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1

Madagascar 2  

NSDL National Science Digital Library

You will follow the directions of your teacher as you move through these different maps. Here is a link to the explanation of the project for teachers: Madagascar explanation You should have two copies of this map: Blank madagascar map to complete the exercise. Here's how you add a document from MyUEN to your IA project: Using UEN to link to a document from the IA Watch this movie about Madagascar. Think about where on this ...

Mr. Olsen

2010-02-23

2

Madagascar 1  

NSDL National Science Digital Library

You will follow the directions of your teacher as you move through these different maps. Here is a link to the explanation of the project for teachers: Madagascar Explanation 1 You should have two copies of this map: Blank madagascar map to complete the exercise. Here's how you add a document from MyUEN to your IA project: Using UEN to link to a document from the IA Watch this movie about Madagascar. Think about where on this ...

Brooke Robertshaw

2010-02-17

3

de Madagascar Dossier de presse  

E-print Network

Lémuriens de Madagascar Dossier de presse #12;Lémuriens de Madagascar -- 2 -- Les Publications scientifiques du Muséum & Conservation International présentent Lémuriens de Madagascar de Russell A, Lému- riens de Madagascar est publié par les Publica- tions scientifiques du Muséum national d

4

Conserving Madagascar's Freshwater Biodiversity  

NSDL National Science Digital Library

This peer-reviewed article from BioScience is about conserving freshwater diversity in Madagascar. The island nation of Madagascar, an international conservation priority, is now also recognized as a global hotspot for freshwater biodiversity. Three emerging characteristics of Madagascar's threatened freshwater biota deserve increased attention from the scientific and conservation communities. First, species richness is not low, as was once assumed for both the freshwater fishes and the invertebrates. Second, many species are restricted to a specific region or even to single river basins. Often these species are also limited to streams or rivers draining primary forest habitat. Finally, many of the island's freshwater fishes are basal taxa, having diverged earlier than any other extant members of their clade. As such, these taxa assume disproportional phylogenetic importance. In the face of ongoing environmental threats, links among microendemism, forest stream specialization, and basal phylogenetic position highlight the importance and vulnerability of these species and provide a powerful incentive for immediate conservation action.

JONATHAN P. BENSTEAD, PATRICK H. DE RHAM, JEAN-LUC GATTOLLIAT, FRAN?OIS-MARIE GIBON, PAUL V. LOISELLE, MICHEL SARTORI, JOHN S. SPARKS, and MELANIE L. J. STIASSNY (; )

2003-11-01

5

Trigonalidae (Hymenoptera) of Madagascar  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seven species of the primarily hyperparasitoid family Trigonalidae are reported from Madagascar: Orthogonalys brevis Smith and Tripotin, sp. n., Orthogonalys gigantea Benoit, 1951; O. hova Bischoff, 1933; O. maculata Bischoff, 1933; Orthogonalys parahova Smith and Tripotin, sp. n., O. seyrigi Bisch...

6

Oceanography of West Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Along selected hydrographical transects, a total of 182 CTD stations were conducted and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, along the west and south coast of Madagascar, the shelf is narrow and widen slightly along the north-west coast. In all ten transects the isotherms showed stratified waters from the coast to offshore. A maximum salinity layer was observed at subsurface in all transects. Dissolved oxygen had a maximum at around 500 m depth in all transects. Low fluorescence values were observed in the upper 150-200 m, with maximum values in the range of 0.14-0.22 g/l at intermediate layers. The conditions were consistent along and between the transects, with more variation observed at transect 9. No upwelling was observed along the western coast. The surface temperature (5 m depth) increased from 22C in the south to 26C in the north. The horizontal distribution of surface salinities showed homogenous conditions with values between 35.4psu (south) and 35.0 psu (north). Also starting from the coast to offshore, both the surface temperatures and surface salinities showed homogenous patterns.

John, Bemiasa

2014-05-01

7

Zooplankton of West Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Zooplankton samples were collected with Hydrobios Multinet at all environmental stations ranging from 200 m depth to the surface. The Multinet was equipped with 5 nets for depth-stratified sampling. The nets were fitted with 180 m mesh size and the water flow through the nets was measured. The Multinet was deployed and retrieved at a rate of ~ 1.5 m per second and was obliquely hauled. The five nets were triggered at the pre-selected depth intervals 0-25m, 25-50m, 50-80m, 80-120m and 120-200m. All samples were stored in marked bottles and preserved with buffered formaldehyde of 4% for further analysis. As results,the zooplankton abundance was influenced by physico-chemical factors. During the study period 34 Family of zooplankton were identified which are dominated by Copepoda (58,69%) followed by Radiolaria (12,06%), Appendicularia (6,47%), Sagitta (5,11%), Larvae (4,57%), Ostracoda (3,13%), pelagic Foraminifera (2,15%). Family of zooplankton with abundance <1% were also recorded, namely Salpidae (0,94%), Euphausiacea (0,44%), Tintinnidae (0,39%), Annlidae Polychtes (0,34%), Mysidacea (0,21%), Ptropodae (0,13%). Highest number of zooplankton were found at the depth below the maximum of fluorescence during the day. Copepods distribution depends on site and depth. During this study, the number of identified species is always superior to 50 for all sampling sites. The findings of the present study will help to improve the scientific knowledge of the marine ecosystem of the west coast of Madagascar.

Bemiasa, John; Remanevy, Sitraka

2014-05-01

8

Oceanography of East Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - September 2008) in Southern and Eastern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. A total of 102 CTD stations were conducted along selected hydrographical transects and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, the first section between latitude 25o-26oS showed sea surface temperature values ranging between 25oC to 15oC upper 250m depth. As part of the south-west, the shelf is narrow and widen slightly along the tip south of the Island coast. In contrast of the west coast, in all transects performed along the south and the east coast, in most cases, the isotherms showed non stratified waters from the coast to offshore. The presence of the upwelling system in the south-east coast modifies drastically the patterns of all measured parameters. Fluorescence had a maximum values (0.25 g/l) at surface near the coast in 2nd to 5th transects. Inversely, low temperature values were observed along the south and south-east with minimum values in the range of 18. 5oC-11oC at 50-250 m depth. These conditions were consistent along and between the 2nd to 5th transects, with more variation observed at transect 5. The salinity values (5 m depth) decreased from 35.7 psu in the south to 34.5 psu in the east. The horizontal distribution of oxygen showed non homogenous conditions with values between 5 ml/l (south) and 2.5 ml/l (south-east). Also starting from the coast to offshore, surface temperatures and surface salinities, surface fluorescence and dissolved oxygen showed non homogenous patterns.

Bemiasa, John

2014-05-01

9

Logistical teamwork tames Madagascar wildcats  

SciTech Connect

Amoco Production Company's exploration program in western Madagascar's Sakalaya coastal plain exemplifies the unique logistical challenges both operator and drilling contractor must undergo to reach the few remaining onshore frontier areas. Sakalava is characterized by deep rivers, flood prone tributaries, and a lone 40 km hard-surface road. Problems caused by a lack of port facilities and oil field services are complicated by thousands of square miles of unimproved wooded plains. Rainwater from the nearby mountains of central Madagascar frequently floods rivers in the Sakalava coastal plain leaving impassable marshes in their wake. Prior to this project, about 45 wells had been drilled in Madagascar. Most recently, state oil company Omnis contracted Bawden Drilling International Inc. to drill nine wells for its heavy oil project on the Tsimioro oil prospect. Bawden provided both logistical and drilling services for that program.

Twa, W.

1986-03-01

10

Resistances et initiatives a Madagascar (Resistance and Initiatives in Madagascar).  

ERIC Educational Resources Information Center

Discusses the cultural, political, and institutional barriers to population education in Madagascar and the strategies and initiatives that have been adopted to overcome them, including emphasizing the national character of a project, accommodating the values and ideals of the people involved, and assuring teachers of their classroom autonomy.

