Publications

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
[1st isolation of toxoplasma gondii in madagascar. spontaneous and experimental toxoplasmosis in lemur catta].		1962	13979332
the skin of primates. xx. development of the appendages in lemur catta and lemur fulvus.		1964	14298294
the skin of primates. x. the skin of the ring-tailed lemur (lemur catta).		1962	14475446
a sarcoma of bone in a ring-tailed lemur (lemur catta).		1951	14874165
tooth loss, survival, and resource use in wild ring-tailed lemurs (lemur catta): implications for inferring conspecific care in fossil hominids.		2004	15120269
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
behavioral responses to tooth loss in wild ring-tailed lemurs (lemur catta) at the beza mahafaly special reserve, madagascar.	severe dental wear and tooth loss is often assumed to impede the processing, breakdown, and energetic conversion of food items, thereby negatively impacting individual health, reproduction, and survival. ring-tailed lemurs at the beza mahafaly special reserve demonstrate exceptionally high frequencies of severe dental wear and antemortem tooth loss, yet often survive multiple years with these impairments. to test the hypothesis that these lemurs mitigate tooth loss through behavioral adjustments ...	2009	19373842
primate phylogenomics: developing numerous nuclear non-coding, non-repetitive markers for ecological and phylogenetic applications and analysis of evolutionary rate variation.	genetic analyses are often limited by the availability of appropriate molecular markers. markers from neutrally evolving genomic regions may be particularly useful for inferring evolutionary histories because they escape the constraints of natural selection. for the majority of taxa however, obtaining such markers is challenging. advances in genomics have the potential to alleviate the shortage of neutral markers. here we present a method to develop numerous markers from putatively neutral regio ...	2009	19470178
[animal reservoirs of human virulent microsporidian species].	the main objective of the present study was to determined the occurrence of encephalitozoon intestinalis, e. hellem, e. cuniculi, and enterocytozoon bieneusi in poland in animal faecal using the fish (fluorescent in situ hybridization) and multiplex fish techniques. additional objectives included: (1) identification of animal hosts of microsporidia that are infectious to humans amongst free-ranging, captive, livestock and domestic animals; (2) a molecular analysis of randomly selected parasite i ...	2009	19579789
social complexity predicts transitive reasoning in prosimian primates.	transitive inference is a form of deductive reasoning that has been suggested as one cognitive mechanism by which animals could learn the many relationships within their group's dominance hierarchy. this process thus bears relevance to the social intelligence hypothesis which posits evolutionary links between various forms of social and nonsocial cognition. recent evidence corroborates the link between social complexity and transitive inference and indicates that highly social animals may show s ...	2008	19649139
assessment of organochlorine pesticides and metals in ring-tailed lemurs (lemur catta) at beza mahafaly special reserve, madagascar.	like most of madagascar's endemic primates, ring-tailed lemurs (lemur catta) face a number of threats to their survival. although habitat loss is of greatest concern, other anthropogenic factors including environmental contamination may also affect lemur health and survival. in this study, we examined ring-tailed lemurs from the beza mahafaly special reserve (bmsr), southern madagascar for exposure to organochlorine (oc) pesticides and metals and examined differences in contaminant concentration ...	2009	19746443
feeding outside the forest: the importance of crop raiding and an invasive weed in the diet of gallery forest ring-tailed lemurs (lemur catta) following a cyclone at the beza mahafaly special reserve, madagascar.	in january 2005, a cyclone hit southern madagascar, including the beza mahafaly special reserve, disrupting the flowering/fruiting cycle of tamarindus indica, leaving lemur catta without its major food resource during reproductive periods. we studied two adjacent groups of l. catta during the late gestation period, and both groups ventured outside the reserve to feed. the red group (rg) fed daily on cultivated sweet potato (ipomoea batatas) leaves in a nearby field, and both groups consumed leav ...	2009	19776607
seasonality, sociality, and reproduction: long-term stressors of ring-tailed lemurs (lemur catta).	fecal glucocorticoid (fgc) concentrations are reliable, non-invasive indices of physiological stress that provide insight into an animal's energetic and social demands. to better characterize the long-term stressors in adult members of a female-dominant, seasonally breeding species - the ring-tailed lemur (lemur catta) - we first validated fecal samples against serum samples and then examined the relationship between fgc concentrations and seasonal, social, demographic, genetic, and reproductive ...	2010	19804779
