Publications

blue eyes in lemurs and humans: same phenotype, different genetic mechanism.	almost all mammals have brown or darkly-pigmented eyes (irises), but among primates, there are some prominent blue-eyed exceptions. the blue eyes of some humans and lemurs are a striking example of convergent evolution of a rare phenotype on distant branches of the primate tree. recent work on humans indicates that blue eye color is associated with, and likely caused by, a single nucleotide polymorphism (rs12913832) in an intron of the gene herc2, which likely regulates expression of the neighbo ...	2009	19278018
adult play fighting and potential role of tail signals in ringtailed lemurs (lemur catta).	adult strepsirrhines have been completely neglected in the study of animal play. i focused on adult play fighting and the role of tail-play as a signal in ringtailed lemurs (lemur catta). tail-play is performed during play fighting, when lemurs anoint or, more rarely, wave their tails toward the playmate. during the prereproductive period, male and female lemurs engaged in play fighting with comparable frequencies, as was expected to occur in monomorphic species such as l. catta. the dyads showi ...	2009	19236139
visual acuity in the cathemeral strepsirrhine eulemur macaco flavifrons.	studies of visual acuity in primates have shown that diurnal haplorhines have higher acuity (30-75 cycles per degree (c/deg)) than most other mammals. however, relatively little is known about visual acuity in non-haplorhine primates, and published estimates are only available for four strepsirrhine genera (microcebus, otolemur, galago, and lemur). we present here the first measurements of visual acuity in a cathemeral strepsirrhine species, the blue-eyed black lemur (eulemur macaco flavifrons). ...	2009	19180555
a scoring system for coat and tail condition in ringtailed lemurs, lemur catta.	coat condition can be influenced by a wide variety of disorders and thus provides a useful tool for noninvasive health and welfare assessments in wild and captive animals. using lemur catta as an exemplar, we offer a 6-step scoring system for coat and tail condition, ranging from perfectly fluffy to half or more of body and tail being hairless. the categories are described in detail and illustrated with sample pictures from a wild population in berenty reserve, madagascar. furthermore, we elabor ...	2009	19142988
coat condition of ringtailed lemurs, lemur catta at berenty reserve, madagascar: i. differences by age, sex, density and tourism, 1996-2006.	an index of coat condition can be a non-invasive tool for tracking health and stress at population level. coat condition in ringtailed lemurs, lemur catta, was recorded during september-november birth seasons of 1996, 1997, 1999, and 2001-2006 at berenty reserve, madagascar. condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. adult males did not differ overall from adult females. coats were worse in adults than in 2-year-old su ...	2009	19051320
coat condition of ringtailed lemurs, lemur catta, at berenty reserve, madagascar: ii. coat and tail alopecia associated with leucaena leucocepahala, 2001-2006.	fur condition in wild ringtailed lemurs, lemur catta, was recorded during september-november birth seasons 2001-2006 at berenty reserve, madagascar. body coat condition was scored on a scale from bs 0: full, smooth coat with guard hairs, to bs5: half or more of back and limbs hairless. tail condition was scored from ts 0: full, to ts 5: half or more hairless. where troop core areas included stands of leucaena leucocephala, alopecia was dramatically more frequent than in similar areas without leu ...	2009	19051314
multimodal signaling in wild lemur catta: economic design and territorial function of urine marking.	urine marking has been neglected in prosimian primates. captive studies showed that the malagasy prosimian lemur catta scent marks with urine, as well as via specialized depositions. l. catta urine mark, a multimodal signal, differs from simple urination in terms of different design features, including tail configuration: the tail is held up during marking (ut-up) and down during urination (ut-down). we explore economy and function of ut-up in the female dominant l. catta. we collected 240 h of ...	2009	19051254
object permanence in lemurs.	object permanence, the ability to mentally represent objects that have disappeared from view, should be advantageous to animals in their interaction with the natural world. the objective of this study was to examine whether lemurs possess object permanence. thirteen adult subjects representing four species of diurnal lemur (eulemur fulvus rufus, eulemur mongoz, lemur catta and hapalemur griseus) were presented with seven standard piagetian visible and invisible object displacement tests, plus on ...	2009	18936991
dominance rank reversals and rank instability among male lemur catta: the effects of female behavior and ejaculation.	in this study, dominance rank instability among male lemur catta during mating was investigated. also, data on agonism and sexual behavior across five consecutive mating seasons in a population of l. catta on st. catherines island, usa, were collected. instances of male rank instability were categorized into three types. type 1 consisted of a temporary switch in the dominance ranks of two males, which lasted for a period of minutes or hours. type 2 dyadic male agonistic interactions showed highl ...	2009	18785630
male aggression during mating: evidence for sexual coercion in a female dominant primate?	in this article we document male sexual coercion of a lemur catta female on st. catherines island (sci), usa. data presented in this paper were collected on one free-ranging l. catta group during october-november 2002 using all-occurrences sampling for agonism and reproductive behavior. we observed a male forcefully attempting to mate with a year-old estrous female. despite the fact that we observed this female to present to the male during her estrus, throughout the episode the male employed th ...	2008	18702079
seroepidemiology of toxoplasma gondii in zoo animals in selected zoos in the midwestern united states.	toxoplasma gondii infections in zoo animals are of interest because many captive animals die of clinical toxoplasmosis and because of the potential risk of exposure of children and elderly to t. gondii oocysts excreted by cats in the zoos. seroprevalence of t. gondii antibodies in wild zoo felids, highly susceptible zoo species, and feral cats from 8 zoos of the midwestern united states was determined by using the modified agglutination test (mat). a titer of 1:25 was considered indicative of t. ...	2008	18605803
scent and the single male: ring-tailed lemurs produce honest signals.	in mating systems that involve competing males and choosy females, males are expected to advertise their genetic quality to discriminating females. most examples have focused on visual or acoustic signals, such as ornamentation or song; yet arguably, olfactory communication may be more important to the majority of vertebrates with the possible exception of birds. fortunately, attention has begun to shift to the role of odours in mate choice, with most of that attention being directed at the majo ...	2008	18564085