Georges, Claude

1993-01-01

11

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009  

E-print Network

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009 Influenza Centre, Institut Pasteur de Madagascar (IPM), Antananarivo, Madagascar, 2 Epidemiology Unit, IPM, Antananarivo, Madagascar Abstract Background: In Madagascar, despite an influenza surveillance established

Paris-Sud XI, Université de

12

Seizing an opportunity in Madagascar  

NSDL National Science Digital Library

Approximately 50 percent of plant and over 70 percent of vertebrate species are crammed into biodiversity "hotspots" that make up only 2.3 percent of Earth's land surface. Madagascar is one of these hotspots, and its government is planning to triple the amount of the protected land where the plants and animals can live without interference from humans.

American Association for the Advancement of Science (AAAS; )

2008-04-10

13

Relationships and traders in Madagascar  

Microsoft Academic Search

This article documents the role that personal relationships play in economic exchange. Original survey data show that agricultural traders in Madagascar perceive relationships as the most important factor for success in their business. Evidence details the extent to which relationships are used to serve a variety of purposes such as: the circulation of information about prices and market conditions; the

Marcel Fafchamps; Bart Minten

1999-01-01

14

The culture history of Madagascar  

Microsoft Academic Search

Madagascar's culture is a unique fusion of elements drawn from the western, northern, and eastern shores of the Indian Ocean, and its past has fascinated many scholars, yet systematic archaeological research is relatively recent on the island. The oldest traces of visitors are from the first century AD. Coastal settlements, with clear evidence of ties to the western Indian Ocean

Robert E. Dewar; Henry T. Wright

1993-01-01

15

Imperfect Isolation: Factors and Filters Shaping Madagascar's Extant Vertebrate Fauna  

E-print Network

Imperfect Isolation: Factors and Filters Shaping Madagascar's Extant Vertebrate Fauna Karen E, Illinois, United States of America, 5 Association Vahatra, Antananarivo, Madagascar, 6 Department a reconstruction of Madagascar's colonization events by vertebrate animals, but that information alone does

Vences, Miguel

16

Le got des ignames de Madagascar 1 valuation sensorielle de la perception des ignames de Madagascar,  

E-print Network

Le goût des ignames de Madagascar 1 ?valuation sensorielle de la perception des ignames de Madagascar, dans le contexte des connaissances actuelles en psychophysiologie de la gustation par Claude endémiques de Madagascar, nous avons entrepris des tests d'évaluation sensorielle qui nous sont apparus comme

Paris-Sud XI, Université de

17

Leptospirosis After a Stay in Madagascar.  

PubMed

We report a case of polymerase chain reaction (PCR)-confirmed leptospirosis in a patient who recently traveled to Madagascar, a country where only two cases have been reported since 1955. Although laboratory and clinical presentations were atypical and despite leptospirosis not being a documented disease in Madagascar, blood and urine tests for leptospirosis enabled retrospective confirmation of the diagnosis. PMID:25319525

Pags, Frdric; Kuli, Barbara; Moiton, Marie-Pierre; Goarant, Cyrille; Jaffar-Bandjee, Marie-Christine

2014-10-15

18

PODOSTEMACEAE OF AFRICAAND MADAGASCAR: KEYS TO GENERAAND SPECIES, INCLUDING GENERA  

E-print Network

I PODOSTEMACEAE OF AFRICAAND MADAGASCAR: KEYS TO GENERAAND SPECIES, INCLUDING GENERA DESCRIPTIONS and Madagascar. How to use the keys: There are 16 genera and c. 85 species known from Africa and Madagascar. KEY the DIAGNOSES to all genera. Eight out of the 16 genera occur with just one species in Africa and Madagascar

Zürich, Universität

19

Climate change in Madagascar; recent past and future February 2008  

E-print Network

Climate change in Madagascar; recent past and future February 2008 Mark Tadross1 , Luc Africa 2 National Meteorological Office, Antananarivo, Madagascar. #12;M. Tadross (mtadross@csag.uct.ac.za) Climate change in Madagascar 1 Climate change in Madagascar This report provides background information

Tadross, Mark

20

MADAGASCAR CONSERVATION & DEVELOPMENT VOLUME 5 | ISSUE 1 --JUNE 2010 PAGE 6 Madagascar rosewood, illegal logging and the  

E-print Network

MADAGASCAR CONSERVATION & DEVELOPMENT VOLUME 5 | ISSUE 1 -- JUNE 2010 PAGE 6 SPOTLIGHTS Madagascar issue for many countries. This is particularly true of Madagascar, where recent government instability Madagascar que de récents troubles politiques ont été accompagnés par une augmentation significative de l

21

Imperfect Isolation: Factors and Filters Shaping Madagascars Extant Vertebrate Fauna  

PubMed Central

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascars colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the islands biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the islands paleogeographical evolution to determine how particular events influenced the arrival of the islands extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascars tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the islands isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascars extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascars unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more recently arriving clades. Thus, the composition of Madagascars endemic vertebrate assemblage itself provides evidence of the island's paleogeographic history. PMID:23626770

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2013-01-01

22

Latitude drives diversification in Madagascar's endemic dry forest rodent Eliurus myoxinus  

E-print Network

Latitude drives diversification in Madagascar's endemic dry forest rodent Eliurus myoxinus, Madagascar 3 Association Vahatra, BP 3972, Antananarivo 101, Madagascar 4 Department of Zoology, Field Museum through western Madagascar. We sequenced the mitochondrial cytochrome b locus and nuclear introns

Yoder, Anne

23

Madagascar basalts: tracking oceanic and continental sources  

Microsoft Academic Search

Extensive Upper Cretaceous volcanism in southern Madagascar was fed in part by mantle sources resembling those expressed today in the Indian Ocean at Marion and Prince Edward islands and on the central Southwest Indian Ridge. In addition, very low ?Nd(T) (to -17.4), high (87Sr\\/86Sr)T (to 0.72126) tholeiites in southwestern Madagascar were variably but highly contaminated by ancient continental material broadly

J. Mahoney; C. Nicollet; C. Dupuy

1991-01-01

24

Phylogeography and Molecular Epidemiology of Yersinia pestis in Madagascar  

E-print Network

Phylogeography and Molecular Epidemiology of Yersinia pestis in Madagascar Amy J. Vogler1 , Fabien Epidemiology of Yersinia pestis in Madagascar. PLoS Negl Trop Dis 5(9): e1319. doi:10.1371/journal.pntd.0001319. pestis in Madagascar has been difficult to study due to the great genetic similarity among isolates. We

Boyer, Edmond

25

TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR  

E-print Network

TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR Lee Couch, Juha Laakkonen The Journal of #12;#12;TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR Lee Couch insectivorous mammals in Madagascar were collected between spring 1999 and fall 2001. In the Afrosoricida, 21

Jernvall, Jukka

26

Profil de poste Reprsentant de l'IRD Madagascar  

E-print Network

1 Profil de poste N° 3274 Représentant de l'IRD à Madagascar Catégorie A - Directeur de recherche. Affectation géographique Le représentant sera affecté à Antananarivo (Madagascar) à compter du 1 er Septembre 2014. ENVIRONNEMENT Les relations scientifiques entre l'IRD et Madagascar, et par extension avec les

27

Delimiting Species without Nuclear Monophyly in Madagascar's Mouse Lemurs  

E-print Network

Delimiting Species without Nuclear Monophyly in Madagascar's Mouse Lemurs David W. Weisrock1¨ttingen, Germany, 3 De´partement de Biologie Animale, Universite´ d'Antananarivo, Antananarivo, Madagascar, 4 Field, Madagascar, 6 Duke Lemur Center, Duke University, Durham, North Carolina, United States of America Abstract

Yoder, Anne

28

A Conservation Strategy for the Amphibians of Madagascar  

E-print Network

A Conservation Strategy for the Amphibians of Madagascar Monografie del Museo Regionale di Scienze,3 , Miguel VENCES4 Towards understanding the spatial pattern of amphibian diversity in Madagascar ABSTRACT We in Madagascar based on a comprehensive database of specimen and locality data records for Malagasy amphibians