natural history of ehrlichia chaffeensis: vertebrate hosts and tick vectors from the united states and evidence for endemic transmission in other countries.	ehrlichia chaffeensis, an intracellular gram-negative zoonotic bacterium, is the causative agent of human monocytotropic ehrlichiosis (hme). in humans, the disease can range from a mild, non-specific illness with few to no clinical signs to a moderately severe to fatal disease, especially those with compromised immune systems. e. chaffeensis is maintained in a complex cycle involving white-tailed deer (wtd; odocoileus virginianus) as a primary reservoir and the lone star tick (lst; amblyomma ame ...	2010	19819631
condensed tannin intake in spiny-forest-dwelling lemur catta at berenty reserve, madagascar, during reproductive periods.	primates vary in their choice or avoidance of plant foods high in condensed tannins (ct). our study focused on ct intake in two groups of lemur catta residing in spiny forest habitat during two reproductive periods. we examined whether l. catta in this habitat avoided plant foods high in ct, and whether reproductive females ingested lower concentrations of ct compared with males, since ct consumption compromises protein absorption. feeding data and plant food samples were collected during reprod ...	2009	19864917
the impact of fallback foods on wild ring-tailed lemur biology: a comparison of intact and anthropogenically disturbed habitats.	fallback foods are often viewed as central in shaping primate morphology, and influencing adaptive shifts in hominin and other primate evolution. here we argue that fruit of the tamarind tree (tamarindus indica) qualifies as a fallback food of ring-tailed lemurs (lemur catta) at the beza mahafaly special reserve (bmsr), madagascar. contrary to predictions that fallback foods may select for dental and masticatory morphologies adapted to processing these foods, consumption of tamarind fruit by the ...	2009	19890872
a comparison of auditory brainstem responses and behavioral estimates of hearing sensitivity in lemur catta and nycticebus coucang.	primates depend on acoustic signals and cues to avoid predators, locate food, and share information. accordingly, the structure and function of acoustic stimuli have long been emphasized in studies of primate behavioral and cognitive ecology. yet, few studies have addressed how well primates hear such stimuli; indeed, the auditory thresholds of most primate species are unknown. this empirical void is due in part to the logistic and economic challenges attendant on traditional behavioral testing ...	2010	19938053
decoding an olfactory mechanism of kin recognition and inbreeding avoidance in a primate.	like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. as sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation. using a molecular approach that combined a ...	2009	19958525
making progress in genetic kin recognition among vertebrates.	a recent study in bmc evolutionary biology has shown that genetically similar individual ring-tailed lemurs are also more similar in their scent composition, suggesting a possible mechanism of kin recognition. theoretical and experimental studies reveal challenges ahead in achieving a true systems-level understanding of this process and its outcomes.	2010	20236486
total energy expenditure and body composition in two free-living sympatric lemurs.	evolutionary theories that account for the unusual socio-ecological traits and life history features of group-living prosimians, compared with other primates, predict behavioral and physiological mechanisms to conserve energy. low energy output and possible fattening mechanisms are expected, as either an adaptive response to drastic seasonal fluctuations of food supplies in madagascar, or persisting traits from previously nocturnal hypometabolic ancestors. free ranging ring-tailed lemurs (lemur ...	2010	20360848
evolutionary roots of motor planning: the end-state comfort effect in lemurs.	humans (homo sapiens) anticipate the consequences of their forthcoming actions. for example, they grasp objects with uncomfortable grasps to afford comfortable end positions-the end-state comfort (esc) effect. when did such sophisticated motor planning abilities emerge in evolution? we addressed this question by asking whether humans' most distant living primate relatives-lemurs-also exhibit the esc effect. we presented 6 species of lemurs (lemur catta, eulemur mongoz, eulemur coronatus, eulemur ...	2010	20476823
effects of food, proximity, and kinship on social behavior in ringtailed lemurs.	efforts to understand the variation in primate social systems and their underlying interaction patterns have focused on both intrinsic and extrinsic factors. in the socioecological model, food distribution and abundance have been argued to be the primary influences on the social behavior of primate species. we examined the relationship of food resources and two intrinsic factors-kinship and proximity-with patterns of affiliative and agonistic relationships in two semi-free ranging ringtailed lem ...	2010	20549762
