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1.
J Zoo Wildl Med ; 52(3): 1036-1041, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34687522

RESUMO

Ten red ruffed lemurs (Varecia rubra)-two adult females and their eight offspring-were evaluated in this case series. Two adult females were diagnosed with chronic, latent toxoplasmosis based on serologic testing. The first female lemur had two successive pregnancies. The first pregnancy resulted in transplacental transmission of Toxoplasma gondii. The only surviving offspring was diagnosed with congenital toxoplasmosis based on serologic testing and compatible ophthalmic lesions. The two deceased offspring had disseminated nonsuppurative inflammation and intralesional protozoal organisms consistent with T. gondii, which was confirmed by polymerase chain reaction. The second pregnancy did not result in transplacental transmission. The second chronically infected adult female lemur had one pregnancy that resulted in a single stillborn fetus without evidence of transplacental transmission of T. gondii. Treatment with trimethoprim-sulfamethoxazole and folinic acid was administered to the first adult female and one offspring, but no treatment was given to the second adult female. All surviving lemurs had no further complications associated with toxoplasmosis. This case series demonstrates that chronic, latent infection of reproductive female red ruffed lemurs with T. gondii may result in variable outcomes: (1) transplacental transmission with disseminated fetal infection and stillbirth, (2) transplacental transmission with congenital infection and survival, or (3) lack of transplacental transmission and healthy offspring. Information gained from these cases may help guide recommendations for breeding of this critically endangered species.


Assuntos
Lemur , Lemuridae , Toxoplasma , Animais , Feminino , Gravidez , Reprodução , Natimorto/veterinária
2.
J Anat ; 239(3): 669-681, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34018180

RESUMO

The anatomy of the primate forearm is frequently investigated in terms of locomotor mode, substrate use, and manual dexterity. Such studies typically rely upon broad, interspecific samples for which one or two representative taxa are used to characterize the anatomy of their genus or family. To interpret variation between distantly related taxa, however, it is necessary to contextualize these differences by quantifying variation at lower hierarchical levels, that is, more fine-grained representation within specific genera or families. In this study, we present a focused evaluation of the variation in muscle organization, integration, and architecture within two speciose primate families: the Callitrichidae and Lemuridae. We demonstrate that, within each lineage, several muscle functional groups exhibit substantial variation in muscle organization. Most notably, the digital extensors appear highly variable (particularly among callitrichids), with many unique configurations represented. In terms of architectural variables, both families are more conservative, with the exception of the genus Callimico-for which an increase is observed in forearm muscle mass and strength. We suggest this reflects the increased use of vertical climbing and trunk-to-trunk leaping within this genus relative to the more typically fine-branch substrate use of the other callitrichids. Overall, these data emphasize the underappreciated variation in forearm myology and suggest that overly generalized typification of a taxon's anatomy may conceal significant intraspecific and intrageneric variation therein. Thus, considerations of adaptation within the forearm musculature should endeavor to consider the full range of anatomical variation when making comparisons between multiple taxa within an evolutionary context.


Assuntos
Evolução Biológica , Callitrichinae/anatomia & histologia , Antebraço/anatomia & histologia , Lemuridae/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Animais , Locomoção/fisiologia
3.
Proc Biol Sci ; 288(1948): 20210346, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33849315