the asymmetric scent: ringtailed lemurs (lemur catta) have distinct chemical signatures in left and right brachial glands.	distinctive cues are predicted to evolve when the benefits obtained by the recognition process overcome its costs. when individual recognition is particularly beneficial for both senders and receivers, the expression of strongly distinctive signals is predicted to evolve. on the other hand, it could be predicted that each individual should show a very stable individual signature. in the same perspective, a great stability of the individual signatures could be expected. lemur catta is the first n ...	2008	18542901
dispersal among male ring-tailed lemurs (lemur catta) on st. catherines island.	male dispersal patterns were analyzed across a nine-year period in a population of ring-tailed lemurs (lemur catta) on st. catherines island (sci), usa, to evaluate two ultimate explanations for male dispersal: inbreeding avoidance and intrasexual mating competition. as part of this analysis, we also compared patterns of dispersal at this site with data from wild populations. overall, we found that patterns of male intertroop movement on sci are similar to the wild with respect to the frequency ...	2008	18478578
evaluation of iron status in lemurs by analysis of serum iron and ferritin concentrations, total iron-binding capacity, and transferrin saturation.	to assess serum iron and ferritin concentrations, total iron-binding capacity, and transferrin saturation as indicators of iron metabolic status in 3 genera of lemurs and determine whether these variables are useful for screening for iron overload.	2008	18279098
using extant patterns of dental variation to identify species in the primate fossil record: a case study of middle eocene omomys from the bridger basin, southwestern wyoming.	patterns of extant primate dental variation provide important data for interpreting taxonomic boundaries in fossil forms. here i use dental data from several well-known living primates (as well as data from selected eocene forms) to evaluate dental variation in middle eocene omomys, the first north american fossil primate identified by paleontologists. measurements were collected from a sample of 148 omomyid dental specimens recovered from bridger b localities in the bridger basin, wyoming. most ...	2008	18246298
a comparison of salivary ph in sympatric wild lemurs (lemur catta and propithecus verreauxi) at beza mahafaly special reserve, madagascar.	chemical deterioration of teeth is common among modern humans, and has been suggested for some extinct primates. dental erosion caused by acidic foods may also obscure microwear signals of mechanical food properties. ring-tailed lemurs at the beza mahafaly special reserve (bmsr), madagascar, display frequent severe tooth wear and subsequent tooth loss. in contrast, sympatric verreaux's sifaka display far less tooth wear and infrequent tooth loss, despite both species regularly consuming acidic t ...	2008	18157845
the relationship between female rank and reproductive parameters of the ringtailed lemur: a preliminary analysis.	we used data from a 13-year field study of wild ringtailed lemurs to analyze the relationship between female rank and reproductive parameters. in medium and small groups there were no significant differences in birth rate, infant mortality rate, and the number of surviving infants between the female rank categories. on the other hand, in large sized groups low-ranked females had a smaller number of surviving infants than middle-ranked females. this suggests that in large sized groups, within-gro ...	2008	18157684
a comparative analysis of serial ordering in ring-tailed lemurs (lemur catta).	research over the last 25 years has demonstrated that animals are able to organize sequences in memory and retrieve ordered sequences without language. qualitative differences have been found between the serial organization of behavior in pigeons and monkeys. here the authors test serial ordering abilities in ring-tailed lemurs, a strepsirrhine primate whose ancestral lineage diverged from that of monkeys, apes, and humans approximately 63 million years ago. lemurs' accuracy and response times w ...	2007	18085919
new hand bones of hadropithecus stenognathus: implications for the paleobiology of the archaeolemuridae.	a partial, associated skeleton of hadropithecus stenognathus (aha-i) was discovered in 2003 at andrahomana cave in southeastern madagascar. among the postcranial elements found were the first hand bones (right scaphoid, right hamate, left first metacarpal, and right and left fifth metacarpals) attributed to this rare subfossil lemur. these hand bones were compared to those of extant strepsirrhines and catarrhines in order to infer the positional adaptations of hadropithecus, and they were compar ...	2008	18068213
external genital morphology of the ring-tailed lemur (lemur catta): females are naturally "masculinized".	the extravagance and diversity of external genitalia have been well characterized in male primates; however, much less is known about sex differences or variation in female form. our study represents a departure from traditional investigations of primate reproductive anatomy because we 1) focus on external rather than internal genitalia, 2) measure both male and female structures, and 3) examine a strepsirrhine rather than an anthropoid primate. the subjects for morphological study were 21 repro ...	2008	17972270
somatic variation in living, wild ring-tailed lemurs (lemur catta).	while understanding somatic variability among wild primates can provide insight into natural patterns of developmental plasticity, published data for living populations are rare. here we provide such information for two distinct wild populations of lemur catta. variants observed include microtia, athelia, and female virilization. dental variants observed include individuals with supernumerary teeth, rotated teeth, maxillary incisor agenesis, and severe malocclusion. there was a sex bias in incis ...	2008	17878733
survey and comparison of major intestinal flora in captive and wild ring-tailed lemur (lemur catta) populations.	a survey to identify the major intestinal species of aerobic bacteria, protozoa and helminths was conducted on captive and wild populations of ring-tailed lemurs (lemur catta). samples were collected from 50 captive lemurs at 11 zoological institutions in the united states. in madagascar, 98 aerobic bacteria samples and 99 parasite samples were collected from eight sites chosen to cover a variety of populations across the species range. identical collection, preservation and lab techniques were ...	2008	17854057
prevention of urethral blockage following semen collection in two species of lemur, varecia variegata variegata and lemur catta.	lemurs are a diverse group of primates comprised of five families, all of which are found only on madagascar and the comoro islands. of the 60 known species, 17 are endangered and 5 of these are considered critically endangered. the effects of inbreeding on population health and viability have been well described; though negative inbreeding effects can be ameliorated through the introduction of new genetic material. introduction of new individuals into a population can be extremely challenging b ...	2007	17679512
