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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.
Primates ; 62(6): 887-896, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34541622

RESUMO

Habitat fragmentation is one of the major types of anthropogenic change, though fragmented landscapes predate human intervention. At present, the Central Highlands of Madagascar are covered by extensive grasslands interspersed with small discrete forest patches of unknown antiquity. Ankafobe, an actively protected site, comprises two such fragments of 12 and 30 ha, respectively, known to harbor three lemur species and other endemic wildlife. At this location, we conducted a survey of resident Goodman's mouse lemurs, Microcebus lehilahytsara, to determine baseline behavioral and ecological conditions for this isolated population. By studying primates in forest fragments, investigators can characterize the effects of shrinking habitats and decreasing connectivity on species diversity and survival, thus providing a glimpse into the potential resilience of species in the face of anthropogenic disturbance. Investigating the behavioral ecology of Goodman's mouse lemurs across their geographic range could help us understand their metabolic and ecological flexibility and predict species long-term survival prospects. We conducted night transect walks, using capture techniques and telemetry, to track eight radio-collared individuals. Preliminary density estimates based on a limited number of sightings (n = 18) were 2.19 ind/ha, and home range assessments ranged between 0.22 and 3.67 ha. Mouse lemurs traveled an average of 425 m nightly during the 5-h tracking periods and primarily fed on fruits of the mistletoe Bakerella clavata. The finding that Goodman's mouse lemurs apparently thrive in the seasonally cold and arid forest fragments in the Central Highlands indicates that they may be among the most tolerant and adaptable lemur species in Madagascar. These results point towards an exciting research program that focuses on ecological tolerance as a mechanism for long-term species survival.


Assuntos
Cheirogaleidae , Lemur , Animais , Ecossistema , Florestas , Madagáscar
3.
Proc Biol Sci ; 288(1955): 20211204, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34284627

RESUMO

Recently expanded estimates for when humans arrived on Madagascar (up to approximately 10 000 years ago) highlight questions about the causes of the island's relatively late megafaunal extinctions (approximately 2000-500 years ago). Introduced domesticated animals could have contributed to extinctions, but the arrival times and past diets of exotic animals are poorly known. To conduct the first explicit test of the potential for competition between introduced livestock and extinct endemic megafauna in southern and western Madagascar, we generated new radiocarbon and stable carbon and nitrogen isotope data from the bone collagen of introduced ungulates (zebu cattle, ovicaprids and bushpigs, n = 66) and endemic megafauna (pygmy hippopotamuses, giant tortoises and elephant birds, n = 68), and combined these data with existing data from endemic megafauna (n = 282, including giant lemurs). Radiocarbon dates confirm that introduced and endemic herbivores briefly overlapped chronologically in this region between 1000 and 800 calibrated years before present (cal BP). Moreover, stable isotope data suggest that goats, tortoises and hippos had broadly similar diets or exploited similar habitats. These data support the potential for both direct and indirect forms of competition between introduced and endemic herbivores. We argue that competition with introduced herbivores, mediated by opportunistic hunting by humans and exacerbated by environmental change, contributed to the late extinction of endemic megafauna on Madagascar.


Assuntos
Extinção Biológica , Lemur , Animais , Ecossistema , Fósseis , Madagáscar , Mamíferos
4.
Sci Rep ; 11(1): 14196, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244546

RESUMO

Life history, brain size and energy expenditure scale with body mass in mammals but there is little conclusive evidence for a correlated evolution between life history and energy expenditure (either basal/resting or daily) independent of body mass. We addressed this question by examining the relationship between primate free-living daily energy expenditure (DEE) measured by doubly labeled water method (n = 18 species), life history variables (maximum lifespan, gestation and lactation duration, interbirth interval, litter mass, age at first reproduction), resting metabolic rate (RMR) and brain size. We also analyzed whether the hypometabolic primates of Madagascar (lemurs) make distinct energy allocation tradeoffs compared to other primates (monkeys and apes) with different life history traits and ecological constraints. None of the life-history traits correlated with DEE after controlling for body mass and phylogeny. In contrast, a regression model showed that DEE increased with increasing RMR and decreasing reproductive output (i.e., litter mass/interbirth interval) independent of body mass. Despite their low RMR and smaller brains, lemurs had an average DEE remarkably similar to that of haplorhines. The data suggest that lemurs have evolved energy strategies that maximize energy investment to survive in the unusually harsh and unpredictable environments of Madagascar at the expense of reproduction.