Vences, Miguel

29

Sahonagasy Action Plan Conservation Programs for the Amphibians of Madagascar  

E-print Network

Sahonagasy Action Plan Conservation Programs for the Amphibians of Madagascar Programmes de Conservation pour les Amphibiens de Madagascar Edited by / Edité par Franco Andreone Herilala Randriamahazo ACSAM A Conservation Strategy for the Amphibians of Madagascar Une Stratégie de Conservation pour les

Andreone, Franco

30

POPULATION GENETIC ANALYSIS OF MYZOPODA (CHIROPTERA: MYZOPODIDAE) IN MADAGASCAR  

E-print Network

POPULATION GENETIC ANALYSIS OF MYZOPODA (CHIROPTERA: MYZOPODIDAE) IN MADAGASCAR AMY L. RUSSELL, Antananarivo 101, Madagascar (SMG) Department of Ecology and Evolutionary Biology, P.O. Box 90338, Duke is endemic to Madagascar and is characterized by several unique morphologies, such as sessile adhesive discs

Yoder, Anne

31

Effects of anthropogenic activities on lizard communities in northern Madagascar  

E-print Network

Effects of anthropogenic activities on lizard communities in northern Madagascar N. D'Cruze1 & S-1795.2011.00459.x Abstract Madagascar is a biodiversity hotspot threatened by habitat loss, which is detrimental and diversity among forest, clear-cut and orchard habitat types in Montagne des Franc¸ ais, north Madagascar

MacDonald, Lee

32

Pneumonic plague outbreak, Northern Madagascar, 2011.  

PubMed

Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466

Richard, Vincent; Riehm, Julia M; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C; Rajerison, Minoarisoa

2015-01-01

33

Pneumonic Plague Outbreak, Northern Madagascar, 2011  

PubMed Central

Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466

Richard, Vincent; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C.; Rajerison, Minoarisoa

2015-01-01

34

Investigating the Lithospheric Structure of Southern Madagascar  

NASA Astrophysics Data System (ADS)

The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data and cannot resolve the difference between eastern and western Madagascar. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the study area, where there is some so-far poorly characterised seismicity. We will present preliminary results on the lithospheric crust and mantle structure based on surface wave dispersion and waveform modelling, focussing on the contrast between the metamorphic areas in the east and the presumably stretched regions in the west. Station distribution Red diamonds: Temporary Broadband Light red squares: Short period Green: permanent stations Other temporary experiments: Open dark blue boxes: RHUM-RUM stations Open light blue boxes: MACOMO stations

Tilmann, F. J.; Yuan, X.; Rumpker, G.; Heit, B.; Rambolamana, G.; Rindraharisaona, E.; Priestley, K. F.

2013-12-01

35

Evolution in the hypervariable environment of Madagascar  

PubMed Central

We show that the diverse ecoregions of Madagascar share one distinctive climatic feature: unpredictable intra- or interannual precipitation compared with other regions with comparable rainfall. Climatic unpredictability is associated with unpredictable patterns of fruiting and flowering. It is argued that these features have shaped the evolution of distinctive characteristics in the mammalian fauna of the island. Endemic Herpestidae and Tenrecidae and members of five endemic primate families differ from closely related species elsewhere, exhibiting extremes of fastness and slowness in their life histories. Climatic features may also account for the dearth of frugivorous birds and mammals in Madagascar, and for the evolutionary prevalence of species with large body mass. PMID:17698810

Dewar, Robert E.; Richard, Alison F.

2007-01-01

36

Welfare dynamics in rural Kenya and Madagascar  

Microsoft Academic Search

This paper presents comparative qualitative and quantitative evidence from rural Kenya and Madagascar in an attempt to untangle the causality behind persistent poverty. We find striking differences in welfare dynamics depending on whether one uses total income, including stochastic terms and inevitable measurement error, or the predictable, structural component of income based on a household's asset holdings. Our results suggest

Christopher B. Barrett; Paswel Phiri Marenya; John Mcpeak; Bart Minten; Festus Murithi; Willis Oluoch-Kosura; Jean Claude Randrianarisoa; Jhon Rasambainarivo; Justine Wangila

2006-01-01

37

New Primates Discovered in Madagascar and Brazil  

NSDL National Science Digital Library

Nine lemur and two marmoset species native to the forests of Madagascar and Brazil, and new to (Western) science, were described earlier this month. Despite the excitement associated with this discovery, the forest habitats of most of these species appear to be already at risk from development pressures. This news brief from Environment News Service gives an overview of the discovery.

Lazaroff, Cat

2001-01-01

38

In and out of Madagascar: Dispersal to Peripheral Islands, Insular Speciation and Diversification of Indian  

E-print Network

In and out of Madagascar: Dispersal to Peripheral Islands, Insular Speciation and Diversification, University of St. Andrews, St. Andrews, Fife, United Kingdom Abstract Madagascar is surrounded, these archipelagos have accumulated disproportionate numbers of unique lineages in comparison to Madagascar

39

Sequential fatty acid analysis of a peat core covering the last two millennia (Tritrivakely lake, Madagascar)  

E-print Network

, Madagascar): Diagenesis appraisal and consequences for palaeoenvironmental reconstruction Jean-Robert Disnar, taken from the centre of the Tritrivakely maar lake (Madagascar) and covering the last 2300 yr, were in Madagascar. This sequence, which c

Boyer, Edmond

40

Molecular evolution and radiation of dung beetles in Madagascar Luisa Orsini*, Helena Koivulehto and Ilkka Hanski  

E-print Network

Molecular evolution and radiation of dung beetles in Madagascar Luisa Orsini*, Helena Koivulehto 65, FI-00014 University of Helsinki, Finland Accepted 19 September 2006 Abstract Madagascar taxonomic levels, making Madagascar one of the hotspots of global biodiversity. Dung beetles, represented

Hanski, Ilkka

41

Defining spatial and temporal patterns of phylogeographic structure in Madagascar's iguanid  

E-print Network

Defining spatial and temporal patterns of phylogeographic structure in Madagascar's iguanid lizards Department, University of Antananarivo, BP 906, Antananarivo 101, Madagascar, Association Vahatra, BP 3972, Antananarivo 101, Madagascar Abstract Understanding the remarkably high species diversity and levels

Yoder, Anne

42

A chronology for late prehistoric Madagascar  

Microsoft Academic Search

A database has been assembled with 278 age determinations for Madagascar. Materials 14C dated include pretreated sediments and plant macrofossils from cores and excavations throughout the island, and bones, teeth, or eggshells of most of the extinct megafaunal taxa, including the giant lemurs, hippopotami, and ratites. Additional measurements come from uranium-series dates on speleothems and thermoluminescence dating of pottery.Changes documented

David A Burney; Lida Pigott Burney; Laurie R Godfrey; William L Jungers; Steven M Goodman; Henry T Wright; A. J. Timothy Jull

2004-01-01

43

Investigating the Lithospheric Structure of Southern Madagascar  

NASA Astrophysics Data System (ADS)

The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly, although this interpretation has recently been questioned. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the study area, where there is some so-far poorly characterised seismicity. We present preliminary results on the lithospheric crust and mantle structure based on surface wave dispersion and waveform modelling, focussing on the contrast between the metamorphic areas in the east and the presumably stretched regions in the west. Interstation Green's functions have been obtained from all pairs of vertical broadband records, with coherent Rayleigh waves being identifiable for periods of 3-40 s. In addition, two-station phase dispersion measurements have allowed us to determine phase dispersion between 25 and 60 s. The ambient noise and earthquake data both indicate a slow-down of surface propagation in the western part of the array for periods < 40-45 s, but faster propagation in the western part for periods >45 s.