RESUMO

Bitter taste facilitates the detection of potentially harmful substances and is perceived via bitter taste receptors (TAS2Rs) expressed on the tongue and oral cavity in vertebrates. In primates, TAS2R16 specifically recognizes ß-glucosides, which are important in cyanogenic plants' use of cyanide as a feeding deterrent. In this study, we performed cell-based functional assays for investigating the sensitivity of TAS2R16 to ß-glucosides in three species of bamboo lemurs (Prolemur simus, Hapalemur aureus and H. griseus), which primarily consume high-cyanide bamboo. TAS2R16 receptors from bamboo lemurs had lower sensitivity to ß-glucosides, including cyanogenic glucosides, than that of the closely related ring-tailed lemur (Lemur catta). Ancestral reconstructions of TAS2R16 for the bamboo-lemur last common ancestor (LCA) and that of the Hapalemur LCA showed an intermediate sensitivity to ß-glucosides between that of the ring-tailed lemurs and bamboo lemurs. Mutagenetic analyses revealed that P. simus and H. griseus had separate species-specific substitutions that led to reduced sensitivity. These results indicate that low sensitivity to ß-glucosides at the cellular level-a potentially adaptive trait for feeding on cyanogenic bamboo-evolved independently after the Prolemur-Hapalemur split in each species.


Assuntos
Lemur , Lemuridae , Animais , Glucosídeos , Especificidade da Espécie , Paladar
4.
J Med Primatol ; 50(3): 189-192, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33860539

RESUMO

This study examines how range size affects intestinal parasite infections, and how such infections affect activity budgets in captive lemurs. There were no differences in parasite richness or intensity attributable to habitat type. However, there was a strong suggestion that parasite loads reduce activity levels.


Assuntos
Lemur , Lemuridae , Doenças Parasitárias , Animais
5.
Am J Primatol ; 83(6): e23256, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33818786

RESUMO

Arthropods (insects, spiders, etc.) can fulfill major nutritional requirements for primates, particularly in terms of proteins, fats, vitamins, and minerals. Yet, for many primate species we know very little about the frequency and importance of arthropod consumption. Traditional methods for arthropod prey identification, such as behavioral observations and fecal dissections, offer limited taxonomic resolution and, as a result, underestimate true diversity. Metabarcoding arthropod DNA from primate fecal samples provides a promising but underused alternative. Here, we inventoried arthropod prey diversity in wild lemurs by sequencing two regions of the CO1 gene. Samples were collected opportunistically from 10 species of lemurs inhabiting three national parks in southern Madagascar using a combination of focal animal follows and live trapping. In total, we detected arthropod DNA in 98 of the 170 fecal samples analyzed. Although all lemur species included in these analyses showed evidence of arthropod consumption, those within the family Cheirogaleidae appeared to consume the highest frequency and diversity of arthropods. To our knowledge, this study presents the first evidence of arthropod consumption in Phaner pallescens, Avahi peyrierasi, and Propithecus verreauxi, and identifies 32 families of arthropods as probable food items that have not been published as lemur dietary items to date. Our study emphasizes the importance of arthropods as a nutritional source and the role DNA metabarcoding can play in elucidating an animal's diet.


Assuntos
Artrópodes , Lemur , Lemuridae , Animais , Artrópodes/genética , DNA , Código de Barras de DNA Taxonômico , Madagáscar
6.
Am J Primatol ; 83(5): e23247, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33660885

RESUMO

Captive breeding is vital for primate conservation, with modern zoos serving a crucial role in breeding populations of threatened species and educating the general public. However, captive populations can experience welfare issues that may also undermine their reproductive success. To enhance the wellbeing of endangered zoo primates, we conducted a study to assess the effects of a new scent enrichment program on captive red-ruffed lemurs (Varecia rubra), black howler monkeys (Alouatta caraya), siamangs (Symphalangus syndactylus), lar gibbons (Hylobates lar) and orangutans (Pongo pygmaeus pygmaeus). We combined behavioral observations and fecal endocrinology analyses to evaluate the effects of a series of essential oils (benzoin, lavender, lemongrass) on five captive troops (N = 19) housed at Dudley Zoo & Castle and Twycross Zoo (UK). We recorded observations of natural species-specific and abnormal stress-related behaviors for 480 h using instantaneous scan sampling. We collected 189 fecal samples and measured the fecal cortisol concentrations using radioimmunoassay. We found a significant effect of the scent enrichment on behaviors, with red-ruffed lemurs and black howler monkeys reducing their social interactions, as well as red-ruffed lemurs and lar gibbons decreasing their stress-related behaviors after they were exposed to the series of essential oils. We also found that red-ruffed lemurs displayed a significant increase in fecal glucocorticoids following exposure to essential oils. Our contradictory findings suggest that the effects of this series of essential oils may change depending on the species-specific social lives and olfactory repertoires of primates. In conclusion, we cannot recommend using these essential oils widely with zoo primates without additional evaluation.