Assuntos
Encéfalo/fisiologia , Metabolismo Energético , Animais , Metabolismo Basal , Feminino , Haplorrinos/fisiologia , Hominidae/fisiologia , Lemur/fisiologia , Traços de História de Vida , Longevidade , Masculino , Tamanho do Órgão , Primatas , Reprodução , Especificidade da Espécie
5.
Int J Mol Sci ; 22(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064250

RESUMO

The members of the Lemur Tyrosine Kinases (LMTK1-3) subfamily constitute a group of three membrane-anchored kinases. They are known to influence a wide variety of key cellular events, often affecting cell proliferation and apoptosis. They have been discovered to be involved in cancer, in that they impact various signalling pathways that influence cell proliferation, migration, and invasiveness. Notably, in the context of genome-wide association studies, one member of the LMTK family has been identified as a candidate gene which could contribute to the development of prostate cancer. In this review, of published literature, we present evidence on the role of LMTKs in human prostate cancer and model systems, focusing on the complex network of interacting partners involved in signalling cascades that are frequently activated in prostate cancer malignancy. We speculate that the modulators of LMTK enzyme expression and activity would be of high clinical relevance for the design of innovative prostate cancer treatment.


Assuntos
Lemur/genética , Neoplasias da Próstata/genética , Proteínas Tirosina Quinases/genética , Animais , Humanos , Masculino , Transdução de Sinais/genética
6.
Am J Primatol ; 83(7): e23270, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34010491

RESUMO

Primate species face growing risks of extinction throughout the world. To better protect their populations, effective monitoring techniques are needed. The goal of this study was to evaluate the use of arboreal camera traps and occupancy modeling as conservation tools for threatened lemur species. This project aimed to (1) estimate the occupancy and detection probabilities of lemur species, (2) investigate factors potentially affecting lemur habitat use, and (3) determine whether ground or arboreal cameras are better for surveying lemur assemblages. We conducted camera trapping research in five forest fragments (total trap nights = 1770; 900 arboreal trap nights (134 photo events); 870 ground trap nights (2 photo events)) and reforestation areas (total trap nights = 608; 1 photo event) in Kianjavato, Madagascar from May to September 2019. We used arboreal trap data from fragments to estimate occupancy for five species: the red-fronted brown lemur (Eulemur rufifrons; ψ = 0.54 ± SD 0.03), Jolly's mouse lemur (Microcebus jollyae; ψ = 0.14 ± 0.17), the greater dwarf lemur (Cheirogaleus major; ψ = 0.42 ± 0.30), the red-bellied lemur (Eulemur rubriventer; ψ = 0.24 ± 0.03), and the black-and-white ruffed lemur (Varecia variegata; ψ = 0.24 ± 0.08). Tree diameter, elevation, distance to village, and canopy connectivity were important predictors of occupancy, while camera height, canopy connectivity, fragment ID, and fragment size predicted detection. Arboreal cameras recorded significantly higher species richness compared with ground cameras. We suggest expanded application of arboreal camera traps in future research, but we recommend longer trapping periods to better sample rarer species. Overall, arboreal camera trapping combined with occupancy modeling can be a highly efficient and useful approach for monitoring and predicting the occurrence of elusive lemur species and has the potential to be effective for other arboreal primates and canopy taxa across the globe.


