Search

Very few primate species give birth to litters and build nests in which to care for them. Those that do are small-bodied, nocturnal, and solitary. Variegated lemurs are exceptional in that they bear litters in arboreal nests, yet are relatively large-bodied, day-active, and gregarious. Furthermore, they raise their young cooperatively and practice absentee parenting; non-clinging young are transported orally and periodically stashed in arboreal spots that are supportive, sheltered, and usually concealed. Following birth, infant nest and stash trees were mapped, measured, and taxonomically identified in a population of red variegated lemurs in Masoala National Park. About 40 trees were used per litter for nesting and stashing young in adjacent, non-overlapping core areas within the community. These were the largest trees in the forest, even larger than those used for feeding. Furthermore, most occur in valleys and are laced with lianas, creating sites that buffer young from predation, accidental falls, and to some degree, thermal stress. In combination, the number of nest and stash trees used per litter, their characteristics, and their geo-spatial arrangement indicate that such sites are both select and limited in the landscape, exposing the dependence of red variegated lemurs on intact forest canopies for raising non-clinging young within the context of an absentee parenting system. Nest and stash sites are in effect Varecia's extended phenotype. Logging of large trees in Madagascar's eastern rain forests is considered a major factor resulting in local extinctions of variegated lemurs because they rely heavily upon large, mature trees for fruit. However, this study suggests that removal of large trees may more directly precipitate local extinctions by impeding their ability to reproduce. Long-term survival of red variegated lemurs will depend upon efforts to end harmful timber extraction in its remaining stronghold, the Masoala Peninsula.

A new species of shrew tenrec, Microgale macpheei ,i s described from subfossil deposits in Andrahomana Cave, extreme southeastern Madagascar. This species is distinguished from all named taxa of Microgale by a variety of osteological, dental, and mensural characters. It is presumed to be the sister taxon to the extant species M. brevicaudata, which is not known to occur in southeastern Madagascar. Although the genus contains well over 20 living species, M. macpheei is the first known extinct shrew tenrec in the Quaternary fauna of Madagascar. Resume ´.—Une nouvelle espece de microgale,Microgale macpheei, trouvee dans les depots subfossiles de la grotte d'Andrahomana, dans l'extreme sud de Madagascar, est decrite. Cette espece se distingue de tous les taxons nommes dans ce genre par divers caracteres portant sur l'osteologie, la dentition et les mesures. Elle semble montrer des affinites avec l'espece actuelle M. brevicaudata qui n'est pas connue du sud-est de Madagascar. Bien que le genre soit representepar bien plus de 20 especes vivantes, la description de M. macpheei constitue la premiere e d'un microgale e dans la faune du Quaternaire de Madagascar.

Here we present information on the conservation status of ruffed lemurs (Varecia) north of the Bay of Antongil in northeastern Madagascar. Two contiguous protected areas were recently established that traverse this region via blocks of forest connected by narrow forest corridors: the Masoala National Park, which expands further to the east, and the Makira Protected Area, which expands further to the west and northwest. The two extant ruffed lemurs, Varecia variegata and V. rubra, overlapped in this region historically and, on rare occasions, hybridized. As such, land north of the Bay of Antongil is a critical part of the ruffed lemur's northern geographic range. Habitat surveys and interviews with local informants were carried out in this region to determine the extent of suitable habitat for Varecia populations, to assess the extent of human exploitation of this genus, and to obtain data on the western and northern range limits of V. rubra. Interviews indicated that there are populations of V. ...

Remains of what appears to be a single, subadult Hadropithecus stenognathus were recovered from a previously unexcavated site at Andrahomana Cave (southeastern Madagascar). Specimens found comprise isolated teeth and cranial fragments (including the frontal processes of the orbits), as well as a partial postcranial skeleton. They include the first associated fore- and hind-limb bones, confirming the hind-limb attributions made by Godfrey and co-workers in 1997, and refuting earlier attributions by Lamberton in 1937/1938. Of particular interest here are the previously unknown elements, including a sacrum, other vertebrae and ribs, some hand bones, and the distal epiphysis of a femur. We briefly discuss the functional implications of previously unknown elements. Hadropithecus displayed a combination of characters reminiscent of lemurids, others more like those of the larger-bodied Old World monkeys, and still others more like those of African apes. Yet other characteristics appear unique. Lemurid-like postcranial characteristics may be primitive for the Archaeolemuridae. Hadropithecus diverges from the Lemuridae in the direction of Archaeolemur, but more extremely so. Thus, for example, it exhibits a stronger reduction in the size of the hamulus of the hamate, greater anteroposterior compression of the femoral shaft, and greater asymmetry of the femoral condyles. Nothing in its postcranial anatomy signals a close relationship to either the Indriidae or the Palaeopropithecidae.

