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Lemurs
Kinds of Lemurs Terms modified by Lemurs Selected AbstractsGenetic tests of the taxonomic status of the ring-tailed lemur (Lemur catta) from the high mountain zone of the Andringitra Massif, MadagascarJOURNAL OF ZOOLOGY, Issue 1 2000Anne D. Yoder Abstract A recent survey of the high-mountain zone of the Madagascar Parc National (PN) d'Andringitra revealed the presence of an apparently isolated troop of the ring-tailed lemur Lemur catta. These animals display phenotypic and ecological characteristics that are unusual for the monotypic genus Lemur, thus raising the possibility that they are members of a different undescribed species. We present analyses of two mitochondrial genes to test the hypothesis that L. catta from Andringitra should be considered a distinct species. The results indicate that taxonomic revision is not warranted under the expectations of the phylogenetic, coalescent, or biological species concepts. Rather, the genetic patterns observed among the Andringitra and lowland mitochondrial haplotypes are consistent with those expected for a single species. [source] A comparison of auditory brainstem responses and behavioral estimates of hearing sensitivity in Lemur catta and Nycticebus coucangAMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2010Marissa A. Ramsier Abstract 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 methods. Technological advances have produced a safe and cost-effective alternative,the auditory brainstem response (ABR) method, which can be utilized in field conditions, on virtually any animal species, and without subject training. Here we used the ABR and four methods of threshold determination to construct audiograms for two strepsirrhine primates: the ring-tailed lemur (Lemur catta) and slow loris (Nycticebus coucang). Next, to verify the general efficacy of the ABR method, we compared our results to published behaviorally-derived audiograms. We found that the four ABR threshold detection methods produced similar results, including relatively elevated thresholds but similarly shaped audiograms compared to those derived behaviorally. The ABR and behavioral absolute thresholds were significantly correlated, and the frequencies of best sensitivity and high-frequency limits were comparable. However, at frequencies ,2,kHz, ABR thresholds were especially elevated, resulting in decreased agreement with behavioral thresholds and, in Lemur, the ABR 10-dB range starting points were more than 2 octaves higher than the behavioral points. Finally, a comparison of ABR- and behaviorally-derived audiograms from various animal taxa demonstrates the widespread efficacy of the ABR for estimating frequency of best sensitivity, but otherwise suggests caution; factors such as stimulus properties and threshold definition affect results. We conclude that the ABR method is a promising technique for estimating primate hearing sensitivity, but that additional data are required to explore its efficacy for estimating low-frequency thresholds. Am. J. Primatol. 72:217,233, 2010. © 2009 Wiley-Liss, Inc. [source] Ontogeny and phyletic size change in living and fossil lemursAMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2010Matthew J. Ravosa Abstract Lemurs are notable for encompassing the range of body-size variation for all primates past and present,close to four orders of magnitude. Benefiting from the phylogenetic proximity of subfossil lemurs to smaller-bodied living forms, we employ allometric data from the skull to probe the ontogenetic bases of size differentiation and morphological diversity across these clades. Building upon prior pairwise comparisons between sister taxa, we performed the first clade-wide analyses of craniomandibular growth allometries in 359 specimens from 10 lemuroids and 176 specimens from 8 indrioids. Ontogenetic trajectories for extant forms were used as a criterion of subtraction to evaluate morphological variation, and putative adaptations among sister taxa. In other words, do species-level differences in skull form result from the differential extension of common patterns of relative growth? In lemuroids, a pervasive pattern of ontogenetic scaling is observed for facial dimensions in all genera, with three genera also sharing relative growth trajectories for jaw proportions (Lemur, Eulemur, Varecia). Differences in masticatory growth and form characterizing Hapalemur and fossil Pachylemur likely reflect dietary factors. Pervasive ontogenetic scaling characterizes the facial skull in extant Indri, Avahi, and Propithecus, as well as their larger, extinct sister taxa Mesopropithecus and Babakotia. Significant interspecific differences are observed in the allometry of indrioid masticatory proportions, with variation in the mechanical advantage of the jaw adductors and stress-resisting elements correlated with diet. As the growth series and adult data are largely coincidental in each clade, interspecific variation in facial form may result from selection for body-size differentiation among sister taxa. Those cases where trajectories are discordant identify potential dietary adaptations linked to variation in masticatory forces during chewing and biting. Although such dissociations highlight selection to uncouple shared ancestral growth patterns, they occur largely via transpositions and retention of primitive size-shape covariation patterns or relative growth coefficients. Am. J. Primatol. 