Assuntos
Cheirogaleidae , Lemur , Animais , Ecossistema , Espécies em Perigo de Extinção , Florestas , Madagáscar
7.
Am J Primatol ; 83(6): e23255, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33792947

RESUMO

The novel coronavirus SARS-CoV-2, which in humans leads to the disease COVID-19, has caused global disruption and more than 2 million fatalities since it first emerged in late 2019. As we write, infection rates are at their highest point globally and are rising extremely rapidly in some areas due to more infectious variants. The primary target of SARS-CoV-2 is the cellular receptor angiotensin-converting enzyme-2 (ACE2). Recent sequence analyses of the ACE2 gene predict that many nonhuman primates are also likely to be highly susceptible to infection. However, the anticipated risk is not equal across the Order. Furthermore, some taxonomic groups show high ACE2 amino acid conservation, while others exhibit high variability at this locus. As an example of the latter, analyses of strepsirrhine primate ACE2 sequences to date indicate large variation among lemurs and lorises compared to other primate clades despite low sampling effort. Here, we report ACE2 gene and protein sequences for 71 individual strepsirrhines, spanning 51 species and 19 genera. Our study reinforces previous results while finding additional variability in other strepsirrhine species, and suggests several clades of lemurs have high potential susceptibility to SARS-CoV-2 infection. Troublingly, some species, including the rare and endangered aye-aye (Daubentonia madagascariensis), as well as those in the genera Avahi and Propithecus, may be at high risk. Given that lemurs are endemic to Madagascar and among the primates at highest risk of extinction globally, further understanding of the potential threat of COVID-19 to their health should be a conservation priority. All feasible actions should be taken to limit their exposure to SARS-CoV-2.


Assuntos
COVID-19/veterinária , Lemur , Lorisidae , Doenças dos Primatas/epidemiologia , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/epidemiologia , Lemur/genética , Lorisidae/genética , Doenças dos Primatas/virologia , Fatores de Risco
8.
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
9.
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
10.
Am J Primatol ; 83(6): e23259, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33792948

RESUMO

The ability to safely ascend and descend is critical to the success of arboreal animals. Nonprimate mammals typically descend supports headfirst aided by their claws, but primates must rely on grasping, and use a variety of behaviors to move down within an arboreal environment, including headfirst and tailfirst descending. This study assesses hypothesized body mass limits on vertical headfirst descent and identifies approximate support orientations and diameters at which headfirst descent is ceased in a sample of nine strepsirrhines species ranging in mass from 0.06 to 4.5 kg. Species under 1 kg, arboreal quadrupeds Cheirogaleus medius and Microcebus murinus, and slow climber Nycticebus pygmaeus, always descended supports headfirst regardless of orientation and diameter as long as a grasp could be established. Arboreal quadrupedal species above 1 kg, Daubetonia madagascariensis, Eulemur coronatus, Eulemur mongoz, Lemur catta, and Varecia variegata differed in the orientation at which they ceased using headfirst descent and the types of alternative descending behaviors they employed. Lemur catta, a highly terrestrial species, started to employ tailfirst descents at 45° and completely stopped using headfirst descent on steeper and thicker supports. Other arboreal quadrupeds, D. madagascariensis, E. coronatus, E. mongoz, and V. variegata, began using tailfirst descent at 60°. The vertical clinging and leaping species Propithecus coquereli rarely engaged in above branch quadrupedalism, and individuals were observed using tailfirst descents on supports as shallow as 15°. This study shows the ways in which mass and anatomy may constrain use of headfirst descent through arboreal environments, and the alternate strategies strepsirrhine primates employ to descend.


Assuntos
Lemur , Primatas , Animais , Locomoção
11.
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
12.
BMC Ecol Evol ; 21(1): 60, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882818

RESUMO

BACKGROUND: Lemurs once rivalled the diversity of rest of the primate order despite thier confinement to the island of Madagascar. We test the adaptive radiation model of Malagasy lemur diversity using a novel combination of phylogenetic comparative methods and geometric methods for quantifying tooth shape. RESULTS: We apply macroevolutionary model fitting approaches and disparity through time analysis to dental topography metrics associated with dietary adaptation, an aspect of mammalian ecology which appears to be closely related to diversification in many clades. Metrics were also reconstructed at internal nodes of the lemur tree and these reconstructions were combined to generate dietary classification probabilities at internal nodes using discriminant function analysis. We used these reconstructions to calculate rates of transition toward folivory per million-year intervals. Finally, lower second molar shape was reconstructed at internal nodes by modelling the change in shape of 3D meshes using squared change parsimony along the branches of the lemur tree. Our analyses of dental topography metrics do not recover an early burst in rates of change or a pattern of early partitioning of subclade disparity. However, rates of change in adaptations for folivory were highest during the Oligocene, an interval of possible forest expansion on the island. CONCLUSIONS: There was no clear phylogenetic signal of bursts of morphological evolution early in lemur history. Reconstruction of the molar morphologies corresponding to the ancestral nodes of the lemur tree suggest that this may have been driven by a shift toward defended plant resources, however. This suggests a response to the ecological opportunity offered by expanding forests, but not necessarily a classic adaptive radiation initiated by dispersal to Madagascar.