biomedical evaluation of free-ranging ring-tailed lemurs (lemur catta) in three habitats at the beza mahafaly special reserve, madagascar.	complete physical examinations and biomedical sample collection were performed on 70 free-ranging ring-tailed lemurs (lemur catta) from three different habitats in the beza mahfaly special reserve (bmsr), in southern madagascar, to assess the impact of humans and habitat on lemur health. lemurs were chemically immobilized with ketamine and diazepam administered via blow darts for concurrent biomedical, morphometric, and behavioral studies. subsets of the animals had blood analyzed for hematology ...	2007	17679503
females do it better. individual recognition experiments reveal sexual dimorphism in lemur catta (linnaeus 1758) olfactory motivation and territorial defence.	in this paper, we aim at demonstrating individual recognition of female genital marking in lemur catta. by gas chromatography and behavioural trials we verified the occurrence of the three components of recognition systems. we showed that each female has a unique chemical signature (expression component), and males and females perceive female individuality (perception component). to verify the presence of the action component (the last component of recognition systems), we designed a bioassay ba ...	2007	17644684
body mass of wild ring-tailed lemurs in berenty reserve, madagascar, with reference to tick infestation: a preliminary analysis.	in 1999, we measured the body mass of 101 wild ring-tailed lemurs (lemur catta) inhabiting the berenty reserve, madagascar. in addition, we counted the number of ticks [haemaphysalis (rhipistoma) lemuris hoogstraal, 1953] infesting their facial skin and external auditory meatuses. for both males and females, the body mass appeared to increase until the age of 3 years. with the apparent exception of infants, there were no sexual differences in body mass. within a group, higher-ranked adult males ...	2008	17632687
spontaneous social orienting and gaze following in ringtailed lemurs (lemur catta).	both human and nonhuman primates preferentially orient toward other individuals and follow gaze in controlled environments. precisely where any animal looks during natural behavior, however, remains unknown. we used a novel telemetric gaze-tracking system to record orienting behavior of ringtailed lemurs (lemur catta) interacting with a naturalistic environment. we here provide the first evidence that ringtailed lemurs, group-living prosimian primates, preferentially gaze towards other individua ...	2008	17492318
chemical composition of scent marks in the ringtailed lemur (lemur catta): glandular differences, seasonal variation, and individual signatures.	the apocrine and sebaceous scent glands of ringtailed lemurs (lemur catta) appear to serve different social functions. in behavioral experiments, lemurs modulate their responses to scent marks based on the type of odorant, their own physiological state, the signaler's physiological state, and prior social experience. to examine variation in odorant chemistry relative to olfactory behavior, we used gas chromatography and mass spectrometry to analyze over 86 samples of glandular secretion collecte ...	2007	17488747
intraspecific variation in hair delta(13)c and delta(15)n values of ring-tailed lemurs (lemur catta) with known individual histories, behavior, and feeding ecology.	stable carbon and nitrogen isotope compositions were analyzed from hair samples of 30 sympatric ring-tailed lemurs (lemur catta) inhabiting the beza mahafaly special reserve, madagascar. all lemurs were known individuals involved in a longitudinal study, which allowed us to explore the degree to which group membership, sex, health status, and migration influenced their stable isotope compositions. the differences in delta(13)c and delta(15)n values between groups were small (<1.5 per thousand) b ...	2007	17455284
trypanosoma cruzi prevalence and epidemiologic trends in lemurs on st. catherines island, georgia.	lemurs on st. catherines island, georgia were tested for trypanosoma cruzi infection to develop a better understanding of the epizootiology of the parasite in nonhuman primates in the southeastern united states. fifty-six ring-tailed (lemur catta), blue-eyed black (eulemur macaco flavifrons), and black-and-white ruffed (varecia variegata variegata) lemurs were tested by hemoculture and serology to determine the prevalence of t. cruzi in the population. of those tested 3 (5%) were identified as c ...	2007	17436947
variation in fecal testosterone levels, inter-male aggression, dominance rank and age during mating and post-mating periods in wild adult male ring-tailed lemurs (lemur catta).	in primate species exhibiting seasonal reproduction, patterns of testosterone excretion in adult males are variable: in some species, peaks correlate with female receptivity periods and heightened male-male aggression over access to estrous females, in others, neither heightened aggression nor marked elevations in testosterone have been noted. in this study, we examined mean fecal testosterone ( f t) levels and intermale aggression in wild adult male ring-tailed lemurs residing in three groups a ...	2007	17427976
sex and seasonal differences in aggression and steroid secretion in lemur catta: are socially dominant females hormonally 'masculinized'?	female social dominance characterizes many strepsirrhine primates endemic to madagascar, but currently there is no comprehensive explanation for how or why female lemurs routinely dominate males. reconstructing the evolutionary pressures that may have shaped female dominance depends on better understanding the mechanism of inheritance, variation in trait expression, and correlating variables. indeed, relative to males, many female lemurs also display delayed puberty, size monomorphism, and 'masc ...	2007	17382329
density of muscle spindles in prosimian shoulder muscles reflects locomotor adaptation.	we examined the correlation between the density of muscle spindles in shoulder muscles and the locomotor mode in three species of prosimian primates: the slow loris (nycticebus coucang), garnett's galago (otolemur garnettii), and the ring-tailed lemur (lemur catta). the shoulder muscles (supraspinatus, infraspinatus, teres major, teres minor, and subscapularis) were embedded in celloidin and cut into transverse serial thin sections (40 microm); then, every tenth section was stained using the aza ...	2006	17361082
assessing flavivirus, lentivirus, and herpesvirus exposure in free-ranging ring-tailed lemurs in southwestern madagascar.	the ring-tailed lemur (lemur catta) is an endangered species found in southwestern madagascar, and understanding infectious disease susceptibility is an essential step towards the preservation of wild and captive lemur populations. lemurs are primates that are widely dispersed throughout the island of madagascar and may serve as hosts or reservoirs for zoonotic infections. the aim of this study was to determine the prevalence of antibodies to west nile virus (wnv), simian immunodeficiency virus ...	2007	17347392