72:161,172, 2010. © 2009 Wiley-Liss, Inc. [source] Visual acuity in the cathemeral strepsirrhine Eulemur macaco flavifronsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2009Carrie C. Veilleux Abstract 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). Acuity in two subjects, a 3-year-old male and a 16-year-old female, was assessed behaviorally using a two-alternative forced choice discrimination task. Visual stimuli consisted of high contrast square wave gratings of seven spatial frequencies. Acuity threshold was determined using a 70% correct response criterion. Results indicate a maximum visual acuity of 5.1,c/deg for the female (1718 trials) and 3.8,c/deg for the male (846 trials). These values for E. macaco are slightly lower than those reported for diurnal Lemur catta, and are generally comparable to those reported for nocturnal Microcebus murinus and Otolemur crassicaudatus. To examine ecological sources of variation in primate visual acuity, we also calculated maximum theoretical acuity for Cheirogaleus medius (2.8,c/deg) and Tarsius syrichta (8.9,c/deg) using published data on retinal ganglion cell density and eye morphology. These data suggest that visual acuity in primates may be influenced by activity pattern, diet, and phylogenetic history. In particular, the relatively high acuity of T. syrichta and Galago senegalensis suggests that visual predation may be an important selective factor favoring high visual acuity in primates. Am. J. Primatol. 71:343,352, 2009. © 2009 Wiley-Liss, Inc. [source] Gastrointestinal Morphology of the Crowned Lemur (Eulemur coronatus)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2009C. Schwitzer Summary I provide measurements of the gastrointestinal tract of a captive female Eulemur coronatus, obtained at necropsy, and describe its morphology. The small intestine, caecum and colon were short when compared with those of other lemur species. The ratio of intestine length to body length was low. Distinct sacculations were present in the caecum, but not in the colon. The results suggest that E. coronatus is able to digest a certain amount of structural polysaccharides as contained in plant cell wall. The main fermentation chamber seems to be the caecum. Its digestive morphology implies that E. coronatus relies on a diet higher in energy-rich cell contents than those of other lemur species of similar body size. [source] Responses of Redfronted Lemurs to Experimentally Modified Alarm Calls: Evidence for Urgency-Based Changes in Call StructureETHOLOGY, Issue 9 2002Claudia Fichtel Alarm calls can serve as model systems with which to study this general question. Therefore, we examined the information content of terrestrial predator alarm calls of redfronted lemurs (Eulemur fulvus rufus), group-living Malagasy primates. Redfronted lemurs give specific alarm calls only towards raptors, whereas calls given in response to terrestrial predators (woofs) are also used in other situations characterized by high arousal. Woofs may therefore have the potential to express the perceived risk of a given threat. In order to examine whether different levels of arousal are expressed in call structure, we analysed woofs given during inter-group encounters or in response to playbacks of a barking dog, assuming that animals engaged in inter-group encounters experience higher arousal than during the playbacks of dog barks. A multivariate acoustic analysis revealed that calls given during group encounters were characterized by higher frequencies than calls given in response to playbacks of dog barks. In order to examine whether this change in call structure is salient to conspecifics, we conducted playback experiments with woofs, modified in either amplitude or frequencies. Playbacks of calls with increased frequency or amplitude elicited a longer orienting response, suggesting that different levels of arousal are expressed in call structure and provide meaningful information for listeners. In conclusion, the results of our study indicate that the information about the sender's affective state is expressed in the structure of vocalizations. [source] Sensory ecology of prey rustling sounds: acoustical features and their classification by wild Grey Mouse LemursFUNCTIONAL ECOLOGY, Issue 1 2007H. R. GOERLITZ Summary 1Predatory mammals and birds from several phylogenetic lineages use prey rustling sounds to detect and locate prey. However, it is not known whether these rustling sounds convey information about the prey, such as its size or profitability, and whether predators use them to classify prey accordingly. 2We recorded rustling sounds of insects in Madagascar walking on natural substrate and show a clear correlation between insect mass and several acoustic parameters. 3In subsequent behavioural experiments in the field, we determined whether nocturnal animals, when foraging for insects, evaluate these parameters to classify their prey. We used field-experienced Grey Mouse Lemurs Microcebus murinus in short-term captivity. Mouse Lemurs are generally regarded as a good model for the most ancestral primate condition. They use multimodal sensorial information to find food (mainly fruit, gum, insect secretions and arthropods) in nightly forest. Acoustic cues play a role in detection of insect prey. 4When presented with two simultaneous playbacks of rustling sounds, lemurs spontaneously chose the one higher above their hearing threshold, i.e. they used the rustling sound's amplitude for classification. We were not able, despite attempts in a reinforced paradigm, to persuade lemurs to use cues other than amplitude, e.g. frequency cues, for prey discrimination. 