Assuntos
Lemur , Strepsirhini , Animais , Dieta , Madagáscar , Filogenia
13.
BMC Vet Res ; 17(1): 118, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712007

RESUMO

BACKGROUND: Anaplasma are obligate intracellular bacteria and aetiological agents of tick-borne diseases of both veterinary and medical interest. The genus Anaplasma comprises six species: Anaplasma marginale, Anaplasma centrale, Anaplasma ovis, Anaplasma phagocytophilum, Anaplasma bovis and Anaplasma platys. They can infect humans, carnivores, ruminants, rodents, insectivores, birds and reptiles. The aim of this study was to present the first clinical case of granulocytic anaplasmosis in a captive ring-tailed lemur in Poland. CASE PRESENTATION: A 4-year-old female lemur presented anorexia, epistaxis and tick infestation. The microscopic examination of a blood smear revealed morulae in neutrophils. Polymerase chain reaction test and sequencing of obtained PCR product confirmed infection by the GU183908 Anaplasma phagocytophilum strain. Therapeutic protocol included doxycycline (2.5 mg/kg p.o., b.i.d.) for 3 weeks and the lemur recovered within 24 h. CONCLUSIONS: This is the first report on granulocytic anaplasmosis in a ring-tailed lemur in Europe, indicating that A. phagocytophilum infection must also be considered in differential diagnosis in this animal species, especially in individuals with thrombocytopenia associated with Ixodes ricinus parasitism.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Anaplasmose/microbiologia , Lemur , Anaplasma phagocytophilum/genética , Anaplasmose/sangue , Anaplasmose/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , DNA Bacteriano , Doxiciclina/uso terapêutico , Feminino , Ixodes/microbiologia , Polônia , Infestações por Carrapato/veterinária
14.
Viruses ; 13(3)2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673677

RESUMO

Studies of viruses that coevolved with lemurs provide an opportunity to understand the basal traits of primate viruses and provide an evolutionary context for host-virus interactions. Germline integration of endogenous retroviruses (ERVs) are fossil evidence of past infections. Hence, characterization of novel ERVs provides insight into the ancient precursors of extant viruses and the evolutionary history of their hosts. Here, we report the discovery of a novel endogenous retrovirus present in the genome of a lemur, Coquerel's sifaka (Propithecus coquereli). Using next-generation sequencing, we identified and characterized the complete genome sequence of a retrovirus, named prosimian retrovirus 1 (PSRV1). Phylogenetic analyses indicate that PSRV1 is a gamma-type betaretrovirus basal to the other primate betaretroviruses and most closely related to simian retroviruses. Molecular clock analysis of PSRV1 long terminal repeat (LTR) sequences estimated the time of endogenization within 4.56 MYA (± 2.4 MYA), placing it after the divergence of Propithecus species. These results indicate that PSRV1 is an important milestone of lemur evolution during the radiation of the Propithecus genus. These findings may have implications for both human and animal health in that the acquisition of a gamma-type env gene within an endogenized betaretrovirus could facilitate a cross-species jump between vertebrate class hosts.