Since their discovery by Western explorers traveling to Madagascar in the 17th century, the ruffed lemurs have undergone numerous taxonomic revisions. During the 19th and 20th centuries, it was intermittently suggested that black-and-white and red ruffed lemurs hybridize in nature. Despite the fact that a natural hybrid zone has never been documented, this suggestion has played a large role in designating the two forms as subspecies of the single species Varecia variegata. Through a review and synthesis of historical documents, taxonomic literature, museum collections, menagerie and zoo records, recent survey work, genetic data, and vocalization data, we examine the evidence for a natural hybrid zone and suggest taxonomic revisions. Our work indicates a more extensive hybrid zone than previously suggested—but one in which hybridization is the exception rather than the rule. Furthermore, our findings warrant upgrading the black-and-white ruffed lemur and the red ruffed lemur from subspecies to ful...

Based on a year-long field study in northeastern Madagascar, I summarize annual patterns of niche use (food patch size, diet, forest height, and forest site) in two sympatric lemurs, Varecia variegata rubra and Eulemur fulvus albifrons. Furthermore, I examine intraspecific patterns of niche use according to sex, season, and reproductive stage in these two lemurs that differ in terms of energetic investment in reproduction. Lemurs as a group provide a special opportunity to test hypotheses concerning sex differences in niche use. Due to their body size monomorphism and seasonal, synchronous pattern of breeding, it is possible to directly evaluate whether sex differences in diet reflect high energetic investment in reproduction by females. Results confirm the hypothesis that intraspecific variation in niche use (e.g., sex differences, seasonal differences) would be more pronounced in V. v. rubra than in E. f. albifrons, due in large measure to the former's relatively high energetic investment in reproduction: 1a) Dietary sex differences in V. v. rubra are most pronounced during costly reproductive stages and involve acquisition of low-fiber, high-protein plant foods. Females of both species consume more seasonally available low-fiber protein (young leaves, flowers) relative to conspecific males during the hot dry season, but only in V. v. rubra females is this pattern also evident during gestation and lactation. 1b) The diets of female V. v. rubra and female E. f. albifrons are more similar to each other than are the diets of conspecific males and females in the case of V. v. rubra. This is not uniformly the case for female E. f. albifrons. This finding confirms a hypothesis put forward in Vasey ([2000] Am J Phys Anthropol 112:411–431) that energetic requirements of reproductive females drive niche separation more than do the energetic requirements of males. 1c) Both species synchronize most or all of lactation with seasonal food abundance and diversity. E. f. albifrons shows a more protracted period of synchrony, and this may contribute to its wide biogeographic distribution in Madagascar. 2) Sex differences and seasonal differences in microhabitat use reflect intraspecific patterns of thermoregulation, predator avoidance, and in the case of V. v. rubra, reproduction. One important factor selecting for body size monomorphism in lemurs appears to be the tight synchrony between lactation and periods of food abundance afforded by annual, seasonal breeding. Am J Phys Anthropol 118:169–183, 2002. © 2002 Wiley-Liss, Inc.

Niche separation was documented in a year-long study of Varecia variegata rubra and Eulemur fulvus albifrons on the Masoala Peninsula, Madagascar. Feeding trees were measured, and diet, forest height, and forest site were recorded at 5-min time points on focal animals. For time point data, multivariate and bivariate analysis of frequencies was employed to examine how niche dimensions vary between species according to sex, season, and reproductive stage. V. v. rubra feeds in larger trees than E. f. albifrons. V. v. rubra has a diet consisting mainly of fruit, whereas E. f. lbifrons has a more varied diet. V. v. ubra ranges mainly above 15 m in tree crowns, whereas E. f. albifrons ranges mainly below 15 m in a wide array of forest sites. Both species are largely frugivorous, but they harvest fruit in different-sized trees, in different quantities, and in different forest strata. Niche partitioning varies in tandem with seasonal shifts in climate and food availability and with reproductive stages. Seasonal shifts in forest site and forest height use are largely attributed to species-specific tactics for behavioral thermoregulation and predator avoidance. The diet of E. f. albifrons is diverse whether examined by season or reproductive stage. However, females of both species diversify their diets with more low-fiber protein than males during gestation, lactation, and the hot seasons. This pattern is most pronounced for V. v. rubra females and may be directly attributed to high energetic investment in reproduction. These results suggest that niche partitioning may be driven more by the energetic requirements of reproductive females than males. Am J Phys Anthropol 112:411–431, 2000. © 2000 Wiley-Liss, Inc.