Assuntos
Lemuridae , Odorantes , Animais , Animais de Zoológico , Primatas , Olfato
7.
Folia Primatol (Basel) ; 92(1): 70-78, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33423029

RESUMO

Estimates of population size are fundamental to setting conservation priorities for threatened primate species. Many taxa in the lemur genus Lepilemur remain understudied, and basic population statistics are often dated, incomplete, or absent. Hubbard's sportive lemur (Lepilemur hubbardorum) is known only from the Zombitse-Vohibasia National Park region in southwestern Madagascar. It is listed as Endangered by the IUCN owing to its fragmented, declining habitat and limited geographic range. However, this classification has not been confirmed through systematic population estimates. To address this issue, we undertook line transect surveys in the Zombitse parcel of the National Park. We applied geospatial analyses and data to quantify forest area as a proxy for L. hubbardorumhabitat. We recorded a total of 234 L. hubbardorum sightings over 18 survey nights, representing 47.2 km of survey effort. Our surveys revealed population densities of 145.6 L. hubbardorum individuals per km2 (95% CI: 97.2-218.1), for an extrapolated abundance estimate of ca. 16,500-18,000 L. hubbardorum individuals across the protected forests of the Zombitse parcel. This abundance estimate should be considered provisional, however, because our restricted sampling area did not include the more remote regions of the National Park where habitat disturbance and hunting practices have likely contributed to localized population declines.


Assuntos
Lemuridae , Densidade Demográfica , Ecossistema , Espécies em Perigo de Extinção , Florestas , Madagáscar
8.
Am J Phys Anthropol ; 174(4): 763-775, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33463723

RESUMO

OBJECTIVES: We characterized the diet and foraging ecology of the black-and-white ruffed lemur (Varecia variegata), a specialized frugivore, and investigated behavioral strategies exhibited in response to seasonal changes in resource availability. MATERIALS AND METHODS: Behavioral data were collected from the same two adjacent communities across 29 months during two observation periods (2007-2008; 2017-2018) in Mangevo, a primary rainforest habitat in southeastern Madagascar. To analyze feeding in the context of energy maximization versus time minimization strategies, we used nonparametric tests to compare plant part constituents, dietary diversity, activity budgets, and canopy strata use between fruit-abundant versus fruit-lean seasons. RESULTS: Individuals dedicated ~30% of their time to feeding year-round, mostly in the middle canopy (11-20 m). Animals fed primarily on fruits (74% of diet), but frugivory decreased and folivory increased markedly during fruit-lean seasons. Abundant season dietary diversity (98 taxa, H' = 0.71-1.37) was greater than lean season diversity (70 taxa, H' = 0.56-1.06), which coincided with less traveling, more resting, and higher canopy use-though interannual variation was observed. CONCLUSIONS: Herein, we describe behavioral and dietary patterns that are concordant with a time minimizing behavioral strategy. Black-and-white ruffed lemur diets comprised lower taxonomic diversity, fewer fruits, and more leaves during fruit-lean months. Further, shifts toward less travel, more resting, and greater use of higher canopy levels during this time were most likely for thermoregulatory benefits.