5Our data suggests that Mouse Lemurs, when foraging for insects, use the mass,amplitude correlation of prey-generated rustling sounds to evaluate the average mass of insects and to guide their foraging decisions. [source] Ontogeny and phyletic size change in living and fossil lemursAMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2010Matthew J. Ravosa Abstract Lemurs are notable for encompassing the range of body-size variation for all primates past and present,close to four orders of magnitude. Benefiting from the phylogenetic proximity of subfossil lemurs to smaller-bodied living forms, we employ allometric data from the skull to probe the ontogenetic bases of size differentiation and morphological diversity across these clades. Building upon prior pairwise comparisons between sister taxa, we performed the first clade-wide analyses of craniomandibular growth allometries in 359 specimens from 10 lemuroids and 176 specimens from 8 indrioids. Ontogenetic trajectories for extant forms were used as a criterion of subtraction to evaluate morphological variation, and putative adaptations among sister taxa. In other words, do species-level differences in skull form result from the differential extension of common patterns of relative growth? In lemuroids, a pervasive pattern of ontogenetic scaling is observed for facial dimensions in all genera, with three genera also sharing relative growth trajectories for jaw proportions (Lemur, Eulemur, Varecia). Differences in masticatory growth and form characterizing Hapalemur and fossil Pachylemur likely reflect dietary factors. Pervasive ontogenetic scaling characterizes the facial skull in extant Indri, Avahi, and Propithecus, as well as their larger, extinct sister taxa Mesopropithecus and Babakotia. Significant interspecific differences are observed in the allometry of indrioid masticatory proportions, with variation in the mechanical advantage of the jaw adductors and stress-resisting elements correlated with diet. As the growth series and adult data are largely coincidental in each clade, interspecific variation in facial form may result from selection for body-size differentiation among sister taxa. Those cases where trajectories are discordant identify potential dietary adaptations linked to variation in masticatory forces during chewing and biting. Although such dissociations highlight selection to uncouple shared ancestral growth patterns, they occur largely via transpositions and retention of primitive size-shape covariation patterns or relative growth coefficients. Am. J. Primatol. 72:161,172, 2010. © 2009 Wiley-Liss, Inc. [source] Lemurs and kids: primate conservation awareness through children's booksAMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2009Bernardo Urbani No abstract is available for this article. [source] Coat condition of ringtailed lemurs, Lemur catta at Berenty Reserve, Madagascar: I. differences by age, sex, density and tourism, 1996,2006AMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2009Alison Jolly Abstract 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 subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999,2002 scored better coats than either 1996,1997 or 2003,2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology. Am. J. Primatol. 71:191,198, 2009. © 2008 Wiley-Liss, Inc. [source] The antiquity of Madagascar's grasslands and the rise of C4 grassy biomesJOURNAL OF BIOGEOGRAPHY, Issue 10 2008William J. Bond Abstract Aim, Grasslands and savannas, which make up > 75% of Madagascar's land area, have long been viewed as anthropogenically derived after people settled on the island c. 2 ka. We investigated this hypothesis and an alternative , that the grasslands are an insular example of the post-Miocene spread of C4 grassy biomes world-wide. Location, Madagascar, southern Africa, East Africa. Methods, We compared the number of C4 grass genera in Madagascar with that in southern and south-central African floras. If the grasslands are recent we would expect to find fewer species and genera in Madagascar relative to Africa and for these species and genera to have very wide distribution ranges in Madagascar. Secondly, we searched Madagascan floras for the presence of endemic plant species or genera restricted to grasslands. We also searched for evidence of a grassland specialist fauna with species endemic to Madagascar. Plant and animal species endemic to C4 grassy biomes would not be expected if these are of recent origin. Results, Madagascar has c. 88 C4 grass genera, including six endemic genera. Excluding African genera with only one or two species, Madagascar has 86.6% of southern Africa's and 89.4% of south-central Africa's grass genera. C4 grass species make up c. 4% of the flora of both Madagascar and southern Africa and species : genus ratios are similar (4.3 and 5.1, respectively). Turnover of grasses along geographical gradients follows similar patterns to those in South Africa, with Andropogoneae dominating in mesic biomes and Chlorideae in semi-arid grassy biomes. At least 16 monocot genera have grassland members, many of which are endemic to Madagascar. Woody species in frequently burnt savannas include both Madagascan endemics and African species. A different woody flora, mostly endemic, occurs in less frequently burnt grasslands in the central highlands, filling a similar successional niche to montane C4 grasslands in Africa. Diverse vertebrate and invertebrate lineages have grassland specialists, including many endemic to Madagascar (e.g. termites, ants, lizards, snakes, birds and mammals). Grassland use of the extinct fauna is poorly known but carbon isotope analysis indicates that a hippo, two giant tortoises and one extinct lemur ate C4 or CAM (crassulacean acid metabolism) plants. Main conclusions, The diversity of C4 grass lineages in Madagascar relative to that in Africa, and the presence of plant and animal species endemic to Madagascan grassy biomes, does not fit the view that these grasslands are anthropogenically derived. We suggest that grasslands invaded Madagascar after the late Miocene, part of the world-wide expansion of C4 grassy biomes. Madagascar provides an interesting test case for biogeographical analysis of how these novel biomes assembled, and the sources of the flora and fauna that now occupy them. A necessary part of such an analysis would be to establish the pre-settlement extent of the C4 grassy biomes. Carbon isotope analysis of soil organic matter would be a feasible method for doing this. [source] External genital morphology of the ring-tailed lemur (Lemur catta): Females are naturally "masculinized"JOURNAL OF MORPHOLOGY, Issue 4 2008Christine M. Drea Abstract 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 reproductively intact, adult ring-tailed