I surveyed the Anaovandrano River Watershed to assess whether large tracts of primary lowland rain forest still occur there and to what extent red ruffed lemurs (Varecia variegata rubra) populate the interior of the Masoala Peninsula. These data permit an informed estimate of the remaining population size for this subspecies. I located large tracts of primary lowland rain forest in the interior, but fragmentation has begun. Red ruffed lemurs appear to be less dense in the interior than they are in remaining lowland coastal rain forest. I estimate the remaining population size to be between 29,682 and 51,115 individuals. Breeding population size is substantially smaller, probably

Subfossil fecal pellets associated with Archaeolemur cf. edwardsi skeletal material from Anjohikely Cave in north-western Madagascar were probably derived from this large extinct lemur. Pellets were photographed, measured, and dissected. One of the pellets dates to 830 ± 60 years BP. Pellets contain a wide variety of items indicative of omnivory, including fibrous fruit exocarps and seeds; bat, rodent, frog, and lizard bone; gastropod shell; and crustacean and arthropod exoskeletons—all within a matrix of comminuted vegetation. Pollen contents from inside intact pellets support other paleoecological evidence that recent feeding had taken place in wooded grassland habitat. This diet is consistent with ethnohistorical data and anatomical studies that indicate hard-object feeding in Archaeolemur. Archaeolemur may have deliberately entered caves to forage, although caves would also have offered water, abundant shade, cool conditions, cryptic sleeping sites, and refuge from predators. Cave-exploring behavior is rare in primates, but consistent with anatomical evidence that Archaeolemur was well adapted for terrestrial locomotion as well as arboreal climbing.

The current range of the red ruffed lemur (Varecia rubra) population is primarily restricted to forests of the Masoala Peninsula on the northeastern coast of Madagascar. Whereas much of the peninsula is protected as Masoala National Park, parts of the forest are at risk from anthropogenic pressures and habitat fragmentation. We sampled 32 individual red ruffed lemur from two sites: Ambatoledama (DAMA), a narrow forest corridor across an area of degraded habitat connecting larger blocks of forest in the northwestern reaches of the park, and Masiaposa (MAS) forest, a largely pristine forest on the lower western side of the peninsula. Population genetic parameters were estimated for these two populations employing 15 microsatellite loci derived from the V. variegata genome. We found that by exceeding the expected heterozygosity at mutation-drift equilibrium, the DAMA population has undergone a recent population bottleneck. Population structure analysis detected individuals harboring genotypic admixture of the DAMA genetic cluster in the MAS population, suggesting a possibility of unilateral gene flow or movement between these populations.

The red ruffed lemur, Varecia rubra, is a large-bodied, highly frugivorous lemur that gives birth to litters which are initially nested and then later transported orally to hidden, protected arboreal spots where they are periodically left unattended (e.g., Vasey, in press). A major question arises as to how a primate with such an unusual, costly reproductive pattern, involving simultaneous investment in multiple young, has become adapted to a diet that is seasonally scarce and requires relatively great foraging effort (e.g., in terms of time and/or distance traveled). To address this issue, I examine and compare the ranging patterns of female and