a mixed epithelial and stromal tumor of the kidney in a ringtail lemur (lemur catta).	primary renal tumors are rare neoplasms in nonhuman primates. this report describes a mixed epithelial and stromal tumor of the kidney (mestk) in a 14.5-year-old female ringtail lemur. the well-demarcated, solid, and cystic mass was located in the pelvis of the left kidney and consisted histologically of both epithelial and mesenchymal components. the mesenchymal cells were arranged in fascicles around cysts lined by a well-differentiated epithelium. neither the mesenchymal nor the epithelial pa ...	2007	17317808
habitat use and social structure of a brown lemur hybrid population in the berenty reserve, madagascar.	the population of brown lemurs has rapidly grown since their founders were introduced to the berenty reserve. the founders consist of two species (eulemur fulvus rufus and e. collaris). to characterize the behavior of the population and to examine whether these characteristics affect population growth, i investigated the habitat use and social structure of the population of brown lemurs at berenty (berenty eulemur). behavior data were collected focusing on horizontal and vertical habitat use, ac ...	2007	17294429
coprophagy by wild ring-tailed lemurs (lemur catta) in human-disturbed locations adjacent to the beza mahafaly special reserve, madagascar.	coprophagy occurs in a number of animal species, including nonhuman primates. during the 2003-2004 dry seasons at the beza mahafaly special reserve, madagascar, we observed wild ring-tailed lemurs (lemur catta) consuming dried fecal matter from three different species. ring-tailed lemurs consumed human feces on 12 occasions, cattle feces twice, and feral dog feces once. coprophagy in this population may be a behavioral adaptation that provides animals access to energy and nutrients and may be an ...	2007	17253614
lateral bias to the leading limb in an olfactory social signal by male ring-tailed lemurs.	because ring-tailed lemurs (lemur catta) show handedness during feeding, i investigated whether they also show lateral preference in the limbs used by males during scent marking. during a bout of marking, a male alternates a variable number of shoulder rubs and arm marks. it is a complex social signal that has both olfactory and visual components and is frequently part of intrasexual agonistic interactions. i used all-occurrences behavior sampling, manually recorded all totally visible bouts, an ...	2007	17245755
female dominance and feeding priority in a prosimian primate: experimental manipulation of feeding competition.	female dominance and feeding priority are considered unique behavioral strategies in many malagasy lemuriformes, particularly lemur catta. two hypotheses have been introduced to explain these behavior patterns: 1) females are agonistically dominant over males to mitigate female-male food competition so that females can compensate for high energy demands and inefficient reproductive physiology, and 2) males defer to females when feeding as a reproductive strategy. we tested these hypotheses by co ...	2007	17154374
high faecal glucocorticoid levels predict mortality in ring-tailed lemurs (lemur catta).	glucocorticoid levels are commonly used as measures of stress in wild animal populations, but their relevance to individual fitness in a wild population has not been demonstrated. in this study i followed 93 ring-tailed lemurs (lemur catta) at berenty reserve in madagascar, collecting 1089 faecal samples from individually recognized animals, and recording their survival over a 2 year period. i evaluated faecal glucocorticoid levels as predictors of individual survival to the end of the study. an ...	2005	17148128
seroprevalence of toxoplasma gondii, sarcocystis neurona, and encephalitozoon cuniculi in three species of lemurs from st. catherines island, ga, usa.	in the current study, we determined the seroprevalence of toxoplasma gondii, sarcocystis neurona, and encephalitozoon cuniculi in three species of lemurs from st. catherines island, georgia. serum samples were tested from 52 ring-tailed lemurs (lemur catta), six blue-eyed black lemurs (eulemur macaco flavifrons), and four black and white ruffed lemurs (varecia variegata variegata) using an agglutination assay. three ring-tailed lemurs (5.8%) were positive for t. gondii (titer of 1:50); one ring- ...	2007	17052854
severe wear and tooth loss in wild ring-tailed lemurs (lemur catta): a function of feeding ecology, dental structure, and individual life history.	the ring-tailed lemurs at beza mahafaly special reserve, madagascar, exhibit a high frequency of severe wear and antemortem tooth loss. as part of a long-term study, we collected dental data on 83 living adult ring-tailed lemurs during 2003 and 2004. among these individuals, 192 teeth were scored as absent. the most frequently missing tooth position is m1 (24%). as m1 is the first tooth to erupt, its high frequency of absence (primarily a result of wear) is not remarkable. however, the remaining ...	2006	16962643
effects of three food enrichment items on the behavior of black lemurs (eulemur macaco macaco) and ringtail lemurs (lemur catta) at the henson robinson zoo, springfield, illinois.	this study tested 3 food enrichment items mentioned in a laboratory primate newsletter with 6 adult eulemur macaco and 3 adult lemur catta to examine whether the items would affect the behavior of the lemurs. the results suggest that food enrichment item 3 (a wire box filled with whole grapes, apples, or both hidden in straw hung from a branch within the enclosure) caused a significant decrease in the incidence of resting and a significant increase in the incidences of playing and grooming, with ...	2006	16956316
evolution of an intronic microsatellite polymorphism in toll-like receptor 2 among primates.	nonhuman primates express varying responses to mycobacterium tuberculosis: new world monkeys appear to be resistant to tuberculosis (tb) while old world monkeys seem to be particularly susceptible. the aim of this study was to elucidate the presence of the regulatory guanine-thymine (gt) repeat polymorphisms in intron 2 of toll-like receptor 2 (tlr2) associated with the development of tb in humans and to determine any variations in these microsatellite polymorphisms in primates. we sequenced the ...	2006	16912902
scent marking as resource defense by female lemur catta.	because ring-tailed lemurs (lemur catta) are a female-dominant, female-philopatric species in which the females provide the majority of parental care and troop defense, resource defense is a possible function of female lemur scent marking. to test this hypothesis, i conducted three studies. first, i presented captive, individually housed females with a series of samples of female scent, each from a different female, to determine whether they would respond to those samples and discriminate betwee ...	2006	16715509