Assuntos
Dieta/veterinária , Comportamento Alimentar/fisiologia , Lemuridae/fisiologia , Animais , Antropologia Física , Ecossistema , Feminino , Frutas , Madagáscar , Masculino , Floresta Úmida , Estações do Ano
9.
Folia Primatol (Basel) ; 92(1): 12-34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33171471

RESUMO

Ranging behavior is one important strategy by which nonhuman primates obtain access to resources critical to their biological maintenance and reproductive success. As most primates live in permanent social groups, their members must balance the benefits of group living with the costs of intragroup competition for resources. However, some taxa live in more spatiotemporally flexible social groups, whose members modify patterns of association and range use as a method to mitigate these costs. Here, we describe the range use of one such taxon, the black-and-white ruffed lemur (Varecia variegata), at an undisturbed primary rain forest site in Ranomafana National Park, Madagascar, and characterize sex differences in annual home range area, overlap, and daily distances traveled. Moreover, we characterize seasonal variability in range use and ask whether ranging behaviors can be explained by either climatic or reproductive seasonality. We found that females used significantly larger home ranges than males, though sexes shared equal and moderate levels of home range overlap. Overall, range use did not vary across seasons, although within sexes, male range use varied significantly with climate. Moreover, daily path length was best predicted by day length, female reproductive state, and sex, but was unrelated to climate variables. While the patterns of range use and spatial association presented here share some similarities with "bisexually bonded" community models described for chimpanzees, we argue that ruffed lemurs best conform to a "nuclear neighborhood" community model wherein nuclear (core) groups share the highest levels of home range overlap, and where these groups cluster spatially into adjacent "neighborhoods" within the larger, communally defended territory.


Assuntos
Comportamento de Retorno ao Território Vital , Lemuridae/fisiologia , Caracteres Sexuais , Animais , Feminino , Madagáscar , Masculino , Reprodução/fisiologia , Estações do Ano , Comportamento Social , Tempo (Meteorologia)
10.
Nat Methods ; 17(10): 1052-1059, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32994566

RESUMO

Accurate tracking and analysis of animal behavior is crucial for modern systems neuroscience. However, following freely moving animals in naturalistic, three-dimensional (3D) or nocturnal environments remains a major challenge. Here, we present EthoLoop, a framework for studying the neuroethology of freely roaming animals. Combining real-time optical tracking and behavioral analysis with remote-controlled stimulus-reward boxes, this system allows direct interactions with animals in their habitat. EthoLoop continuously provides close-up views of the tracked individuals and thus allows high-resolution behavioral analysis using deep-learning methods. The behaviors detected on the fly can be automatically reinforced either by classical conditioning or by optogenetic stimulation via wirelessly controlled portable devices. Finally, by combining 3D tracking with wireless neurophysiology we demonstrate the existence of place-cell-like activity in the hippocampus of freely moving primates. Taken together, we show that the EthoLoop framework enables interactive, well-controlled and reproducible neuroethological studies in large-field naturalistic settings.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/fisiologia , Lemuridae/fisiologia , Monitorização Fisiológica/veterinária , Neurofisiologia/instrumentação , Animais , Automação , Condicionamento Operante , Camundongos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Optogenética , Tecnologia sem Fio
11.
Zoo Biol ; 39(5): 334-344, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32608534

RESUMO

For captive primates, greater provisioning of leafy greens or foliage can promote natural foraging behavior while boosting fiber intake. Recalcitrant fiber, although minimally available to endogenous metabolism, is readily fermented into nutrients by gut microbes. Whereas most primates in captivity consume fiber-limited diets and harbor imbalanced gut microbiota compared to their wild conspecifics, the importance of fiber provisioning to primate gut microbiota has predominately been studied in folivores. We, therefore, determined if commercial lettuce could be used to encourage foraging behavior and modify the gut microbiota of captive frugivores. We provisioned ruffed lemurs (Varecia rubra and V. variegata) with romaine lettuce, on top of the standard dietary fare, for 10 consecutive days. Before and across the period of lettuce supplementation, we collected observational data of animal feeding and fecal samples for microbiome analysis, determined via amplicon sequencing. The ruffed lemurs and their gut microbes responded to lettuce provisioning. In particular, younger animals readily ate lettuce and showed no decline in consumption across study days. When controlling for the effects of host species and social-group membership, lettuce consumption shifted the composition of the gut microbiome away from each lemur's own baseline, an effect that became stronger as the study progressed. In the final study days, Ruminococcaceae UCG-008 and Akkermansia, microbes typically and respectively associated with fiber metabolism and host health, were significantly enriched in the consortia of lettuce-provisioned subjects. Ultimately, the routine offering of lettuce, leafy greens, or foliage to captive frugivores may benefit animal wellbeing.