Captive studies have shown that ruffed lemurs (Varecia) have an unusual suite of reproductive traits combined with extremely high maternal reproductive costs. These traits include the bearing of litters, nesting of altricial young, and absentee parenting. To characterize the breeding system of this enigmatic lemur, reproductive traits must be contextualized in the wild. Here, I provide a preliminary report of mating and infant care in one community of wild red ruffed lemurs (Varecia rubra). Observations span a 15-month period covering two birth seasons and one mating season on the Masoala Peninsula, Madagascar. Factors that are not possible to replicate in captivity are reported, such as mating pattern, natality and mortality rates, the location of nests within the home range, and the structuring of infant care within a natural community. V. rubra at Andranobe have a fission-fusion, multifemale-multimale grouping pattern and a polygamous mating system. They do not mate monogamously or live strictly in family-based groups as suggested by previous workers. During the first 2 months of life, nests and infant stashing localities are situated within each mother’s respective core area, and inhabitants of each core area within the communal home range provide care for young. As part of their absentee parenting system, infants are left in concealed, protected, and supportive spots high in the canopy, while mothers travel distantly. This practice is termed ‘infant stashing’. Alloparenting appears to be an integral part of V. rubra’s overall reproductive strategy in the wild, as it was performed by all age-sex classes. Among the alloparental behaviors observed were infant guarding, co-stashing, infant transport, and allonursing. Alloparenting and absentee parenting may mitigate high maternal reproductive costs. Furthermore, V. rubra may have a breeding system in which genetic partners (i.e., mating partners) do not always correspond to infant care-providers. Combined with recently available information on the behavioral ecology of wild ruffed lemurs, this preliminary report suggests directions for in-depth studies on Varecia’s breeding system.

The papers in this issue were presented at a symposium during the 25th Annual Meeting of the American Society of Primatologists held in Oklahoma City, Oklahoma, in June 2002. This symposium brought together many of the scientists who have contributed to our knowledge of ruffed lemur ecology, behavior, and conservation in the past decade. One objective was to share and compare key findings about ruffed lemurs (Varecia) resulting from long-term field studies at various sites in Madagascar. A second objective was to cross-fertilize work being done in the wild with that being done in captivity, with the aim of advancing a common conservation mission for this critically endangered genus. Varecia is a prime candidate for synthetic assessments such as these because it has now been studied in both the northern and southern reaches of its geographic range, and has also been the focus of a captive-to-wild reinforcement project. The papers in this issue contribute to 1) the establishment of reference ranges for a suite of physiological parameters in healthy wild Varecia populations; 2) environmental enrichment aimed at preserving species-typical behaviors in captivity; 3) an understanding of how forest structure, floristic composition, and fruiting phenology in areas with differing disturbance histories correlate with the natural occurrence and abundance of Varecia; 4) primary knowledge concerning dominance relations between the sexes and group leadership in wild Varecia; and 5) primary knowledge concerning how wild Varecia, with their unusual reproductive pattern and heavy reliance on fruit, modulate their activity budgets seasonally and in tandem with reproductive stages. Am. J. Primatol. 66:1–6, 2005. © 2005 Wiley-Liss, Inc.

The activity budgets and daily activity rhythms of Varecia rubra were examined over an annual cycle according to season and reproductive stage. Given the relatively high reproductive costs and patchy food resources of this species, I predicted that V. rubra would 1) travel less and feed more during seasonal resource scarcity in an attempt to maintain energy balance, and 2) show sex differences in activity budgets due to differing reproductive investment. Contrary to the first prediction, V. rubra does not increase feeding time during seasonal food scarcity; rather, females feed for a consistent amount of time in every season, whereas males feed most during the resource-rich, hot dry season. The results are consistent with other predictions: V. rubra travels less in the resource-scarce cold rainy season, and there are some pronounced sex differences, with females feeding more and resting less than males in every season and in every reproductive stage except gestation. However, there are also some provocative similarities between the sexes when activity budgets are examined by reproductive stage. During gestation, female and male activity budgets do not differ and appear geared toward energy accumulation: both sexes feed and rest extensively and travel least during this stage. During lactation, activity budgets are geared toward high energy expenditure: both sexes travel most and in equal measure, and rest least, although it remains the case that females feed more and rest less than males. These similarities between female and male activity budgets appear related to cooperative infant care. The high energetic costs of reproduction in V. rubra females may require that they allot more time to feeding year round, and that their overall activity budget be more directly responsive to seasonal climate change, seasonal food distribution, and reproductive schedules.

The Primate Anthology: Essays on Primate Behavior, Ecology, and Conservation from Natural History. Russell L. Ciochon and Richard A. Nisbett. eds. Upper Saddle River, NJ: Prentice Hall, 1998. 246 pp.