lemurs (Lemur catta), including 10 females and 11 males, two of which (one per sex) subsequently died of natural causes and also served as specimens for gross anatomical dissection. Male external genitalia presented a typical masculine configuration, with a complex distal penile morphology. In contrast, females were unusual among mammals, presenting an enlarged, pendulous external clitoris, tunneled by the urethra. Females had a shorter anogenital distance and a larger urethral meatus than did males, but organ diameter and circumference showed no sex differences. Dissection confirmed these characterizations. Noteworthy in the male were the presence of a "levator penis" muscle and discontinuity in the corpus spongiosum along the penile shaft; noteworthy in the female were an elongated clitoral shaft and glans clitoridis. The female urethra, while incorporated within the clitoral body, was not surrounded by erectile tissue, as we detected no corpus spongiosum. The os clitoridis was 43% the length and 24% the height of the os penis. On the basis of these first detailed descriptions of strepsirrhine external genitalia (for either sex), we characterize those of the female ring-tailed lemur as moderately "masculinized." Our results highlight certain morphological similarities and differences between ring-tailed lemurs and the most male-like of female mammals, the spotted hyena (Crocuta crocuta), and call attention to a potential hormonal mechanism of "masculinization" in female lemur development. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source] Genetic tests of the taxonomic status of the ring-tailed lemur (Lemur catta) from the high mountain zone of the Andringitra Massif, MadagascarJOURNAL OF ZOOLOGY, Issue 1 2000Anne D. Yoder Abstract A recent survey of the high-mountain zone of the Madagascar Parc National (PN) d'Andringitra revealed the presence of an apparently isolated troop of the ring-tailed lemur Lemur catta. These animals display phenotypic and ecological characteristics that are unusual for the monotypic genus Lemur, thus raising the possibility that they are members of a different undescribed species. We present analyses of two mitochondrial genes to test the hypothesis that L. catta from Andringitra should be considered a distinct species. The results indicate that taxonomic revision is not warranted under the expectations of the phylogenetic, coalescent, or biological species concepts. Rather, the genetic patterns observed among the Andringitra and lowland mitochondrial haplotypes are consistent with those expected for a single species. [source] Isolation of sixteen autosomal loci and a sex-linked polymorphic microsatellite locus from the Milne-Edwards' sportive lemur (Lepilemur edwardsi)MOLECULAR ECOLOGY RESOURCES, Issue 1 2009M. CRAUL Abstract We isolated 21 microsatellites from the Milne-Edwards' sportive lemur, Lepilemur edwardsi. Eighteen microsatellite sequences possessed sufficient flanking DNA for primer design. Seventeen loci amplified and were found to be polymorphic displaying two to 17 alleles in 32 unrelated individuals from a population from the National Park of Ankarafantsika in northwest Madagascar. One locus (Led-12) was found to be sex linked located on the X chromosome and can be used to sex-type 40% of female L. edwardsi lemurs. These 17 loci were characterized to investigate family structure and the phylogeography of L. edwardsi. [source] Isolation of new microsatellite markers and application in four species of mouse lemurs (Microcebus sp.)MOLECULAR ECOLOGY RESOURCES, Issue 2 2003A. Hapke Abstract We report the development of 13 new microsatellite markers for mouse lemurs (Microcebus sp.). Two markers were isolated from the fat tailed dwarf lemur (Cheirogaleus medius) and 11 from the grey mouse lemur (Microcebus murinus). A total of 561 individuals from four different species of mouse lemurs was genotyped with the newly developed markers. All markers showed Mendelian inheritance in 21 families of mouse lemurs. All markers show polymorphism in several species of mouse lemurs and seven amplified in C. medius. Among these new markers are the first 10 published for M. berthae and the first 11 for M. griseorufus. [source] Even adult sex ratios in lemurs: Potential costs and benefits of subordinate males in Verreaux's sifaka (Propithecus verreauxi) in the Kirindy Forest CFPF, MadagascarAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Peter M. Kappeler Abstract Optimal group size and composition are determined by both the costs and benefits of group living for the group's members. Verreaux's sifakas (Propithecus verreauxi), a diurnal lemur, form multimale multifemale groups with the tendency toward even adult sex ratios despite a small average number of females per group. The unexpected presence of multiple adult males may be explained by tolerance of other group members if subordinate males provide benefits to the group that outweigh the costs associated with their presence. Results based on both demographic data collected over a 13-year period and behavioral observations suggest that subordinate males provide no benefits in terms of infant survival and defense against group takeover by outside males. Although groups with more males are more likely to win intergroup encounters, subordinate males do not participate in these encounters more often than expected. Subordinate males are not costly to other group members in terms of direct intragroup feeding competition, but aggression rates between dominant and immigrated subordinate males increase in the mating season. Even though subordinate males provide very few benefits to the group, they are not very costly either and thus may be tolerated by resident females and dominant males. This tolerance may help to partially explain the tendency towards their unusual adult sex ratio. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Duetting,A mechanism to strengthen pair bonds in a dispersed pair-living primate (Lepilemur edwardsi)?AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Maria G. Méndez-Cárdenas Abstract Duetting is defined as an interactively organized pair display in which one pair partner coordinates its vocalizations in time with those of the other. It is widespread among tropical birds and cohesive pair-living primates, in which it is suggested to strengthen pair bonds. We know very little about the presence and function of duetting in dispersed pair-living mammals. We studied duetting behavior in a solitary foraging, but pair-sleeping, primate, the Milne Edwards' sportive lemur, in a dry deciduous forest of north-western Madagascar. We radio-tracked six pairs throughout 1 year and recorded their sleeping sites and associations, home-range use, and vocal and behavioral interactions. Three different periods were covered (mating, pregnancy, and offspring care). Sleeping partners form long-term pair bonds, indicated by an almost exclusive pair-specific usage of sleeping sites and home-ranges across periods. We explored three functional hypothesis of duetting: mate reunion, pair reunion, and joint-territorial defense. Pairs regularly engaged in duet calling. Duetting increased significantly during the offspring care period. Duetting occurred significantly more often at feeding sites than at sleeping sites. Pair partners synchronized behavioral activities after duetting. The activity most often synchronized was locomotion. Pair partners played an equal role in duetting with no difference between sexes in starting or terminating duetting. Altogether, our results provide support for the hypothesis that in dispersed pair-living primates, duetting evolved as a mechanism to coordinate activities between pair partners dispersed in space, to strengthen pair bonds, and, perhaps, to limit infanticide and nutritional stress in lactating females. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Brief communication: Blue eyes in lemurs and humans: Same phenotype, different genetic mechanismAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Brenda J. Bradley Abstract 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 neighboring pigmentation gene OCA2. This raises the immediate question of whether blue eyes in lemurs might have a similar genetic basis. We addressed this by sequencing the homologous genetic region in the blue-eyed black lemur (Eulemur macaco flavifrons; N = 4) and the closely-related black lemur (Eulemur macaco macaco; N = 4), which has brown eyes. We then compared a 166-bp segment corresponding to and flanking the human eye-color-associated region in these lemurs, as well as other primates (human, chimpanzee, orangutan, macaque, ring-tailed lemur, mouse lemur). Aligned sequences indicated that this region is strongly conserved in both Eulemur macaco subspecies as well as the other primates (except blue-eyed humans). Therefore, it is unlikely that this regulatory segment plays a major role in eye color differences among lemurs as it does in humans. Although convergent phenotypes can sometimes come about via the same or similar genetic changes occurring independently, this does not seem to be the case here, as we have shown that the genetic basis of blue eyes in lemurs differs from that of humans. Am J Phys Anthropol, 2009. © 2009 Wiley-Liss, Inc. [source] Effects of food, proximity, and kinship on social behavior in ringtailed lemursAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Gena C. Sbeglia Abstract 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 lemur, Lemur catta, social groups (N=14) at The Duke Lemur Center in Durham, NC. In analyzing these three factors concurrently within the same system, we attempt to establish their relative power in explaining the characteristics of social relationships. Patterns of affiliation and high-intensity agonism were best explained by kinship. Proximity also explained affiliation but did not explain agonism, which varied considerably between groups. The influence of food on social interactions was highly variable between the two groups and, therefore, did not convincingly account for the social behavior patterns we observed. Finally, different intensities of agonism have different patterns and should be analyzed individually. The variation between social groups makes it difficult for us to conclude that any one factor is primarily and universally responsible for patterns of social behavior in this species. Am. J. Primatol. 72:981,991, 2010. © 2010 Wiley-Liss, Inc. [source] Variation in dental wear and tooth loss among known-aged, older ring-tailed lemurs (Lemur catta): a comparison between wild and captive individualsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Frank P. Cuozzo Abstract 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 the Beza Mahafaly Special Reserve (BMSR), Madagascar (n=6), the percentage of severe dental wear and tooth loss ranges from 6 to 50%. Among these six individuals, the oldest (19 years old) exhibits the second lowest frequency of tooth loss (14%). The majority of captive lemurs at the Indianapolis Zoo (n=7) are older than the oldest BMSR lemur, yet display significantly less overall tooth wear for 19 of 36 tooth positions, with only two individuals exhibiting antemortem tooth loss. Among the captive lemurs, only one lemur (a nearly 29 year old male) has lost more than one tooth. This individual is only missing anterior teeth, in contrast to lemurs at BMSR, where the majority of lost teeth are postcanine teeth associated with processing specific fallback foods. Postcanine teeth also show significantly more overall wear at BMSR than in the captive sample. At BMSR, degree of severe wear and tooth loss varies in same aged, older individuals, likely reflecting differences in microhabitat, and thus the availability and use of different foods. This pattern becomes apparent before "old age," as seen in individuals as young as 7 years. Among the four "older" female lemurs at BMSR, severe wear and/or tooth loss do not predict offspring survival. Am. J. Primatol. 