Assuntos
Ração Animal , Dieta/veterinária , Comportamento Alimentar , Microbioma Gastrointestinal , Lemuridae/fisiologia , Alface , Bem-Estar do Animal , Animais , Animais de Zoológico , Frutas
12.
Folia Primatol (Basel) ; 91(5): 463-480, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155623

RESUMO

Cathemeral primates perform significant amounts of activity during the daylight and dark portions of the 24-h cycle. Most brown lemurs have been reported to be cathemeral. A previous study reported that brown lemurs in Ankarafantsika National Park (ANP) shift their activity pattern from being cathemeral in the dry season to being diurnal in the wet season. From July 2015 to March 2016, we collected data on active behaviour of brown lemurs over 46 full-day and 33 full-night observations, distributed evenly between the dry and wet seasons. This study examined the abiotic factors that potentially allow this seasonal shift from cathemeral to diurnal activity. We analysed the effects of day length (time from sunrise to sunset), nocturnal luminosity, and climatic factors on the diurnal and nocturnal activities of the brown lemurs in ANP using generalized linear mixed models. We found that the brown lemurs were cathemeral regardless of season. Their diurnal activity increased with increasing day length and at high humidity, but decreased on days of high temperature and low lunar luminosity. Their nocturnal activity increased with decreasing day length, during bright nights, at low temperature, and at low humidity. Their diurnal and nocturnal activities decreased during heavy rainfall. These data indicate that the photoperiodic variation entrained their activity rhythm. Bright nights may provide better visibility, advantageous for the detection of predators and food, although it may increase exposure to predators. The modification of activity level with temperature variation can be a behavioural thermoregulation. The high humidity during the wet season probably reduced evaporative cooling, inducing increased body temperature and stimulating water foraging as a potential response to dehydration and active heat dissipation. Investigation on physiological responses to environmental factors is needed to fully understand cathemerality in lemurs. These findings emphasize the flexibility of diurnal and nocturnal activity level of brown lemurs according to the great seasonal variation in tropical dry forests.


Assuntos
Ritmo Circadiano , Lemuridae/fisiologia , Fotoperíodo , Tempo (Meteorologia) , Animais , Feminino , Florestas , Madagáscar , Masculino , Estações do Ano
13.
Am J Primatol ; 82(4): e23125, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32202661

RESUMO

Due to the impact of anthropogenic activities on forest extent and integrity across Madagascar, it is increasingly necessary to assess how endangered lemur populations inhabiting human-dominated forest fragments can effectively sustain themselves ecologically. Our research addresses this concern by exploring how the distribution patterns of a small population of crowned lemurs (Eulemur coronatus), occupying a degraded forest fragment at Oronjia Forest New Protected Area in northern Madagascar, are impacted by the availability of key ecological and anthropogenic factors. We hypothesize that the distribution of E. coronatus within the fragment is limited by the availability of critical ecological resources and conditions and the intensity of anthropogenic features and activities. To examine this, we used MaxEnt to develop a species distribution model using presence-only occurrence records and 10 independent background covariates detailing the site's ecological and anthropogenic aspects. The results indicate that the realized distribution patterns of E. coronatus within human-dominated forest fragments are strongly associated with sections of forest that contain sparsely and sporadically distributed resources, such as freshwater and continuous hardwood vegetation. We conclude that the distribution of E. coronatus at Oronjia is shaped by their need to maximize foraging opportunities in a degraded forest landscape where they are subject to both environmental and anthropogenic stressors.