Tilmann, Frederik; Yuan, Xiaohui; Rmpker, Georg; Gerard, Rambolamana; Elisa, Rindraharisaona; Priestley, Keith

2014-05-01

44

Wintering habitats of Eleonora's Falcons Falco eleonorae in Madagascar  

Microsoft Academic Search

Capsule Eleonora's Falcons wintering in Madagascar selected degraded humid forests and cultivated areas close to pristine humid forest.Aims To identify the habitat preferences of Eleonora's Falcon Falco eleonorae on their wintering grounds in Madagascar, and to use this information to gain insights into the conservation priorities of this species.Methods A total of 11 Eleonora's Falcons were captured in Spain in

Ugo Mellone; Pascual Lpez-Lpez; Ruben Limiana; Vicente Urios

2012-01-01

45

Wintering habitats of Eleonora's Falcons Falco eleonorae in Madagascar  

Microsoft Academic Search

Capsule Eleonora's Falcons wintering in Madagascar selected degraded humid forests and cultivated areas close to pristine humid forest.Aims To identify the habitat preferences of Eleonora's Falcon Falco eleonorae on their wintering grounds in Madagascar, and to use this information to gain insights into the conservation priorities of this species.Methods A total of 11 Eleonora's Falcons were captured in Spain in

Ugo Mellone; Pascual Lpez-Lpez; Ruben Limiana; Vicente Urios

2011-01-01

46

Development of Environmental Education Programs for Protected Areas in Madagascar  

ERIC Educational Resources Information Center

Environmental education programs for schools in the peripheral zone of protected areas in Madagascar are still needed in numerous locations. My research investigated the status of environmental education and communication (EE&C) programs at Masoala National Park, Madagascar, as well as the attitudes of local residents toward the park and park

Ormsby, Alison

2007-01-01

47

When Madagascar produced natural rubber: a brief, forgotten yet informative history.  

E-print Network

1 When Madagascar produced natural rubber: a brief, forgotten yet informative history. P. Danthu (1) Cirad, URP "Forêts et Biodiversité", BP 853, Antananarivo, Madagascar and Campus de Baillarguet, 34398, Madagascar (3) Cirad, BP 853, Antananarivo, Madagascar* (4) Cirad, UMR Innovation/URP SCRID *Author

Boyer, Edmond

48

Breeding distribution and ecology of the threatened Madagascar Plover Charadrius thoracicus  

Microsoft Academic Search

The Madagascar Plover Charadrius thoracicus is a threatened wader endemic to Madagascar. We report the first detailed study of its distribution and breeding ecology. Madagascar Plovers breed on the west coast of Madagascar between the Mahavavy delta in the north and Fort-Dauphin in the south-east. Between 2002 and 2005, we found a total of 149 nests concentrated at two sites:

Sama Zefania; Peter R Long; Tams Szkely

49

An Abelisauroid Theropod Dinosaur from the Turonian of Madagascar  

PubMed Central

Geophysical evidence strongly supports the complete isolation of India and Madagascar (Indo-Madagascar) by ?100 million years ago, though sparse terrestrial fossil records from these regions prior to ?70 million years ago have limited insights into their biogeographic history during the Cretaceous. A new theropod dinosaur, Dahalokely tokana, from Turonian-aged (?90 million years old) strata of northernmost Madagascar is represented by a partial axial column. Autapomorphies include a prominently convex prezygoepipophyseal lamina on cervical vertebrae and a divided infraprezygapophyseal fossa through the mid-dorsal region, among others. Phylogenetic analysis definitively recovers the species as an abelisauroid theropod and weakly as a noasaurid. Dahalokely is the only known dinosaur from the interval during which Indo-Madagascar likely existed as a distinct landmass, but more complete material is needed to evaluate whether or not it is more closely related to later abelisauroids of Indo-Madagascar or those known elsewhere in Gondwana. PMID:23637961

Farke, Andrew A.; Sertich, Joseph J. W.

2013-01-01

50

Economie et enseignement a Madagascar. (Economy and Education in Madagascar.) Financement des systemes educatifs: etudes de cas Nationales 8.  

ERIC Educational Resources Information Center

The purpose of this volume is to analyze the problems of school finance in Madagascar, including those that have arisen in the past decade and those anticipated in the present decade (through 1980). More generally, this book examines past and future connections between the economic and educational systems in Madagascar. The author examines the

Hugon, Philippe

51

A Conservation Strategy for the Amphibians of Madagascar Une Stratgie de Conservation pour les Amphibiens de Madagascar  

E-print Network

1 A Conservation Strategy for the Amphibians of Madagascar Une Stratégie de Conservation pour les A conservation strategy for amphibians of Madagascar 08.30-09.00 Accueil des participants Welcome le Ministre The Minister La crise des amphibiens The amphibian crisis 09.30-09.50 Talk La

Andreone, Franco

52

[Plants and traditional medicine in southeast Madagascar].  

PubMed

This paper makes a first inventory of plants used by the medicine-men of the South-East of Madagascar (Tanala and Antemoro regions). The heirs - directly or indirectly - to an esoteric "moslem" knowledge which has been transmitted since the XVth century by the aristocratic islamized groups, the medicine-men are also the possessors of a knowledge which has been acquired by the autochthonous groups, that are said "masters of the earth" (commoners). Some divergences in the respective practices of the Tanala and Antemoro medicine-men seem to be connected with differences in the social structure and in the links between society and the environment. PMID:3193788

Beaujard, P

1988-01-01

53

The Madagascar Bloom: A serendipitous study  

NASA Astrophysics Data System (ADS)

The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon, and ends. It has been observed and studied using satellite ocean color observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made serendipitously on a cruise in February 2005. These show clearly for the first time the simultaneous existence of a deep chlorophyll maximum at ~70-110 m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature [seen in Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite ocean color data]. The observations also show the modulation of the biological signature at the surface by the eddy field but not of the deep chlorophyll maximum. Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. The surface bloom seen in the SeaWiFS data is confined to the shallow (~30 m) mixed layer. It is hypothesized that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

Srokosz, M. A.; Quartly, G. D.

2013-01-01

54

The Madagascar Bloom - a serendipitous study  

NASA Astrophysics Data System (ADS)

The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar, exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon and ends. It has been observed and studied using satellite ocean colour observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made on a cruise in February 2005 serendipitously. These show clearly for the first time the existence of both a deep chlorophyll maximum at ~70-110m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature (seen in SeaWiFS satellite ocean colour data). The observations also show the modulation of biological signature at the surface by the eddy field, but not apparently of the deep chlorophyll maximum. In situ observations indicate that Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. In addition, SeaSoar Optical Plankton Counter (OPC), temperature and salinity data suggest that the surface bloom seen in the SeaWiFS data is confined to the shallow (~30m) mixed layer. It is hypothesised that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

Srokosz, M. A.; Quartly, G.

2012-12-01

55

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual Phylogenetic Position in the  

E-print Network

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual from Madagascar is described and illustrated as a new species, Elaphoglossum nidusoides. We by the succulent fronds. KEYWORDS: Elaphoglossum, fern, Madagascar, new species, phylogeny, Squamipedia

56

Rift Valley Fever during Rainy Seasons, Madagascar, 2008 and 2009  

PubMed Central

During 2 successive rainy seasons, January 2008 through May 2008 and November 2008 through March 2009, Rift Valley fever virus (RVFV) caused outbreaks in Madagascar. Human and animal infections were confirmed on the northern and southern coasts and in the central highlands. Analysis of partial sequences from RVFV strains showed that all were similar to the strains circulating in Kenya during 20062007. A national cross-sectional serologic survey among slaughterhouse workers at high risk showed that RVFV circulation during the 2008 outbreaks included all of the Malagasy regions and that the virus has circulated in at least 92 of Madagascars 111 districts. To better predict and respond to RVF outbreaks in Madagascar, further epidemiologic studies are needed, such as RVFV complete genome analysis, ruminant movement mapping, and surveillance implementation. PMID:20507747

Andriamandimby, Soa Fy; Randrianarivo-Solofoniaina, Armand Eugne; Jeanmaire, Elisabeth M.; Ravololomanana, Lisette; Razafimanantsoa, Lanto Tiana; Rakotojoelinandrasana, Tsanta; Razainirina, Josette; Hoffmann, Jonathan; Ravalohery, Jean-Pierre; Rafisandratantsoa, Jean-Thophile; Rollin, Pierre E.

