of white adipose tissue was studied in seven carcasses representing three lemurid species (lemur catta, eulemur fulvus, e. mongoz) to validate in vivo methods of assessing fatness, and to contribute to a comprehensive database on the organization of adipose tissue in mammalia. during the years preceding their deaths, subjects had been either caged or semi-provisioned under semi-captive conditions, and their body masses had been recorded several times annually. all specimens wer ...199531924060
development and social dominance among group-living primates.organisms are integrated systems whose physical and behavioral components codevelop and coevolve. ontogenetic requirements in one domain are satisfied in part by prior or concurrent developments in another. this work explores how characteristic growth patterns in two primate groups interact with ecological, social, and other life-history constraints to promote the development of particular systems of agonistic relationship. first, the markedly size-dimorphic savanna baboons are contrasted with r ...199531936944
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