Assuntos
Ecossistema , Florestas , Lemuridae , Distribuição Animal , Conservação dos Recursos Naturais , Água Doce , Atividades Humanas , Madagáscar
14.
J Comp Psychol ; 134(2): 241-251, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32011154

RESUMO

A total of 16 lemurs, including representatives from three species (Lemur catta, Eulemur rubriventer, and Varecia variegata), were presented with a food-seeking task in which information about the rewards location, in one of two plastic tubes, was either known or not known. We evaluated whether lemurs would first look into the tube before making a choice. This information-seeking task aimed to assess whether subjects would display memory awareness, seeking additional information when they became aware they lacked knowledge of the rewards location. We predicted lemurs would be more likely to look into the tube when they had insufficient knowledge about the rewards position. Lemurs successfully gained the reward on most trials. However, they looked on the majority of trials regardless of whether they had all the necessary information to make a correct choice. The minimal cost to looking may have resulted in checking behavior to both confirm what they already knew and gain knowledge they did not have. When the cost of looking increased (elevating the end of tube, requiring additional energy expenditure to look inside-Experiment 2), lemurs still looked into tubes on both seen and unseen trials; however, the frequency of looking increased when opaque tubes were used (where they could not see the rewards location after baiting). This could suggest they checked more when they were less sure of their knowledge state. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Conscientização , Comportamento de Busca de Informação , Lemur/fisiologia , Recompensa , Animais , Feminino , Alimentos , Lemuridae , Masculino , Especificidade da Espécie
15.
Am J Primatol ; 82(4): e23106, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32072654

RESUMO

While the drivers of primate persistence in forest fragments have been often considered at the population level, the strategies to persist in these habitats have been little investigated at the individual or group level. Considering the rapid variation of fragment characteristics over time, longitudinal data on primates living in fragmented habitats are necessary to understand the key elements for their persistence. Since translocated animals have to cope with unfamiliar areas and face unknown fluctuations in food abundance, they offer the opportunity to study the factors contributing to successful migration between fragments. Here, we illustrated the evolution of the foraging strategies of translocated collared brown lemurs (Eulemur collaris) over an 18-year period in the Mandena Conservation Zone, south-east Madagascar. Our aim was to explore the ability of these frugivorous lemurs to adjust to recently colonized fragmented forests. Although the lemurs remained mainly frugivorous throughout the study period, over the years we identified a reduction in the consumption of leaves and exotic/pioneer plant species. These adjustments were expected in frugivorous primates living in a degraded area, but we hypothesize that they may also reflect the initial need to cope with an unfamiliar environment after the translocation. Since fragmentation is often associated with the loss of large trees and native vegetation, we suggest that the availability of exotic and/or pioneer plant species can provide an easy-to-access, nonseasonal food resource and be a key factor for persistence during the initial stage of the recolonization.


Assuntos
Comportamento Apetitivo , Dieta , Ecossistema , Lemuridae/fisiologia , Animais , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Comportamento Alimentar , Florestas , Frutas , Madagáscar
16.
Am J Primatol ; 82(4): e23104, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32011761