2010-01-01

57

Perspective The Challenge of Conserving Amphibian Megadiversity in Madagascar  

E-print Network

Frogs from Madagascar constitute one of the richest groups of amphibian fauna in the world, with currently 238 described species; caecilians and salamanders are absent [1]. Several frog radiations of the island are species-rich and parallel lemurs and tenrecs in their astonishing morphological and ecological diversity. According to the Global Amphibian Assessment (GAA), Madagascar ranks as the country with the 12th highest amphibian species richness [2,3] (see also

Franco Andreone; Angus I. Carpenter; Neil Cox; Louis Du Preez; Karen Freeman; Samuel Furrer; Gerardo Garcia; Frank Glaw; Julian Glos; David Knox; Jrn Khler; Joseph R. Mendelson; Vincenzo Mercurio; Russell A. Mittermeier; Robin D. Moore; Nirhy H. C. Rabibisoa; Herilala R; Harison R; Noromalala Rasoamampionona Raminosoa; Olga Ravoahangimalala Ramilijaona; Christopher J. Raxworthy; Denis Vallan; Miguel Vences; David R. Vieites; Ch Weldon

58

Worms, wells and water in western Madagascar.  

PubMed

This study of schistosomiasis and intestinal parasites was carried out on 496 children in the Firaisana (District) of Ankilivalo in Western Madagascar. The prevalence of these parasites was determined and data collected on nutrition, agriculture and the use of water in order to gain an understanding of the transmission and effects of these parasites. Recommendations for their control are suggested. In two schools within the area of a major irrigation scheme the prevalence of urinary schistosomiasis was 69%, and 50% suffer from at least one intestinal worm. In a school outside the main irrigation area, the prevalence of schistosomiasis was much lower (7%). Ultimately the control of schistosomiasis will depend on improvements to the irrigation and drainage infrastructure, and in standards of sanitation. However, chemotherapy is the only method of bringing the disease under control in the short term. PMID:3141630

Howarth, S E; Wilson, J M; Ranaivoson, E; Crook, S E; Denning, A M; Hutchings, M S

1988-10-01

59

Organic matter sources and early diagenetic degradation in a tropical peaty marsh (Tritrivakely, Madagascar). Implications for  

E-print Network

, Madagascar). Implications for environmental reconstruction during the Sub-Atlantic Sonia Bourdona , Fatima Peat samples from a one metre core and living Cyperaceae, collected in Tritrivakely marsh in Madagascar

Boyer, Edmond

60

Lmuriens de Madagascar Russell A. Mittermeier, Edward E. Louis Jr., Olivier Langrand, Christoph Schwitzer,  

E-print Network

& présentent Lémuriens de Madagascar de Russell A. Mittermeier, Edward E. Louis Jr., Olivier Illustrateur : Stephen D. Nash Ouvrage de référence sur le sujet, Lémuriens de Madagascar est publié par les Madagascar et de nombreuses espèces de lémuriens sont en danger, Lémuriens de Madagascar dresse l'état des

61

Kilometric to micrometric structures of the Madagascar granulitic crust and its relation with melt  

E-print Network

Kilometric to micrometric structures of the Madagascar granulitic crust and its relation with melt Republic Southern part of Madagascar Island exposes rocks equilibrated under granulite facies (800°C -6 important role in the development of Madagascar shear zones. #12;

62

Estimating the population size of an endangered shorebird, the Madagascar plover, using a habitat suitability model  

E-print Network

Estimating the population size of an endangered shorebird, the Madagascar plover, using a habitat, Antananarivo, Madagascar 3 School of Biosciences, University of Exeter in Cornwall, Penryn, Cornwall, UK 2007; accepted 19 December 2007 doi:10.1111/j.1469-1795.2008.00157.x Abstract The Madagascar plover

63

Transfert de gestion et conservation de la biodiversit de Makira, Nord-Est de Madagascar  

E-print Network

Transfert de gestion et conservation de la biodiversité de Makira, Nord-Est de Madagascar Avec sa biodiversité unique dans l'un des grands blocs de forêts humides de l'Est de Madagascar, les environnemental à Madagascar (Charte de l'Environnement, 1990 ; Mercier, 2009), donne aux communautés de base

Boyer, Edmond

64

Ital. J. Zool., Suppl. 2: 217-228 (2004) Origin of Madagascar's extant fauna: a  

E-print Network

Ital. J. Zool., Suppl. 2: 217-228 (2004) Origin of Madagascar's extant fauna: a perspective from@science.uva.nl ABSTRACT The origins of the highly endemic and partly very diverse fauna and flora of Madagascar were advocates of Gondwanan vicariance. Madagascar has been separated from other continents and continental

Vences, Miguel

65

Madagascar: an unexpected hotspot of social Anelosimus spider diversity (Araneae: Theridiidae)  

E-print Network

Madagascar: an unexpected hotspot of social Anelosimus spider diversity (Araneae: Theridiidae) I N, and no Ane- losimus species have yet been described from sub-Saharan Africa or Madagascar. Based on a preliminary phylogenetic analysis we predicted sociality in an unde- scribed Madagascar species because

Agnarsson, Ingi

66

Rice inventory credit in Madagascar : diversity of rural household strategies around an hybrid financial and  

E-print Network

Rice inventory credit in Madagascar : diversity of rural household strategies around an hybrid Madagascar (CECAM) propose à ses sociétaires un produit innovant de crédit stockage pour le riz depuis 1993 stockage, stratégies des ménages ruraux, Madagascar Abstract The Malagasy rural finance network CECAM has

Paris-Sud XI, Université de

67

The impact of advective transport by the South Indian Ocean Countercurrent on the Madagascar plankton bloom  

E-print Network

The impact of advective transport by the South Indian Ocean Countercurrent on the Madagascar­2007) of satellite ocean color data we analyze the spatiotemporal patterns in the seasonal Madagascar plankton bloom velocities we observe a narrow zonal jet that starts at $25 S at the southern tip of Madagascar, an important

Olascoaga, Maria Josefina

68

Age and paleoenvironment of the Maastrichtian to Paleocene of the Mahajanga Basin, Madagascar  

E-print Network

Age and paleoenvironment of the Maastrichtian to Paleocene of the Mahajanga Basin, Madagascar, University of Karlsruhe, D-76128 Karlsruhe, Germany f Muse¤e Akiba, PO Box 652, Mahajanga 401, Madagascar g De¤partment des Sciences de la Terre, Universite¤ de Mahajanga, Mahajanga, Madagascar Received 30 May

Keller, Gerta

69

Rev. col. (Terre Vie), vol. 62, 2007. LES IGNAMES (DIOSCOREA SPP.) DE MADAGASCAR  

E-print Network

Rev. ?col. (Terre Vie), vol. 62, 2007. ­ 191 ­ LES IGNAMES (DIOSCOREA SPP.) DE MADAGASCAR : ESP?CES.) of Madagascar: wild endemic and cultivated species; diversity, perception, nutritional value, and sustainable comparons la richesse en espèces endémiques d'ignames (Dioscorea spp.) d'une région de Madagascar au climat

Paris-Sud XI, Université de

70

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice  

E-print Network

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice or Asian rice is one of the key domesticated crop species in the world. The island of Madagascar off was introduced in Madagascar from India, the Malay Peninsula and Indonesia approximately 800­1400 years ago

Purugganan, Michael D.