Assuntos
Retrovirus Endógenos/genética , Lemur/virologia , Strepsirhini/virologia , Sequência de Aminoácidos , Animais , Evolução Molecular , Genoma/genética , Humanos , Filogenia
15.
J Med Entomol ; 58(2): 983-989, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33710313

RESUMO

Madagascar is a hotspot of biodiversity, but poverty and population growth provoke a high risk of conflict between food security and biodiversity conservation in this tropical country. Numerous vector-borne diseases, including viral infections, affect public health in Madagascar and a continuous expansion of anthropogenically used areas intensifies contact on the human-wildlife interface. However, data on human and animal pathogens in potential insect vectors is limited. Therefore, we conducted a parasitological and virological survey of 785 adult female mosquitoes between March and May 2016 at the Ankarafantsika National Park in northwestern Madagascar. Screening included Alpha-, Phlebo-, and Flaviviridae and the recently described filarial nematode species, Lemurfilaria lemuris. The predominant mosquito genus was Culex (91%), followed by Mansonia (4.1%), Anopheles (3.4%), and Aedes (0.9%). Viral screening revealed no arboviruses, but an insect-specific flavivirus in two Culex sitiens pools. No pools screened positive for the lemur-specific filarial nematode L. lemuris.


Assuntos
Flavivirus/isolamento & purificação , Mosquitos Vetores , Nematoides/isolamento & purificação , Aedes/parasitologia , Aedes/virologia , Animais , Anopheles/parasitologia , Anopheles/virologia , Biodiversidade , Culex/parasitologia , Culex/virologia , Reservatórios de Doenças , Filariose/transmissão , Lemur , Madagáscar , Mosquitos Vetores/parasitologia , Mosquitos Vetores/virologia , Viroses/transmissão
16.
Emerg Infect Dis ; 27(3): 977-979, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33624579

RESUMO

We diagnosed tuberculosis in an illegally wild-captured pet ring-tailed lemur manifesting lethargy, anorexia, and cervical lymphadenopathy. Whole-genome sequencing confirmed the Mycobacterium tuberculosis isolate belonged to lineage 3 and harbored streptomycin resistance. We recommend reverse zoonosis prevention and determination of whether lemurs are able to maintain M. tuberculosis infection.


Assuntos
Lemur , Tuberculose Resistente a Múltiplos Medicamentos , Animais , Madagáscar
17.
Am J Phys Anthropol ; 175(1): 300-307, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33624841

RESUMO

OBJECTIVES: As many primates live in forests where visibility is limited, the ability to detect the aroma of distant fruit and navigate odor plumes would be highly adaptive. Our study is the first to investigate this ability with strepsirrhine primates. MATERIALS AND METHODS: We tested the ability of a group of ring-tailed lemurs to detect hidden fruit from afar using scent alone. We hid containers in the underbrush of a semi-natural forest, some baited with real cantaloupe and some with sham cantaloupe, 4-17 m from a path routinely used by the lemurs. Crucially, the containers were not visible from the path. Therefore, the lemurs had to use olfactory cues, but did not have to prioritize them to locate the bait. RESULTS: The lemurs found the real cantaloupe on days that the wind blew the scent of the fruit toward the trail. They did not find the sham cantaloupe. Upon detecting the odor of the bait, the lemurs sniffed the air at one or more locations as they moved toward the bait, a process of navigation known as klinotaxis. DISCUSSION: The traditional belief is that primates are unable to track odor plumes. The untrained lemurs in this study were able to detect the odor of the cantaloupe among the complex odors of the forest and navigate the odor plume to the fruit. The results indicate that olfaction may be used to respond to cues from distant sources. The ability to track odor plumes may be a critical foraging skill for strepsirrhines.


Assuntos
Comportamento Apetitivo/fisiologia , Frutas , Lemur/fisiologia , Olfato/fisiologia , Animais , Antropologia Física , Evolução Biológica , Feminino , Masculino
18.
Primates ; 62(2): 417-430, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33459940