RESUMO

Primates worldwide are faced with increasing threats making them more vulnerable to extinction. Anthropogenic disturbances, such as habitat degradation and fragmentation, are among the main concerns, and in Madagascar, these issues have become widespread. As this situation continues to worsen, we sought to understand how fragmentation affects primate distribution throughout the island. Further, because species may exhibit different sensitivity to fragmentation, we also aimed to estimate the role of functional traits in mitigating their response. We collated data from 32 large-bodied lemur species ranges, consisting of species from the families Lemuridae (five genera) and Indriidae (two genera). We fitted Generalized Linear Models to determine the role of habitat fragmentation characteristics, for example, forest cover, patch size, edge density, and landscape configuration, as well as the protected area (PA) network, on the species relative probability of presence. We then assessed how the influence of functional traits (dietary guild, home range size) mitigate the response of species to these habitat metrics. Habitat area had a strong positive effect for many species, and there were significantly negative effects of fragmentation on the distribution of many lemur species. In addition, there was a positive influence of PAs on many lemur species' distribution. Functional trait classifications showed that lemurs of all dietary guilds are negatively affected by fragmentation; however, folivore-frugivores show greater flexibility/variability in terms of habitat area and landscape complexity compared to nearly exclusive folivores and frugivores. Furthermore, species of all home range sizes showed a negative response to fragmentation, while habitat area had an increasingly positive effect as home range increased in size. Overall, the general trends for the majority of lemur species are dire and point to the need for immediate actions on a multitude of fronts, most importantly landscape-level reforestation efforts.


Assuntos
Ecossistema , Indriidae , Lemuridae , Animais , Conservação dos Recursos Naturais , Dieta , Florestas , Comportamento de Retorno ao Território Vital , Madagáscar
17.
Am J Primatol ; 82(4): e23092, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31960516

RESUMO

The rise in research investigating fragmentation and its impact on primates and other taxa reflects the growing presence of fragmented landscapes themselves. Although numerous studies report the negative effects of fragmentation on biodiversity, it is difficult to generalize responses to fragmentation for specific taxonomic groups, such as non-human primates, when studies have not employed a definitive concept of fragmentation or fragments themselves. Madagascar's high degree of fragmentation, wealth of endemic taxa, and extensive history of ecological research provide the opportunity to compare fragmentation studies across similar contexts. We conducted a literature search of peer-reviewed articles on fragmentation in Madagascar to characterize its trends. A total of 70 articles, 46 of which concentrated on lemurs, tested the impacts of fragmentation on Malagasy taxa, while additional sources conducted research in one or more fragments without testing its effects (n = 112 total, 79 on lemurs). Studies on lemurs most frequently tested fragmentation's impacts on genetics and biodiversity metrics (n = 16 and 15 studies, respectively), although health, modeling, behavioral, and cross-disciplinary techniques were also reported. Responses to fragmentation were reported for 49 lemur species, with most studies concentrated in eastern Madagascar (87%). Although there was variation in the metrics reported in studies testing the effects of fragmentation on Malagasy species, the most common measures were fragment area, isolation, or comparison to a control site. Landscape-scale approaches and examination of fragmentation per se were rarely employed. Characterizing trends of fragmentation research in Madagascar emphasizes the challenges of documenting fragmentation's effects while highlighting the benefits of research within fragmented landscapes, particularly when combined with consideration for how the matrix within human-modified landscapes may impact primate populations.


Assuntos
Ecossistema , Florestas , Lemuridae , Animais , Biodiversidade , Madagáscar
18.
Folia Primatol (Basel) ; 91(2): 96-107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31574526

RESUMO

The recognition that much biodiversity exists outside protected areas is driving research to understand how animals survive in anthropogenic landscapes. In Madagascar, cacao (Theobroma cacao) is grown under a mix of native and exotic shade trees, and this study sought to understand whether lemurs were present in these agroecosystems. Between November 2016 and March 2017, discussions with farmers, nocturnal reconnaissance surveys and camera traps were used to confirm the presence of lemurs in the Cokafa and Mangabe plantations near Ambanja, north-west Madagascar. Four species of lemur were encountered in nocturnal surveys: Mirza zaza, Phaner parienti, Microcebussp. and Cheirogaleussp. with encounter rates of 1.2, 0.4, 0.4 and 0.3 individuals/km, respectively. The presence of Lepilemur dorsalis was confirmed by camera trap. This is the first time lemurs have been studied in cacao plantations, and understanding how these threatened animals use anthropogenic landscapes is vital for their conservation.