71

Les mandres du dveloppement agricole au Lac Alaotra, Madagascar Entre inconstance politique et innovation technique  

E-print Network

1 Les méandres du développement agricole au Lac Alaotra, Madagascar Entre inconstance politique et, principal grenier à riz de Madagascar, région à forte immigration et zone de prédilection de l'aide publique, innovation, Lac Alaotra, Madagascar Summary The animated history of the evolution of agriculture of the Lake

Paris-Sud XI, Université de

72

ELSEVIER Earth and Planetary Science Letters 164 (1998) 221232 Late Cretaceous magmatism in Madagascar: palaeomagnetic evidence  

E-print Network

in Madagascar: palaeomagnetic evidence for a stationary Marion hotspot T.H. Torsvik a,b,L , R.D. Tucker c , L Cretaceous basaltic volcanics in the Morondava Basin (SW Madagascar) possess high-quality and pre of the tested basaltic flows. A precise U=Pb zircon­ baddeleyite age from northeast Madagascar demonstrates

Torsvik, Trond Helge

73

New colourful Liophidium from Madagascar All articles available online at http://www.salamandra-journal.com  

E-print Network

1 New colourful Liophidium from Madagascar All articles available online at http of colours from Madagascar: discovery of a remarkable new snake of the genus Liophidium and its phylogenetic, 0 Madagascar 3) Technical University of Braunschweig, Zoological Institute, Spielmannstra?e 8, 3806

74

Seasonal Variation of the South Equatorial Current Bifurcation off Madagascar ZHAOHUI CHEN AND LIXIN WU  

E-print Network

Seasonal Variation of the South Equatorial Current Bifurcation off Madagascar ZHAOHUI CHEN of the South Equatorial Current (SEC) bifurcation off the Madagascar coast in the upper south Indian Ocean (SIO to reproduce the seasonal cycle and the mean position of the SEC bifurcation off the Madagascar coast

Qiu, Bo

75

Springs and wire plants: anachronistic defences against Madagascar's extinct elephant birds  

E-print Network

Springs and wire plants: anachronistic defences against Madagascar's extinct elephant birds William the extinct moas. Madagascar, a larger tropical island, also had a fauna of large flightless birds searched the southern thickets of Madagascar for plants with putative anti-ratite defences and scored

Silander Jr., John A.

76

Excess mortality associated with the 2009 A(H1N1)v influenza pandemic in Antananarivo, Madagascar  

E-print Network

Excess mortality associated with the 2009 A(H1N1)v influenza pandemic in Antananarivo, Madagascar S. RAHARINANDRASANA2 , J.-M. HERAUD3 AND V. RICHARD1 * 1 Epidemiological Unit, Institut Pasteur de Madagascar, Antananarivo, Madagascar 2 Bureau Municipal d'Hygie`ne, Antananarivo, Madagascar 3 National Influenza Centre

Paris-Sud XI, Université de

77

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance  

E-print Network

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance Virology Unit, National Influenza Center, Institut Pasteur de Madagascar, Antananarivo, Madagascar, 3 Malagasy Ministry of Health, Antananarivo, Madagascar Abstract Background: The influenza A(H1N1)pdm09 virus

Paris-Sud XI, Université de

78

Malagasy dialects and the peopling of Madagascar  

PubMed Central

The origin of Malagasy DNA is half African and half Indonesian, nevertheless the Malagasy language, spoken by the entire population, belongs to the Austronesian family. The language most closely related to Malagasy is Maanyan (Greater Barito East group of the Austronesian family), but related languages are also in Sulawesi, Malaysia and Sumatra. For this reason, and because Maanyan is spoken by a population which lives along the Barito river in Kalimantan and which does not possess the necessary skill for long maritime navigation, the ethnic composition of the Indonesian colonizers is still unclear. There is a general consensus that Indonesian sailors reached Madagascar by a maritime trek, but the time, the path and the landing area of the first colonization are all disputed. In this research, we try to answer these problems together with other ones, such as the historical configuration of Malagasy dialects, by types of analysis related to lexicostatistics and glottochronology that draw upon the automated method recently proposed by the authors. The data were collected by the first author at the beginning of 2010 with the invaluable help of Joselin Soafara Nr and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the island. PMID:21632612

Serva, Maurizio; Petroni, Filippo; Volchenkov, Dima; Wichmann, Sren

2012-01-01

79

Current epidemiology of human plague in Madagascar.  

PubMed

From 1996 to 1998, 5,965 patients with suspected plague were identified in 38 districts of Madagascar (40% of the total population are exposed). Using standard bacteriology, 917 of them were confirmed or presumptive (C + P) cases. However, more than 2,000 plague cases could be estimated using F1 antigen assay. Two out of the 711 Yersinia pestis isolates tested were resistant to chloramphenicol and to ampicillin (both isolates found in the harbour of Mahajanga). Urban plague (Mahajanga harbour and Antananarivo city) accounted for 37.4% of the C + P cases. Bubonic plague represented 97.2% of the cases, and the lethality rate was still high (20%). In comparing the exposed population, plague was more prevalent in males (M:F sex ratio 1.3:1) and patients under 20 years (2.7% babies under two years). Buboes were mainly localised in the inguinal/femoral regions (55.8%). The epidemiological risk factors are discussed. PMID:10717537

Chanteau, S; Ratsitorahina, M; Rahalison, L; Rasoamanana, B; Chan, F; Boisier, P; Rabeson, D; Roux, J

2000-01-01

80

[Seroepidemiologic study of human plague in Madagascar].  

PubMed

An IgG anti-F1 Enzyme linked immunosorbent assay (Elisa) has been developed for plague diagnosis in the Malagasy republic. The sensitivity of the test was 91.4% and the specificity 98.5%. This technique is cheap and the cross reaction with other infections diseases prevalent in Madagascar is very limited. During the urban plague outbreak (Mahajanga city, 1995), the positive predictive value and the negative predictive value were 95.2% and 97% respectively. During this outbreak, the usefulness of the Elisa test for retrospective individual serodiagnosis was confirmed. Furthermore, the test confirmed plague among suspect patients without bacteriological diagnosis. The test was used for a sero-epidemiological study. Eight villages in the endemic area were investigated and 900 persons were studied. The overall seroprevalence was 6 times the officially prevalence of plague, notified at the Central Plague Laboratory. A large disparity of the seroprevalence was observed in the endemic area, with variation from < 1.5% to 15.5%. A high incidence of asymptomatic infections due to Yersinia pestis was found. PMID:9309233

Leroy, F

1997-01-01

81

Cretaceous may hold promise in Majunga basin, Madagascar  

SciTech Connect

Recent drilling in the Majunga basin of northwestern Madagascar revealed unexpected light oil shows in excellent quality reservoir sands of Mid-Cretaceous age. Regional reconstructions show the development of a prograding clastic shelf from the Aptian until the Mid-Turonian that extended laterally from the northwest costs of Madagascar into Northwest India and Southeast Pakistan. Six untested play concepts have been identified in Cretaceous reservoirs of the Majunga basin. These plays offer multiple objectives in the depth range of 800--2,500 m within a well defined area. Further untested plays exist for Tertiary and Dogger objectives. The paper describes the geologic setting, exploration history the Cretaceous reservoirs, source rocks, and other potential plays. Political changes in Madagascar the last four years have led to an open door policy for foreign investment. Favorable terms are on offer for investment in the petroleum sector, and high potential exists for development on this island continent.

Lalaharisaina, J.V. (Office des Mines Nationales et des Industries Stategiques, Antananarivo (Madagascar)); Ferrand, N.J. (Oil and Gas Consultants, Palaiseau (France))

1994-08-01

82

Madagascar: Heads It's a Continent, Tails It's an Island  

NASA Astrophysics Data System (ADS)

Neither geologists nor biologists have a definition that is capable of classifying Madagascar unambiguously as an island or a continent; nor can they incorporate Malagasy natural history into a single model rooted in Africa or Asia. Madagascar is a microcosm of the larger continents, with a rock record that spans more than 3000 million years (Ma), during which it has been united episodically with, and divorced from, Asian and African connections. This is reflected in its Precambrian history of deep crustal tectonics and a Phanerozoic history of biodiversity that fluctuated between cosmopolitanism and parochialism. Both vicariance and dispersal events over the past 90 Ma have blended a unique endemism on Madagascar, now in decline following rapid extinctions that started about 2000 years ago.

de Wit, Maarten J.

83

Autochthonous melioidosis in humans, Madagascar, 2012 and 2013.  