RESUMO

Vocalizations are used by group-living animals as aggressive and submissive signals during agonistic interactions, and are also used to maintain dominance hierarchies in many species. For gregarious strepsirrhines with large vocal repertoires and differentiated dominance ranks like the ring-tailed lemur (Lemur catta), agonistic vocalization use is important to study to better understand their social adaptations.To determine whether ring-tailed lemur vocalizations such as the yip, cackle, twitter, chutter, and plosive bark were used as aggressive or submissive signals during agonism and uttered at different rates by males of differing dominance ranks and ages, 565 h of focal data were collected on 31 individual males aged ≥ 1 year from Beza Mahafaly Special Reserve, Madagascar. Yip, cackle, and twitter vocalizations were consistently used during agonistic submissive interactions with both males and females, chutter vocalizations were used during aggressive agonistic interactions with males and submissive agonistic interactions with males and females, and plosive bark vocalizations were used across behavioural contexts but not particularly during agonism. Males of all ages employed all vocalizations, and while low-ranking males uttered yip calls at higher rates, males of all dominance ranks uttered cackle, twitter, chutter, and plosive bark vocalizations. These results advance our knowledge of how male lemurs utilize agonistic vocalizations to maintain inter-individual relationships with males and females, and improve our overall understanding of the function of different agonistic vocalizations in wild lemurs.


Assuntos
Comportamento Agonístico , Lemur/fisiologia , Vocalização Animal , Animais , Feminino , Masculino , Comportamento Social , Predomínio Social
19.
Microb Ecol ; 82(1): 215-223, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33471174

RESUMO

Here, we investigated the possible linkages among geophagy, soil characteristics, and gut mycobiome of indri (Indri indri), an endangered lemur species able to survive only in wild conditions. The soil eaten by indri resulted in enriched secondary oxide-hydroxides and clays, together with a high concentration of specific essential micronutrients. This could partially explain the role of the soil in detoxification and as a nutrient supply. Besides, we found that soil subject to geophagy and indris' faeces shared about 8.9% of the fungal OTUs. Also, several genera (e.g. Fusarium, Aspergillus and Penicillium) commonly associated with soil and plant material were found in both geophagic soil and indri samples. On the contrary, some taxa with pathogenic potentials, such as Cryptococcus, were only found in indri samples. Further, many saprotrophs and plant-associated fungal taxa were detected in the indri faeces. These fungal species may be involved in the digestion processes of leaves and could have a beneficial role in their health. In conclusion, we found an intimate connection between gut mycobiome and soil, highlighting, once again, the potential consequent impacts on the wider habitat.


Assuntos
Indriidae , Lemur , Micobioma , Animais , Ecossistema , Pica , Microbiologia do Solo
20.
Primates ; 62(2): 431-441, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33180215

RESUMO

Digestive tract measurements are often considered species specific, but little information exists on the degree to which they change during ontogeny within a species. Additionally, access to anatomical material from nondomestic species is often limited, with fixed tissues possibly representing the only available source, though the degree to which this material is representative in terms of dimensions and weight is debatable. In the present study, the macroscopic anatomy of the digestive tract (length of intestinal sections, and tissue weights of stomach and intestines) of 58 Lemur catta [ranging in age from 1 month (neonates) to 25 years], which had been stored frozen (n = 27) or fixed in formalin (n = 31), was quantified. Particular attention was paid to the caecum and the possible presence of an appendix. The intraspecific allometric scaling of body mass (BM)0.46[0.40;0.51] for total intestine length and BM0.48[0.41;0.54] for small intestine length was higher than the expected geometric scaling of BM0.33, and similar to that reported in the literature for interspecific scaling. This difference in scaling is usually explained by the hypothesis that, to maintain optimal absorption, the diameter of the intestinal tube cannot increase geometrically. Therefore, geometric volume gain of increasing body mass is accommodated for by more-than-geometric length scaling. According to the literature, not all L. catta have an appendix. No appendix was found in the specimens in the present study. The proportions of length measurements did not change markedly during ontogeny, indicating that the proportions of the foetus are representative of those of the adult animal. By contrast, width and tissue-mass scaling of the caecum indicated disproportionate growth of this organ during ontogeny that was not reflected in its length. Compared to overall intraspecific variation, the method of storage (frozen vs. formalin) had no relevant impact on length or weight measurements.


Assuntos
Trato Gastrointestinal/anatomia & histologia , Lemur/anatomia & histologia , Manejo de Espécimes/métodos , Animais , Apêndice , Peso Corporal , Ceco/anatomia & histologia , Formaldeído , Congelamento , Trato Gastrointestinal/crescimento & desenvolvimento , Lemur/crescimento & desenvolvimento
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