Assuntos
Biodiversidade , Cacau , Cheirogaleidae , Conservação dos Recursos Naturais , Lemuridae , Animais , Madagáscar , Densidade Demográfica , Árvores
19.
Anat Rec (Hoboken) ; 303(2): 295-307, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31148418

RESUMO

Hapalemur sps. and Prolemur simus (bamboo lemurs, collectively) stand out from the relatively homogeneous lemurids because they are bamboo feeders and vertical clingers and leapers. This unique diet presents equally unique challenges, like its verticality, toughness, and toxicity. The bamboo lemurs share the generalized anatomy of the other lemurids, but also display some well-documented skeletal adaptations, perhaps to overcome the problems presented by their specialization. Soft-tissue adaptations, however, remain largely unexplored. Explored here are possible soft-tissue adaptations in Hapalemur griseus. We compare H. griseus with other lemurids, Propithecus, Galago, Tarsier, and a tree shrew. Based on the available anatomical and physiological data, we hypothesize that Hapalemur and Prolemur species will have differences in hindlimb morphology when compared with other lemurids. We predict that H. griseus will have more hindlimb muscle mass and will amplify muscle mass differences with increased type II muscle fibers. Relative hindlimb muscle mass in H. griseus is less than other prosimians sampled, yet relative sural muscle mass is significantly heavier (P < 0.01) in H. griseus. Results show that the soleus muscle of H. griseus has a higher amount of type II (fast) fibers in plantarflexors. These findings indicate although H. griseus shares some generalized lemurid morphology, its diet of bamboo may have pushed this generalized lemurid to an anatomical extreme. We suspect additional bamboo-specific adaptations in their anatomy and physiology will be uncovered with further examination into the anatomy of the bamboo lemurs. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc. Anat Rec, 303:295-307, 2020. © 2019 American Association for Anatomy.


Assuntos
Adaptação Fisiológica/fisiologia , Lemuridae/anatomia & histologia , Locomoção/fisiologia , Músculo Esquelético/anatomia & histologia , Animais , Dieta , Lemuridae/fisiologia , Músculo Esquelético/fisiologia , Sasa
20.
Brain Behav Evol ; 95(1): 1-14, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31821998

RESUMO

The activity of mammal jaw elevator muscles during chewing has often been described using the concept of the triplet motor pattern, in which triplet I (balancing side superficial masseter and medial pterygoid; working side posterior temporalis) is consistently activated before triplet II (working side superficial masseter and medial pterygoid; balancing side posterior temporalis), and each triplet of muscles is recruited and modulated as a unit. Here, new measures of unison, synchrony, and coordination are used to determine whether in 5 primate species (Propithecus verreauxi, Eulemur fulvus, Papio anubis, Macaca fuscata,and Pan troglodytes)muscles in the same triplet are active more in unison, are more synchronized, and are more highly coordinated than muscles in different triplets. Results show that triplet I muscle pairs are active more in unison than other muscle pairs in Eulemur, Macaca, and Papio,buttriplet muscle pairs are mostly not more tightly synchronized than non-triplet pairs. Triplet muscles are more coordinated during triplet pattern cycles than non-triplet cycles, while non-triplet muscle pairs are more coordinated during non-triplet cycles than triplet cycles. These results suggest that the central nervous system alters patterns of coordination between cycles, recruiting triplet muscles as a coordinated unit during triplet cycles but employing a different pattern of muscle coordination during non-triplet cycles. The triplet motor pattern may simplify modulation of rhythmic mastication by being one possible unit of coordination that can be recruited on a cycle-to-cycle basis.


Assuntos
Músculo Masseter/fisiologia , Mastigação/fisiologia , Atividade Motora/fisiologia , Primatas/fisiologia , Músculos Pterigoides/fisiologia , Músculo Temporal/fisiologia , Animais , Comportamento Animal/fisiologia , Eletromiografia , Indriidae , Lemuridae , Macaca fuscata , Pan troglodytes , Papio anubis , Fatores de Tempo
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