PubMed

Melioidosis is an often fatal infectious disease affecting humans and animals in the tropics. Only sporadic cases have been reported from Africa and the Indian Ocean region. We describe 2 confirmed autochthonous cases of human melioidosis in Madagascar, both from novel genotypes of Burkholderia pseudomallei. PMID:25272365

Garin, Benoit; Djaomazala, Innocente; Dubois-Cauwelaert, Natasha; Raharimanga, Vaomalala; Ralison, Fidiarivony; Herindrainy, Perlinot; Andriamalala, Nivosoa C; Sarovich, Derek S; Mayo, Mark; Kaestli, Mirjam; Currie, Bart J

2014-10-01

84

Family Background, School Characteristics, and Children's Cognitive Achievement in Madagascar  

ERIC Educational Resources Information Center

This paper uses linked household, school, and test score data from Madagascar to investigate the relation of household characteristics and school factors to the cognitive skills of children ages 8-10 and 14-16. In contrast to most achievement test studies in developing countries, the study uses representative rather than school-based samples of

Glick, Peter; Randrianarisoa, Jean Claude; Sahn, David E.

2011-01-01

85

Cyclopoid copepods associated with antipatharian coelenterates in Madagascar  

Microsoft Academic Search

Previous work (in i960) at Nosy B, in northwestern Madagascar, resulted in the collection by dredging of the antipatharian Stichopathes echinulata Brook parasitized by the copepod Vahinius petax Humes, 1967. More recently (in 1964 and 1967) I have obtained by SCUBA diving several other antipatharians with which the copepods described below were associated. The collection in 1964 was made as

A. G. Humes

1969-01-01

86

Food Marketing Liberalization and Trader Entry: Evidence from Madagascar  

Microsoft Academic Search

Food marketing liberalization was expected to induce massive trader entry and competitive markets in Africa. Despite evidence of trader entry, enterprise expansion remains difficult and many claim market power persists, though perhaps in different hands. This paper confronts this puzzle of substantial market entry that might not foster competition. Data from Madagascar reveal distinct groups within rural food marketing channels,

Christopher B. Barrett

1997-01-01

87

Satellite imagery, human ecology, anthropology, and deforestation in Madagascar  

Microsoft Academic Search

Satellite images were used to determine rates of deforestation over the past 35 years and to identify current deforestation hotspots in the eastern rainforests and in the dry endemic forests of southern Madagascar. The analysis of population trends, topography, and coincident ethnographic research points to a number of different factors influencing deforestation in these regions. Each of these factors generates

Robert W. Sussman; Glen M. Green; Linda K. Sussman

1994-01-01

88

Lemur Habitat and Dental Senescence in Ranomafana National Park, Madagascar  

E-print Network

, the wear-related decrease in dental functionality that is associated with decreased survival of infants meetings of the American Association of Physical Anthropologists in Albuquerque, New Mexico in April, 2010Lemur Habitat and Dental Senescence in Ranomafana National Park, Madagascar Stephen J. King,1

Boyer, Doug M.

89

A Conservation Strategy for the Amphibians of Madagascar  

E-print Network

A Conservation Strategy for the Amphibians of Madagascar Monografie del Museo Regionale di Scienze of Braunschweig, Braunschweig. Ché WELDON1 , Louis DU PREEZ1 , Miguel VENCES2 Lack of detection of the amphibian chytridiomycosis can have catastrophic effects on amphibian populations leading to declines and even extinctions

Vences, Miguel

90

Autochthonous Melioidosis in Humans, Madagascar, 2012 and 2013  

PubMed Central

Melioidosis is an often fatal infectious disease affecting humans and animals in the tropics. Only sporadic cases have been reported from Africa and the Indian Ocean region. We describe 2 confirmed autochthonous cases of human melioidosis in Madagascar, both from novel genotypes of Burkholderia pseudomallei. PMID:25272365

Djaomazala, Innocente; Dubois-Cauwelaert, Natasha; Raharimanga, Vaomalala; Ralison, Fidiarivony; Herindrainy, Perlinot; Andriamalala, Nivosoa C.; Sarovich, Derek S.; Mayo, Mark; Kaestli, Mirjam; Currie, Bart J.

2014-01-01

91

Antimicrobial resistance of bacterial enteropathogens isolated from stools in Madagascar  

PubMed Central

Background Diarrheal diseases are a major public health problem in developing countries, and are one of the main causes of hospital admissions in Madagascar. The Pasteur Institute of Madagascar undertook a study to determine the prevalence and the pathogenicity of bacterial, viral and protozoal enteropathogens in diarrheal and non-diarrheal stools of children aged less than 5years in Madagascar. We present here the results of the analysis of antimicrobial susceptibility of the bacteria isolated during this study. Methods The study was conducted in the community setting in 14 districts of Madagascar from October 2008 to May 2009. Conventional methods and PCR were used to identify the bacteria; antimicrobial susceptibility was determined using an agar diffusion method for enterobacteriaceae and MICs were measured by an agar dilution method for Campylobacter sp. In addition to the strains isolated during this study, Salmonella sp and Shigella sp isolated at the Pasteur Institute of Madagascar from 2005 to 2009 were included in the analysis to increase the power of the study. Results Twenty-nine strains of Salmonella sp, 35 strains of Shigella sp, 195 strains of diarrheagenic E. coli, 203 strains of C. jejuni and 71 strains of C. coli isolated in the community setting were tested for antibiotic resistance. Fifty-five strains of Salmonella sp and 129 strains of Shigella sp isolated from patients referred to the Pasteur Institute of Madagascar were also included in the study. Many E. coli and Shigella isolates (around 80%) but fewer Salmonella isolates were resistant to ampicillin and trimethoprim/sulfamethoxazole. A small proportion of strains of each species were resistant to ciprofloxacin and only 3% of E. coli strains presented a resistance to third generation cephalosporins due to the production of extended-spectrum beta-lactamases. The resistance of Campylobacter sp to ampicillin was the most prevalent, whereas less than 5% of isolates were resistant to each of the other antibiotics. Conclusion The highest prevalence of antimicrobial resistance was to ampicillin and trimethoprim/sulfamethoxazole. Antibiotic treatment is not recommended for children with diarrhea in Madagascar and the emphasis should be placed on oral rehydration. PMID:24568189

2014-01-01

92

Corps de la Paix Madagascar Livre du Stagiare. Langue: Malagasy Ofisialy (Peace Corps Madagascar Volunteer Manual. Language: Official Malagasy).  

ERIC Educational Resources Information Center

This manual for Malagasy is designed for the specific language instruction needs of Peace Corps personnel working in Madagascar. It is written primarily in English and Malagasy, with introductory sections in French. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on needed materials,

Tshiangale, Mupemba Wa

93

Corps de la Paix Madagascar Livre du Formateur. Langue: Sakalava (Peace Corps Madagascar Teacher's Manual. Language: Sakalava).  

ERIC Educational Resources Information Center

This teacher's manual for Sakalava, a dialect of Malagasy, is designed for the specific language instruction needs of Peace Corps personnel in Madagascar. It is written primarily in French and Sakalava, with some titles in English. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on

Tshiangale, Mupemba Wa

94

The Application of TOMS Ozone, Aerosol and UV-B Data to Madagascar Air Quality Determination  

NASA Technical Reports Server (NTRS)

Total Ozone Mapping Spectrometer (TOMS) data products for the area of Madagascar are presented. In addition to total ozone, aerosols and UV-B tropospheric ozone results are shown from 1979 to the present. Tropospheric ozone over Africa and Madagascar is enhanced by 10 to 15 DU in October. This maximum coincides with the time of maximum biomass area burning in Africa and Madagascar. Ozone observations were made from 1979 to 1999 using the TOMS tropospheric ozone convective cloud differential method. As a result of easterly trade winds, ozone originating on Madagascar is transported to the west over the Mozambique Channel. In El Nino years higher level westerly winds descend to transport low level ozone easterly. This results in African continental ozone being transported east of Madagascar. Long range transport of African ozone is observed during El Nino periods. The potential of TOMS and other space data for use in public education and research on Madagascar air quality is demonstrated.