olfactory signals and the mhc: a review and a case study in lemur catta.	the major histocompatibility complex (mhc) is the most polymorphic genetic system known in vertebrates. decades of research demonstrate that it plays a critical role in immune response and disease resistance. it has also been suggested that mhc genes influence social behavior and reproductive phenomena. studies in laboratory mice and rats report that kin recognition and mate choice are influenced by olfactory cues determined at least in part by an individual's mhc genes. this issue has stimulate ...	2006	16715507
the value of small size: loss of forest patches and ecological thresholds in southern madagascar.	many services generated by forest ecosystems provide essential support for human well-being. however, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. we present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern madagascar. two ecosystem services dependent on the forest habitats w ...	2006	16711035
influence of group size on reproductive success of female ring-tailed lemurs: distinguishing between igfc and pfc hypotheses.	based on data obtained over a period of 11 years from female ring-tailed lemurs (lemur catta), we analyzed the correlation between group size and female reproductive parameters. the birth rate and mean number of surviving infants 1 year after birth per adult female generated an inverted u-shaped curve when plotted against group size (although not significant) and number of adult female members. infant mortality rate did not have a consistent correlation with group size and number of adult female ...	2006	16645705
beyond odor discrimination: demonstrating individual recognition by scent in lemur catta.	the current study demonstrates, for the first time, the occurrence of olfactory individual recognition in a nonhuman primate species. the empirical demonstration of recognition systems requires 1) a set of cues produced by the sender (expression component), 2) the perception of these cues by the receiver (perception component), and 3) a functional response by the receiver (action component). on the basis of this framework, we analyzed by gas chromatography 35 brachial secretions collected from 1 ...	2006	16547195
retrospective evaluation of the incidence and severity of hemosiderosis in a large captive lemur population.	significant concern has been generated about the susceptibility of captive lemurs to iron storage disease, which has led some researchers to propose husbandry changes regarding dietary iron. in the current study we sought to determine the history, severity, and prevalence of iron storage disease within a large captive lemur population. iron concentration and hemosiderin accumulation in a target organ, the liver, were assessed in necropsy specimens from 15 different species (n=153) of lemurs over ...	2006	16534809
ancient positive selection on cd155 as a possible cause for susceptibility to poliovirus infection in simians.	poliovirus is the etiological agent of poliomyelitis. from the observations that only simians are susceptible to poliovirus infection and that 37 amino acid sites (the poliovirus-binding associated [pba] sites) in the domain d1 of cd155 are involved in the binding to poliovirus, it is considered that the susceptibility to poliovirus infection evolved through amino acid substitutions that occurred at the pba sites on the ancestral branch of simians. here it is shown that positive selection has op ...	2006	16500041
cutting corners: the dynamics of turning behaviors in two primate species.	in an attempt to characterize more fully the variation in substrate reaction forces in the locomotor repertoire of primates, we recorded the forces involved in directional changes for two species. these are the first records of turning forces for vertebrate quadrupeds, much less primates. three ring-tailed lemurs and two patas monkeys performed turns of approximately 30 degrees as they crossed a force platform. the ring-tailed lemurs also turned on a horizontal branch-like support with a segment ...	2006	16481581
noninvasive telemetric gaze tracking in freely moving socially housed prosimian primates.	behavioral and neurophysiological studies strongly suggest that visual orienting reflects the integration of sensory, motor, and motivational variables. relatively little is known, however, regarding the goals that govern visual orienting of animals in their natural environments. field observations suggest that most nonhuman primates orient to features of their natural environments whose salience is dictated by the visual demands of foraging, locomotion, and social interaction. this hypothesis i ...	2006	16431130
troop fission in wild ring-tailed lemurs (lemur catta) at berenty, madagascar.	a detailed fission process in a wild ring-tailed lemur (lemur catta) troop was observed at berenty reserve, madagascar. the troop fission occurred as follows: 1) during the birth season in 2000, two adult females (mother and daughter) were evicted as a result of "targeted aggression" (i.e., intense and persistent aggressive behavior toward particular individuals). 2) two adult and three immature females in the same kin group as the evicted females spontaneously immigrated into the new group. 3) ...	2006	16419123
the evolution of cathemerality in primates and other mammals: a comparative and chronoecological approach.	non-primate mammalian activity cycles are highly variable across and within taxonomic groups. in contrast, the order primates has historically been recognized as displaying a diurnal-nocturnal dichotomy that mapped, for the most part, onto the taxonomic division between haplorhines and strepsirhines. however, it has become clear over the past two decades that activity cycles in primates are not quite so clear cut. some primate species--like many large herbivorous mammals, mustelids, microtine ro ...	2006	16415585
how prosimian primates represent tools: experiments with two lemur species (eulemur fulvus and lemur catta).	the authors examined how 2 lemur species (eulemur fulvus and lemur catta) reason about tools. experiment 1 allowed subjects to use 1 of 2 canes to retrieve an inaccessible food reward. lemurs learned to solve this problem as quickly as other primates. experiment 2 then presented subjects with novel tools differing from the originals along one featural dimension. subjects attended more to tools' sizes than to their colors and made no distinction between tools' shapes and textures. experiments 3 a ...	2005	16366773
masseter electromyography during chewing in ring-tailed lemurs (lemur catta).	we examined masseter recruitment and firing patterns during chewing in four adult ring-tailed lemurs (lemur catta), using electromyography (emg). during chewing of tougher foods, the working-side superficial masseter tends to show, on average, 1.7 times more scaled emg activity than the balancing-side superficial masseter. the working-side deep masseter exhibits, on average, 2.4 times the scaled emg activity of the balancing-side deep masseter. the relatively larger activity in the working-side ...	2006	16345068