taenia crassiceps cysticercosis in a ring-tailed lemur (lemur catta).	subcutaneous and intraperitoneal cysticercosis due to taenia crassiceps was diagnosed in a 5-yr-old male ring-tailed lemur (lemur catta) in the madrid zoo-aquarium (madrid, spain). under laparoscopic examination, several septated fibrous cystic structures and numerous masses of small transparent vesicles (ca. 3 mm in diameter) were observed subcutaneously and inside the peritoneal cavity. most of the structures were extirpated but, after 2 days of postsurgical intensive care, the animal died. th ...	2010	20597227
evidence for social learning in wild lemurs (lemur catta).	interest in social learning has been fueled by claims of culture in wild animals. these remain controversial because alternative explanations to social learning, such as asocial learning or ecological differences, remain difficult to refute. compared with laboratory-based research, the study of social learning in natural contexts is in its infancy. here, for the first time, we apply two new statistical methods, option-bias analysis and network-based diffusion analysis, to data from the wild, com ...	2010	20628161
smelling wrong: hormonal contraception in lemurs alters critical female odour cues.	animals, including humans, use olfaction to assess potential social and sexual partners. although hormones modulate olfactory cues, we know little about whether contraception affects semiochemical signals and, ultimately, mate choice. we examined the effects of a common contraceptive, medroxyprogesterone acetate (mpa), on the olfactory cues of female ring-tailed lemurs (lemur catta), and the behavioural response these cues generated in male conspecifics. the genital odorants of contracepted fema ...	2011	20667870
evaluation of male inter-troop transfer as a mating strategy among ring-tailed lemurs on st. catherines island, usa.	one commonly cited function of dispersal is to increase mating opportunities. in this study, i evaluated the hypothesis that male inter-troop transfer is used as a mating strategy in ring-tailed lemurs, lemur catta, on st. catherines island (sci), ga., usa. i measured male mating success and inter-troop transfer behavior across 5 years in a population consisting of 4 lemur groups on sci. data strongly supported dispersal as a successful mating strategy of natal males, because these males did not ...	2010	20720432
variation in dental wear and tooth loss among known-aged, older ring-tailed lemurs (lemur catta): a comparison between wild and captive individuals.	tooth wear is generally an age-related phenomenon, often assumed to occur at similar rates within populations of primates and other mammals, and has been suggested as a correlate of reduced offspring survival among wild lemurs. few long-term wild studies have combined detailed study of primate behavior and ecology with dental analyses. here, we present data on dental wear and tooth loss in older (>10 years old) wild and captive ring-tailed lemurs (lemur catta). among older ring-tailed lemurs at ...	2010	20872788
endocrine correlates of pregnancy in the ring-tailed lemur (lemur catta): implications for the masculinization of daughters.	female ring-tailed lemurs (lemur catta) are malagasy primates that are size monomorphic with males, socially dominate males, and exhibit a long, pendulous clitoris, channeled by the urethra. these masculine traits evoke certain attributes of female spotted hyenas (crocuta crocuta) and draw attention to the potential role of androgens in lemur sexual differentiation. here, hormonal correlates of prenatal development were assessed to explore the possibility that maternal androgens may shape the ma ...	2011	20932838
lemurs in a complex landscape: mapping species density in subtropical dry forests of southwestern madagascar using data at multiple levels.	the study of southern dry forest lemurs has been largely restricted to small reserves; yet, the majority of the region's lemur populations reside outside protected areas. lemur catta and propithecus verreauxi occupy the same forests but have different dietary preferences. this study assessed l. catta and p. verreauxi population densities across a 3-km dry forest gradient (1,539 ha) in southern madagascar. the study was designed to allow lemur densities to be related to particular forest types. a ...	2011	20954249
unique spectrum of activity of prosimian trim5alpha against exogenous and endogenous retroviruses.	lentiviruses, the genus of retrovirus that includes hiv-1, rarely endogenize. some lemurs uniquely possess an endogenous lentivirus called psiv ("prosimian immunodeficiency virus"). thus, lemurs provide the opportunity to study the activity of host defense factors, such as trim5a, in the setting of germ line invasion. we characterized the activities of trim5a proteins from two distant lemurs against exogenous retroviruses and a chimeric psiv. trim5a from gray mouse lemur, which carries psiv in i ...	2011	21345948