72:1026,1037, 2010. © 2010 Wiley-Liss, Inc. [source] A comparison of auditory brainstem responses and behavioral estimates of hearing sensitivity in Lemur catta and Nycticebus coucangAMERICAN JOURNAL OF PRIMATOLOGY, Issue 3 2010Marissa A. Ramsier Abstract 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 methods. Technological advances have produced a safe and cost-effective alternative,the auditory brainstem response (ABR) method, which can be utilized in field conditions, on virtually any animal species, and without subject training. Here we used the ABR and four methods of threshold determination to construct audiograms for two strepsirrhine primates: the ring-tailed lemur (Lemur catta) and slow loris (Nycticebus coucang). Next, to verify the general efficacy of the ABR method, we compared our results to published behaviorally-derived audiograms. We found that the four ABR threshold detection methods produced similar results, including relatively elevated thresholds but similarly shaped audiograms compared to those derived behaviorally. The ABR and behavioral absolute thresholds were significantly correlated, and the frequencies of best sensitivity and high-frequency limits were comparable. However, at frequencies ,2,kHz, ABR thresholds were especially elevated, resulting in decreased agreement with behavioral thresholds and, in Lemur, the ABR 10-dB range starting points were more than 2 octaves higher than the behavioral points. Finally, a comparison of ABR- and behaviorally-derived audiograms from various animal taxa demonstrates the widespread efficacy of the ABR for estimating frequency of best sensitivity, but otherwise suggests caution; factors such as stimulus properties and threshold definition affect results. We conclude that the ABR method is a promising technique for estimating primate hearing sensitivity, but that additional data are required to explore its efficacy for estimating low-frequency thresholds. Am. J. Primatol. 72:217,233, 2010. © 2009 Wiley-Liss, Inc. [source] Leaf nest use and construction in the golden-brown mouse lemur (Microcebus ravelobensis) in the Ankarafantsika National ParkAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2010Sandra Thorén Abstract The use of leaf nests has been documented in several mouse lemur species over the last few decades, including the golden-brown mouse lemur. Nest construction, however, has only rarely been observed and detailed descriptions of this process are lacking so far. We aim to determine the relative importance of leaf nests as shelters for the golden-brown mouse lemur, and to test predictions concerning the role of thermoregulation, safety (i.e., protection of infants), and of interspecific competition with the sympatric gray mouse lemurs in regulating nest use. Finally, we intend to clarify whether and how Microcebus ravelobensis constructs the nests, and we provide physical descriptions of seven leaf nests. Nocturnal focal observations were carried out from May 2007 to January 2008 on 18 females, and sleeping sites were regularly monitored during a six-month period. Data were collected from two study sites, one with exclusive presence of M. ravelobensis, and one with co-existence of the two mouse lemur species. Sixty-five out of 379 identified daily sleeping sites were leaf nests. These represented a total of 35 different leaf nests, used by 15 out of 18 females. The relative leaf nest use differed between sites during five out of six months, but without a consistent pattern. Interspecific competition can therefore not explain leaf nest use. Leaf nest use differed seasonally and may be partly explained by thermoregulatory advantages in the site with lower minimum temperatures. Nest use was furthermore higher than expected in both sites during the rearing season that indicates the role of nests in infant protection. For the first time, we could confirm that golden-brown mouse lemurs build leaf nests themselves. Nest building lasted between 46 and 68,min, which shows that this task is time consuming and therefore probably costly. Am. J. Primatol. 72:48,55, 2010. © 2009 Wiley-Liss, Inc. [source] Laterality in semi-free-ranging black and white ruffed lemurs (Varecia variegata variegata): head-tilt correlates with hand use during feedingAMERICAN JOURNAL OF PRIMATOLOGY, Issue 12 2009Eliza L. Nelson Abstract Previous studies in human and chimpanzee infants have identified a predictive relationship between early rightward head orientation and later right hand use. Data from lemurs suggest a leftward bias in hand preference, but there are no data on head positioning. The purpose of this study was to examine the relationship between head and hand preferences in the black and white ruffed lemur (Varecia variegata variegata). Ruffed lemurs rotate the head vertically during chewing in a behavior called head-tilting. Frequency of head-tilting and bouts of unimanual hand use were measured during normal feeding in a semi-free-ranging population of lemurs. Subjects were provisioned at feeding platforms twice daily with fresh fruits, vegetables, and other food items. Sampling was spontaneous and all observations were videotaped. No group-level bias was found for head-tilting, but a left hand bias emerged for hand use. A positive relationship was found between direction of head-tilting preference and direction of hand use preference such that left head-tilts increased as left hand use increased. Furthermore, left head-tilts increased as the degree of hand preference lateralization increased. When the hand used to bring food to the mouth just before head-tilting was examined, there was a strong bias for the left hand to precede left head-tilts. For right head-tilts, however, lemurs were equally likely to use either hand before head-tilting. Overall a strong relationship was found between the left hand and left head-tilting in black and white ruffed lemurs, suggesting a common link between these behaviors. However, the direction of bias was different from that seen in human and chimpanzee studies. Additional studies on patterns of laterality would be informative for understanding how laterality has changed across the primate order and the adaptive significance of laterality in primates. Am. J. Primatol. 