high-resolution x-ray computed tomography scanning of primate copulatory plugs.	in this study, high-resolution computed tomography x-ray scanning was used to scan ring-tailed lemur (lemur catta) copulatory plugs. this method produced accurate measures of plug volume and surface area, but was not useful for visualizing plug internal structure. copulatory plug size was of interest because it may relate to male fertilization success. copulatory plugs form from coagulated ejaculate, and are routinely displaced in this species by the penis of a subsequent mate during copulation ...	2006	16345065
anatomy of the hand and arm in daubentonia madagascariensis : a functional and phylogenetic outlook.	the aye-aye (daubentonia madagascariensis) is easily the most enigmatic of living primates. it sports a unique combination of derived characters, including continuously growing incisors, functional claws, the largest hand of any primate and a highly modified middle finger. the specialised middle finger is no longer used in locomotion and serves as a probe-like instrument for investigating, locating and extracting xylophagous (wood-boring) larvae as well as other food items. its phalanges can be ...	2006	16230860
attacks on a wild infant ring-tailed lemur (lemur catta) by immigrant males at berenty, madagascar: interpreting infanticide by males.	an orphaned infant ring-tailed lemur (lemur catta) was attacked persistently by immigrant males and disappeared with severe wounds at berenty reserve, madagascar. prior to the attacks, two troop members disappeared. on 20 november 1998, the only resident male in troop c2b disappeared suddenly. after the disappearance, nine males from three neighboring troops approached, but only six males continued to shadow the troop. of the females, the one lactating female attacked the males the most frequent ...	2005	16229008
effects of reproductive and social variables on fecal glucocorticoid levels in a sample of adult male ring-tailed lemurs (lemur catta) at the beza mahafaly reserve, madagascar.	glucocorticoids, a group of adrenal hormones, are secreted in response to stress. in male primates, variables such as breeding seasonality, dominance hierarchy stability, and aggressive and affiliative interactions can affect glucocorticoid levels. in this study, we examined interindividual differences in mean fecal glucocorticoid (fgc) levels among males in three groups of wild ring-tailed lemurs to better understand the physiological costs of group living for males in a female-dominant species ...	2005	16163722
long-term changes in dominance ranks among ring-tailed lemurs at berenty reserve, madagascar.	a study was conducted between 1989 and 2001 to monitor changes in the dominance ranks among adult ring-tailed lemurs (lemur catta) at berenty reserve, madagascar. adult females were observed to be dominant over adult males. their rank fluctuated greatly. however, in some troops, female rank orders were fairly stable over a period of several years. in general, male ranks were more unstable than female ranks. most young females aged 3 years occupied the lowest ranks among adult females. however, s ...	2005	16142423
does female dominance facilitate feeding priority in black-and-white ruffed lemurs (varecia variegata) in southeastern madagascar?	although many malagasy lemurs are thought to be female dominant and to have female feeding priority, to date the relationship between these behaviors has been rigorously established only in lemur catta, and other ways that females might achieve feeding priority have not been examined closely. erhart and overdorff [international journal of primatology 20:927-940, 1999] suggested that one way female primates achieve feeding priority is to initiate and lead groups to food, thereby gaining access to ...	2005	15898069
external forces on the limbs of jumping lemurs at takeoff and landing.	ground reaction forces were recorded for jumps of three individuals each of lemur catta and eulemur fulvus. animals jumped back and forth between a ground-mounted force plate and a 0.5-m elevated platform, covering horizontal distances of 0.5-2 m. in total, 190 takeoffs and 263 landings were collected. animals typically jumped from a run up and into a run out, during which they gained or into which they carried horizontal impulse. correspondingly, vertical impulses dominated takeoffs and landing ...	2005	15810009
molecular and serologic evidence of tick-borne ehrlichiae in three species of lemurs from st. catherines island, georgia, usa.	in recent years, several species of ehrlichiae have been recognized as tick-borne disease agents of veterinary and medical importance. clinically normal free-ranging or previously free-ranging lemurs, including 46 ring-tailed lemurs (lemur catta), six blue-eyed black lemurs (eulemur macaco flavifrons), and four black and white ruffed lemurs (varecia variegata variegata) from st. catherines island, georgia, were tested for evidence of exposure to tick-borne ehrlichiae. all 52 adult lemurs were se ...	2004	15732591
expectations about numerical events in four lemur species (eulemur fulvus, eulemur mongoz, lemur catta and varecia rubra).	although much is known about how some primates--in particular, monkeys and apes--represent and enumerate different numbers of objects, very little is known about the numerical abilities of prosimian primates. here, we explore how four lemur species (eulemur fulvus, e. mongoz, lemur catta, and varecia rubra) represent small numbers of objects. specifically, we presented lemurs with three expectancy violation looking time experiments aimed at exploring their expectations about a simple 1+1 additio ...	2005	15729569
temporalis function in anthropoids and strepsirrhines: an emg study.	the major purpose of this study is to analyze anterior and posterior temporalis muscle force recruitment and firing patterns in various anthropoid and strepsirrhine primates. there are two specific goals for this project. first, we test the hypothesis that in addition to transversely directed muscle force, the evolution of symphyseal fusion in primates may also be linked to vertically directed balancing-side muscle force during chewing (hylander et al. [2000] am. j. phys. anthropol. 112:469-492) ...	2005	15714512
disseminated toxoplasmosis in a captive ring-tailed lemur (lemur catta).	a 3-yr-old secundiparous female ring-tailed lemur presented to the auburn university small animal clinic with signs of dyspnea, lethargy, and anorexia. the animal died before she could be examined, and a full necropsy was immediately performed. provisional necropsy findings included moderate pneumonia and hepatopathy. acute interstitial pneumonia and focal hepatocellular necrosis were confirmed histologically. lung impression smears, histopathology, electron microscopy, immunohistochemistry, and ...	2004	15357101
anogenital gland secretions of lemur catta and propithecus verreauxi coquereli: a preliminary chemical examination.	although prosimians are greatly olfaction-oriented, little is known about the specifics of how they use scent to communicate. in this preliminary study we attempted to delineate intra- and interspecific differences among the anogenital gland secretions of two lemur species (lemur catta and propithecus verreauxi coquereli) using gas chromatography-mass spectrometry (gc-ms). the results indicate that the two species are discernible through scent. furthermore, we were able to identify reproductive ...	2004	15195327