71:1032,1040, 2009. © 2009 Wiley-Liss, Inc. [source] Flowers Are an important food for small apes in southern SumatraAMERICAN JOURNAL OF PRIMATOLOGY, Issue 8 2009Susan Lappan Abstract Flowers are included in the diets of many primates, but are not generally regarded as making an important contribution to primate energy budgets. However, observations of a number of lemur, platyrrhine, and cercopithecine populations suggest that some flower species may function as key primate fallback foods in periods of low abundance of preferred foods (generally ripe fruits), and that flowers may be preferred foods in some cases. I report heavy reliance on flowers during some study months for a siamang (Symphalangus syndactylus) population in southern Sumatra. Siamangs at Way Canguk spent 12% of feeding time eating flowers from October 2000 to August 2002, and in 1 month flower-feeding time exceeded 40% of total feeding time. The overall availabilities of fig and nonfig fruits, flowers, and new leaves in the study area were not significant predictors of the proportion of time that siamangs spent consuming any plant part. However, flower-feeding time was highest in months when nonfig fruit-feeding time was lowest, and a switch from heavy reliance on fruit to substantial flower consumption was associated with a shift in activity patterns toward reduced energy expenditure, which is consistent with the interpretation that flowers may function as a fallback food for Way Canguk siamangs. Hydnocarpus gracilis, a plant from which siamangs only consume flowers, was the third-most-commonly consumed plant at Way Canguk (after Ficus spp. and Dracontomelon dao), and flowers from this plant were available in most months. It is possible that relatively high local availability of these important siamang plant foods is one factor promoting high siamang density in the study area. Am. J. Primatol. 71:624,635, 2009. © 2009 Wiley-Liss, Inc. [source] Visual acuity in the cathemeral strepsirrhine Eulemur macaco flavifronsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2009Carrie C. Veilleux Abstract 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). Acuity in two subjects, a 3-year-old male and a 16-year-old female, was assessed behaviorally using a two-alternative forced choice discrimination task. Visual stimuli consisted of high contrast square wave gratings of seven spatial frequencies. Acuity threshold was determined using a 70% correct response criterion. Results indicate a maximum visual acuity of 5.1,c/deg for the female (1718 trials) and 3.8,c/deg for the male (846 trials). These values for E. macaco are slightly lower than those reported for diurnal Lemur catta, and are generally comparable to those reported for nocturnal Microcebus murinus and Otolemur crassicaudatus. To examine ecological sources of variation in primate visual acuity, we also calculated maximum theoretical acuity for Cheirogaleus medius (2.8,c/deg) and Tarsius syrichta (8.9,c/deg) using published data on retinal ganglion cell density and eye morphology. These data suggest that visual acuity in primates may be influenced by activity pattern, diet, and phylogenetic history. In particular, the relatively high acuity of T. syrichta and Galago senegalensis suggests that visual predation may be an important selective factor favoring high visual acuity in primates. Am. J. Primatol. 71:343,352, 2009. © 2009 Wiley-Liss, Inc. [source] Opsin gene polymorphism predicts trichromacy in a cathemeral lemurAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2009Carrie C. Veilleux Abstract Recent research has identified polymorphic trichromacy in three diurnal strepsirrhines: Coquerel's sifaka (Propithecus coquereli), black and white ruffed lemurs (Varecia variegata), and red ruffed lemurs (V. rubra). Current hypotheses suggest that the transitions to diurnality experienced by Propithecus and Varecia were necessary precursors to their independent acquisitions of trichromacy. Accordingly, cathemeral lemurs are thought to lack the M/L opsin gene polymorphism necessary for trichromacy. In this study, the M/L opsin gene was sequenced in ten cathemeral blue-eyed black lemurs (Eulemur macaco flavifrons). This analysis identified a polymorphism identical to that of other trichromatic strepsirrhines at the critical amino acid position 285 in exon 5 of the M/L opsin gene. Thus, polymorphic trichromacy is likely present in at least one cathemeral Eulemur species, suggesting that strict diurnality is not necessary for trichromacy. The presence of trichromacy in E. m. flavifrons suggests that a re-evaluation of current hypotheses regarding the evolution of strepsirrhine trichromacy may be necessary. Although the M/L opsin polymorphism may have been independently acquired three times in the lemurid,indriid clade, the distribution of opsin alleles in lemurids and indriids may also be consistent with a common origin of trichromacy in the last common ancestor of either the lemurids or the lemurid,indriid clade. Am. J. Primatol. 