tooth loss, survival, and resource use in wild ring-tailed lemurs (lemur catta): implications for inferring conspecific care in fossil hominids.		2004	15120269
a sarcoma of bone in a ring-tailed lemur (lemur catta).		1951	14874165
the skin of primates. x. the skin of the ring-tailed lemur (lemur catta).		1962	14475446
the skin of primates. xx. development of the appendages in lemur catta and lemur fulvus.		1964	14298294
[1st isolation of toxoplasma gondii in madagascar. spontaneous and experimental toxoplasmosis in lemur catta].		1962	13979332
diurnality and cone photopigment polymorphism in strepsirrhines: examination of linkage in lemur catta.	trichromatic color vision is routine among catarrhine primates, but occurs only as a variant form of color vision in some individuals in most platyrrhine genera. this arises from a fundamental difference in the organization of x-chromosome cone opsin genes in these two lineages: catarrhines have two opsin genes specifying middle- and long-wavelength-sensitive cone pigments, while platyrrhines have only a single gene. some female platyrrhine monkeys achieve trichromacy because of a species polymo ...	2003	12923905
comparison of the efficacy and cardiorespiratory effects of medetomidine-based anesthetic protocols in ring-tailed lemurs (lemur catta).	the relative efficacies and cardiorespiratory effects of three injectable anesthetic combinations containing medetomidine were evaluated in ring-tailed lemurs (lemur catta). in addition, the direct effects of medetomidine on heart rate and blood pressure were evaluated in lemurs anesthetized with isoflurane. for injectable anesthesia, captive adult ring-tailed lemurs were anesthetized with medetomidine and ketamine (0.04-0.06 mg/kg, i.m. and 3 mg/kg, i.m., respectively), medetomidine, butorphano ...	2003	12885134
social behavior and aggression among ringtailed lemurs.		2006	12861973
food procurement and tooth use in two sympatric lemur species.	this study of two lemur species (lemur catta and propithecus v. verreauxi) in madagascar combines observations of food procurement and initial food placement in the mouth with comparisons to food toughness and external properties. food toughness was hypothesized to play a decisive role in determining food placement during ingestion. it was found that tougher foods are generally ingested on the postcanines for all foods eaten. however, when leaves and fruits are analyzed separately, food size and ...	2003	12740956
biomedical evaluation of free-ranging ring-tailed lemurs (lemur catta) in tsimanampetsotsa strict nature reserve, madagascar.	complete health assessments were performed on 20 adult ring-tailed lemurs (lemur catta), 10 males and 10 females, free ranging within the tsimanampetsotsa strict nature reserve in southwest madagascar. each animal was anesthetized using tiletamine and zolazepam, weighed, and given a thorough physical examination. blood was collected for hematology, determination of plasma total protein concentration, serum chemistry, determination of fat-soluble vitamin and trace mineral concentrations, assessme ...	2003	12723796
female dominance status and fecal corticoids in a cooperative breeder with low reproductive skew: ring-tailed lemurs (lemur catta).	many studies have shown that low dominance status within a social group is associated with elevated glucocorticoid hormone production, a common index of physiological stress. however, the reverse may be true among cooperatively breeding female mammals with high reproductive skew; that is, high dominance status is associated with elevated glucocorticoid levels. elevated glucocorticoid levels in these dominant females may be a product of their being the only breeder within a group or may result fr ...	2003	12614647
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
demographic and life-history patterns in a population of ring-tailed lemurs (lemur catta) at beza mahafaly reserve, madagascar: a 15-year perspective.	over 15 field seasons (1987-2001), we collected census and life-history data on a population of individually identified ring-tailed lemurs at the beza mahafaly reserve, madagascar. no significant difference was found in population size over the study period, though a marked decline in the population occurred following a 2-year drought. the population rebounded rapidly after the immediate postdrought period. there was nearly a complete replacement of individuals over the study period. average gro ...	2003	12541335
host range of poliovirus is restricted to simians because of a rapid sequence change of the poliovirus receptor gene during evolution.	the host range of most poliovirus (pv) strains is restricted to simians. this host range specificity is believed to be determined by the interaction between pv and its receptor molecule. to elucidate the molecular basis of this species-specific infection of pv, we cloned orthologs of the pv receptor (pvr) gene ( pvr) as well as those of pv receptor-related genes 1 and 2 ( prr1 and prr2) from various mammalian species. these three genes are widely present in mammalian genomes including those of n ...	2003	12536294
naturally occurring ehrlichia chaffeensis infection in two prosimian primate species: ring-tailed lemurs (lemur catta) and ruffed lemurs (varecia variegata).	a naturally occurring infection of ehrlichia chaffeensis in lemurs is described. dna of ehrlichia chaffeensis was identified by polymerase chain reaction in peripheral blood from six of eight clinically ill lemurs. organisms were cultured from the blood of one lemur exhibiting clinical and hematologic abnormalities similar to those of humans infected with e. chaffeensis.	2002	12498671
characterization and phylogenetic relationship of prosimian mhc class i genes.	mhc class i cdna sequences from the most divergent primate group of extant primates compared to human, the suborder strepsirrhini (prosimians), are described. the sequences are derived from the gray mouse lemur (microcebus murinus) and the ring-tailed lemur (lemur catta), which are members of the malagasy lemuriformes, as well as from the pygmy slow loris (nycticebus pygmaeus), a prosimian from east asia. the m. murinus sequences have been analyzed in detail. analysis of the expression level, g/ ...	2002	12486535
analysis of chromosome conservation in lemur catta studied by chromosome paints and bac/pac probes.	a panel of human chromosome painting probes and bacterial and p1 artificial chromosome (bac/pac) clones were used in fluorescence in situ hybridization (fish) experiments to investigate the chromosome conservation of the ring-tailed lemur (lemur catta, lca) with respect to human. whole chromosome paints specific for human chromosomes 7, 9, 11, 13, 14, 17, 18, 20, 21, and x were found to identify a single chromosome or an uninterrupted chromosomal region in lca. a large set of partial chromosome ...	2002	12474064