71:86,90, 2009. © 2008 Wiley-Liss, Inc. [source] Life history traits and parental care in Lepilemur ruficaudatusAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2008Roland Hilgartner Abstract In this study we investigated the importance of biparental care for the evolution and/or maintenance of pair-living in red-tailed sportive lemurs (Lepilemur ruficaudatus), a nocturnal folivorous lemur. Between 2000 and 2005, we collected data on life history traits from a total of 14 radio-collared pairs of adults and their offspring in Kirindy forest, western Madagascar. Predation rate varied between years with a minimum of 0% and a maximum of 40% per year. Patterns of parental care were quantified during simultaneous focal observations of both pair-partners in 2003 and 2004. Mating activity was limited to the months of May and June, as indicated by conspicuous changes of vulval morphology and male mate guarding behavior. After a gestation length of about 5 months, which is much longer than expected for a lemur of this body mass, single infants were born in November. Lactation lasted for about 50 days. Apart from lactation, females provided infant care by warming, grooming and transporting infants orally. Infants were parked in dense vegetation while females foraged. Males were seen only rarely in proximity to infants and we found no evidence for direct infant care provided by social fathers. We conclude that the necessity of direct infant care cannot explain the evolution and/or maintenance of pair-living in Lepilemur ruficaudatus. Am. J. Primatol. 70:2,11, 2008. © 2007 Wiley-Liss, Inc. [source] Phylogenetic relationships among the Lorisoidea as indicated by craniodental morphology and mitochondrial sequence dataAMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2007Judith C. Masters Abstract The phylogeny of the Afro-Asian Lorisoidea is controversial. While postcranial data attest strongly to the monophyly of the Lorisidae, most molecular analyses portray them as paraphyletic and group the Galagidae alternately with the Asian or African lorisids. One of the problems that has bedevilled phylogenetic analysis of the group in the past is the limited number of taxa sampled for both ingroup families. We present the results of a series of phylogenetic analyses based on 635 base pairs (bp) from two mitochondrial genes (12S and 16S rRNA) with and without 36 craniodental characters, for 11 galagid and five lorisid taxa. The outgroup was the gray mouse lemur (Microcebus murinus). Analyses of the molecular data included maximum parsimony (MP), neighbor joining (NJ), maximum likelihood (ML), and Bayesian methods. The model-based analyses and the combined "molecules+morphology" analyses supported monophyly of the Lorisidae and Galagidae. The lorisids form two geographically defined clades. We find no support for the taxonomy of Galagidae as proposed recently by Groves [Primate Taxonomy, Washington, DC: Smithsonian Institution Press. 350 p, 2001]. The taxonomy of Nash et al. [International Journal of Primatology 10:57,80, 1989] is supported by the combined "molecules+morphology" analysis; however, the model-based analyses suggest that Galagoides may be an assemblage of species united by plesiomorphic craniodental characters. Am. J. Primatol. 69:6,15, 2007. © 2006 Wiley-Liss, Inc. [source] Feeding behavior of lactating brown lemur females (Eulemur fulvus) in Mayotte: influence of infant age and plant phenologyAMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2006Laurent Tarnaud Abstract Altmann [Baboon Mothers and Infants, University of Chicago Press, 1980] and Dunbar and Dunbar [Animal Behavior 36:970,980, 1988] provided a model that predicts the amount of time spent feeding by lactating baboon females, as related to infant age. Dunbar's model further suggests that food quality affects the amount of time that females devote to feeding activity, and is predictable from rainfall and temperature data. In this study the model was tested with data recorded from births of the Mayotte brown lemur from four maternal dyads (Eulemur fulvus). This study also examines the correlation between female activity budget, quantities of fresh plant matter ingested, and suckling duration using data collected from focal animal samples on the mother,infant dyads. The relationships among rainfall, food supply, and food quality were also tested. It appears that female brown lemurs do not devote more time to feeding during the infant growth period. The data show that female brown lemurs increased their food intake during the early-lactating period when the frequency of suckling is the highest, and before infants begin to eat substantial amounts of solid foods. Thus, the frequency of feeding reflects the cost of lactation better than suckling duration. Furthermore, females did not appear to select foods according to their availability or rainfall levels. I hypothesize that the lack of convergence between lemur data and baboon observations is due to differences between their respective environments and their feeding ecology. These data also indicate that the most significant lactating cost for the brown lemur occurs during the early lactation period. Am. J. Primatol. 68:1,12, 2006. © 2006 Wiley-Liss, Inc. [source] Female dominance in captive gray mouse lemurs (Microcebus murinus)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2001Ute Radespiel Abstract Female dominance or female feeding priority seem to be characteristic for many lemur species, but are rare traits in other primates and mammals in general. The nocturnal lemur species, however, are underrepresented in the quantitative studies on social dominance. The aim of this study is to investigate the pattern of intersexual dominance relationships in the gray mouse lemur (Microcebus murinus), a species that is generally thought to possess a number of ancestral lemur traits. The context, distribution, and outcome of intersexual conflicts are analyzed in four captive groups of gray mouse lemurs. Intersexual conflicts occurred in the study groups in different behavioral contexts and were mostly spatial interactions (chasing/fleeing, approach/avoidance). The majority of conflicts were decided, and were in all but one case won by females. This is the first evidence suggesting unconditional female dominance in a cheirogaleid primate. The existence of female dominance in most families of the Lemuriformes suggests it is an ancient trait that evolved in their common ancestor. Am. J. Primatol. 54:181,192, 2001. © 2001 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||