population and social dynamics changes in ring-tailed lemur troops at berenty, madagascar between 1989 - 1999.	in the present study, we recorded all births, immigrations, deaths, and emigrations for a population of ring-tailed lemurs at berenty reserve, madagascar, between september 1989 and august 1999. in september 1989, three troops (c, b, and t) inhabited the study area of 14.2 ha. during the 10-year period, eight troop divisions, six evictions of females, and three troop takeovers of ranges by other troops occurred in and around the study area. consequently, in august 1999, the number of troops in t ...	2002	12426464
localization of a new highly repeated dna sequence of lemur cafta (lemuridae, strepsirhini).	we have isolated and cloned an 800-bp highly repeated dna (hrdna) sequence from lemur catta (lca) and described its localization on lca chromosomes. lemur catta hrdna sequences were localized by performing fish experiments on standard and elongated metaphasic chromosomes using an lca hrdna probe (lcasat). a complex hybridization pattern was detected. a strong pericentromeric hybridization signal was observed on most lca chromosomes. chromosomes 7 and 13 were lit in pericentromeric regions, as we ...	2002	12416631
[primate foot evolution: a new approach to the old problem].	functional reasons for specific changes in mammal foot skeleton occurring in course of formation and progressive evolution of locomotion on the parasagittal extremities are formulated for the first time. the paper establishes the base of the study of highly parasagittal forms (terrestrial catarhine monkeys, man and his ancestors), that evolved in primate history much later then their counterparts in other orders. the foot of primitive primate (lemur catta) is scrutinized as a model of a primitiv ...	2002	12298178
individual distinctiveness of the contact calls of ring-tailed lemurs.		2006	12207060
dental and general health in a population of wild ring-tailed lemurs: a life history approach.	data are presented on dental and general health for seven groups of wild ring-tailed lemurs, lemur catta, from the beza mahafaly reserve, in southern madagascar. as part of a study of population demography, adults were captured, collared, and tagged, and biometric measurements, dental casts, and analyses of dental and general health were made. results indicate that patterns of dental health vary by individual, age, sex, and habitat. prime adults show more dental attrition than young adults. prim ...	2002	11815947
adaptive and phylogenetic significance of ontogenetic sequences in archaeolemur, subfossil lemur from madagascar.	among the best known of recently extinct malagasy lemurs is archaeolemur, which is represented by many hundreds of specimens. the phylogenetic affinities of this taxon are unclear, especially in light of recent preliminary analysis of ancient dna which does not support its previously accepted close relationship with the living indridae. we examined the nearly complete skeletons of two adults and one juvenile and other less complete specimens to reconstruct aspects of the ontogeny of archaeolemur ...	2001	11782109
telomere biology and cellular aging in nonhuman primate cells.	to determine how cellular aging is conserved among primates, we analyzed the replicative potential and telomere shortening in skin fibroblasts of anthropoids and prosimians. the average telomere length of the new world primates ateles geoffroyi (spider monkey) and saimiri sciureus (squirrel monkey) and the old world primates macaca mulatta (rhesus monkey), pongo pygmaeus (orangutan), and pan paniscus (pigmy chimpanzee) ranged from 4 to 16 kb. we found that telomere shortening limits the replicat ...	2002	11777339
t-cell-rich b-cell lymphoma in a ring-tailed lemur (lemur catta).	a 13-yr-old ring-tailed lemur (lemur catta) was evaluated for depression, anorexia, polyuria, and polydipsia. the lemur was in poor body condition and was anemic, hypoalbuminemic, and hyponatremic. cytologic examination of aspirates of the spleen, liver, and bone marrow and histopathologic examination of liver and bone marrow biopsies revealed a disseminated round cell tumor. after euthanasia, necropsy revealed hepatomegaly, splenomegaly, and mesenteric lymphadenomegaly. neoplastic cells were pr ...	2000	11558462
centromere emergence in evolution.	evolutionary centromere repositioning is a paradox we have recently discovered while studying the conservation of the phylogenetic chromosome ix in primates. two explanations were proposed: a conservative hypothesis assuming sequential pericentric inversions, and a more challenging assumption involving centromere emergence during evolution. the complex evolutionary history showed by chromosome ix did not allow us to clearly distinguish between these two hypotheses. here we report comparative stu ...	2001	11282974
analysis of dentition of a living wild population of ring-tailed lemurs (lemur catta) from beza mahafaly, madagascar.	detailed descriptions of the dentition of many strepsirhine primate taxa are rare, despite their importance in understanding primate evolutionary biology. while several researchers have provided detailed morphological descriptions of ring-tailed lemur dentition (e.g., schwartz and tattersall [1985] am. mus. nat. hist. anthropol. pap. 60:1-100; tattersall and schwartz [1991] am. mus. nat. hist. anthropol. pap. 69:2-18), there are few studies (e.g., eaglen [1986] am. j. phys. anthropol. 71:185-201 ...	2001	11241187
description of the gastrointestinal tract of five lemur species: propithecus tattersalli, propithecus verreauxi coquereli, varecia variegata, hapalemur griseus, and lemur catta.	the objective of this project was to better define the similarities and differences in gastrointestinal morphology present in lemur species. measurements of the gastrointestinal tract of lemurs were obtained at necropsy from the captive population at duke university primate center. measurements of body length and weight, as well as gastrointestinal length, were recorded from five prosimian species: propithecus tattersalli, propithecus verreauxi, varecia variegata, hapalemur griseus, and lemur ca ...	2000	11078027
androgen levels and female social dominance in lemur catta.	morphological and behavioural traits which improve agonistic power are subject to intrasexual selection and, at the proximate level, are influenced by circulating androgens. because intrasexual selection in mammals is more intense among males, they typically dominate females. female social dominance is therefore unexpected and, indeed, rare. ring-tailed lemurs (lemur catta) are sexually monomorphic primates in which all adult females dominate all males. the goal of our study was to test the pred ...	2000	11007329
mating season aggression and fecal testosterone levels in male ring-tailed lemurs (lemur catta).	the challenge hypothesis (j. c. wingfield, r. e. hegner, b. g. ball, and a. m. duffy, 1990, am. nat. 136, 829-846) proposes that in birds, reptiles, and fish, "the frequency or intensity of reproductive aggression as an effect of t[estosterone] is strongest in situations of social instability, such as during the formation of dominance relationships, the establishment of territorial boundaries, or challenges by a conspecific male for a territory or access to mates" (p. 833). to determine the exte ...	2000	10868488