Aikin, A.C.; Einaudi, Franco (Technical Monitor)

2000-01-01

95

IDiversite et Endemisme a Madagascar pp : 229-242 Aout 2000 ISBN 2-903700-04-4 \\ POLYPHYLY OF TOMOPTERNA (AMPHIBIA: RANIDAE) BASED ON  

E-print Network

of Tomopterna are not informative regarding continental drift and biogeographic Madagascar-India relationships, Molecular phylogeny, Madagascar, India, South Africa, Continental drift, Reproductive modes RESUME.- Les

96

Madagascar 1972 : l'autre indpendance. Une rvolution contre les accords de coopration  

E-print Network

1 Madagascar 1972 : l'autre indépendance. Une révolution contre les accords de coopération En mai 1972, douze ans après le 26 juin 19601 , Madagascar a vécu une Révolution. Ses acteurs contestaient la nombre de 11 pour Madagascar. En 1972, la convention d'établissement et les accords portant sur l

Paris-Sud XI, Université de

97

Rationalit des actions dans les socits sans criture: Les mathmatiques de la divination sikidy Madagascar  

E-print Network

sikidy à Madagascar Marc CHEMILLIER Laboratoire CNRS UMR 8574 Musée de l'Homme 17 place. du Trocadéro'action, la construction de tableaux géomantiques dans la divination sikidy à Madagascar. Ces tableaux sont préparatoire à Madagascar, premiers essais de tests chronométriques Hiver 2001-2002 : analyse des données, et

Paris-Sud XI, Université de

98

Les mandres du dveloppement agricole au Lac Alaotra, Madagascar Entre inconstance politique et innovation technique  

E-print Network

1 Les méandres du développement agricole au Lac Alaotra, Madagascar Entre inconstance politique et Antananarivo, Madagascar Discipline ; socio-économie Téléphone : 00 261 (0) 34 044 63 29 Penot@cirad.fr Résumé Madagascar, région à forte immigration et zone de prédilection de l'aide publique au développement, est

Paris-Sud XI, Université de

99

SITES LMURIENS SACRS EN PAYS SAKALAVA, AU NORD-OUEST DE MADAGASCAR  

E-print Network

-- 291 -- NOTE BR?VE SITES ? L?MURIENS SACR?S EN PAYS SAKALAVA, AU NORD-OUEST DE MADAGASCAR : R?*, Vololoniaina JEANNODA** et Claude Marcel HLADIK* SUMMARY The two sites of the northwest of Madagascar, where référence à des sites de Madagascar où une espèce de lémurien, Eulemur macaco, considérée comme sacrée, est

Paris-Sud XI, Université de

100

ans les zones de moyenne altitude de Madagascar, les systmes de culture fonds sur le  

E-print Network

D ans les zones de moyenne altitude de Madagascar, les systèmes de culture fondés sur le semis et ses partenaires du développement à Madagascar ont mis au point des outils de modélisation pour le avec couverture végétale à Madagascar Développer une démarche d'apprentissage Visite de terrain et

Boyer, Edmond

101

Possible Fruit Protein Effects on Primate Communities in Madagascar and the Neotropics  

PubMed Central

Background The ecological factors contributing to the evolution of tropical vertebrate communities are still poorly understood. Primate communities of the tropical Americas have fewer folivorous but more frugivorous genera than tropical regions of the Old World and especially many more frugivorous genera than Madagascar. Reasons for this phenomenon are largely unexplored. We developed the hypothesis that Neotropical fruits have higher protein concentrations than fruits from Madagascar and that the higher representation of frugivorous genera in the Neotropics is linked to high protein concentrations in fruits. Low fruit protein concentrations in Madagascar would restrict the evolution of frugivores in Malagasy communities. Methodology/Principal Findings We reviewed the literature for nitrogen concentrations in fruits from the Neotropics and from Madagascar, and analyzed fruits from an additional six sites in the Neotropics and six sites in Madagascar. Fruits from the Neotropical sites contain significantly more nitrogen than fruits from the Madagascar sites. Nitrogen concentrations in New World fruits are above the concentrations to satisfy nitrogen requirements of primates, while they are at the lower end or below the concentrations to cover primate protein needs in Madagascar. Conclusions/Significance Fruits at most sites in the Neotropics contain enough protein to satisfy the protein needs of primates. Thus, selection pressure to develop new adaptations for foods that are difficult to digest (such as leaves) may have been lower in the Neotropics than in Madagascar. The low nitrogen concentrations in fruits from Madagascar may contribute to the almost complete absence of frugivorous primate species on this island. PMID:20016841

Ganzhorn, Jrg U.; Arrigo-Nelson, Summer; Boinski, Sue; Bollen, An; Carrai, Valentina; Derby, Abigail; Donati, Giuseppe; Koenig, Andreas; Kowalewski, Martin; Lahann, Petra; Norscia, Ivan; Polowinsky, Sandra Y.; Schwitzer, Christoph; Stevenson, Pablo R.; Talebi, Mauricio G.; Tan, Chia; Vogel, Erin R.; Wright, Patricia C.

2009-01-01

102

Landscape archaeology and remote sensing in southern Madagascar  

Microsoft Academic Search

This paper demonstrates how remote sensing can be used to aid the general approach of landscape archaeology. The methodology and results of a project attempting to elucidate links and controls between environmental change and long-term social change in southern Madagascar are outlined. Multi-seasonal Landsat TM images, SPOT panchromatic and ERS-1 SAR images are used to produce a number of outputs.

C. D. CLARK; S. M. GARROD; M. PARKER PEARSON

1998-01-01

103

AVHRR-LAC estimates of forest area in Madagascar, 1990  

Microsoft Academic Search

Three AVHRR-LAC data sets acquired in September 1990 and January 1991 were used to map the forest resources of Madagascar. The island was partitioned into four strata to include: (1) the western hardwoods, (2) the central grasslands, (3) the eastern rainforest, and (4) spiny forest. Each stratum was classified separately using AVHRR-LAC data in conjunction with 1984-1988 Landsat-MSS photoproducts. The

R. Nelson; N. Horning

1993-01-01

104

Strain pattern and late Precambrian deformation history in southern Madagascar  

Microsoft Academic Search

This paper examines the thermo-mechanical evolution of the lower crust, in Precambrian times, with an example from southern Madagascar. The finite strain pattern is derived from the study of satellite images complemented by field structural analysis. The finite geometry reflects the superposition of two distinct finite strain patterns, D1 and D2. The geodynamic significance of the D1 event remains unclear.

Jean-Emmanuel Martelat; Jean-Marc Lardeaux; Christian Nicollet; Raymond Rakotondrazafy

2000-01-01

105

Field Museum Researchers Help Trace Origin of Madagascar's Mammals  

NSDL National Science Digital Library

Chicago's Field Museum of Natural History (FMNH) Web site currently features museum-sponsored research on the phylogeny of Madagascar's living Carnivora. Previously thought to represent two to four separate lineages, the island's carnivores are now known to have descended from a single species. These findings, recently published in the journal Nature, are presented in the FMNH Web site as a 4-page press release that should appeal to general readers as well as interested researchers.

2003-01-01

106

Multiple Miocene Melastomataceae dispersal between Madagascar, Africa and India.  

PubMed Central

Melastomataceae sensu stricto (excluding Memecylaceae) comprise some 3000 species in the neotropics, 1000 in Asia, 240 in Africa, and 230 in Madagascar. Previous family-wide morphological and DNA analyses have shown that the Madagascan species belong to at least three unrelated lineages, which were hypothesized to have arrived by trans-oceanic dispersal. An alternative hypothesis posits that the ancestors of Madagascan, as well as Indian, Melastomataceae arrived from Africa in the Late Cretaceous. This study tests these hypotheses in a Bayesian framework, using three combined sequence datasets analysed under a relaxed clock and simultaneously calibrated with fossils, some not previously used. The new fossil calibration comes from a re-dated possibly Middle or Upper Eocene Brazilian fossil of Melastomeae. Tectonic events were also tentatively used as constraints because of concerns that some of the family's fossils are difficult to assign to nodes in the phylogeny. Regardless of how the data were calibrated, the estimated divergence times of Madagascan and Indian lineages were too young for Cretaceous explanations to hold. This was true even of the oldest ages within the 95% credibility interval around each estimate. Madagascar's Melastomeae appear to have arrived from Africa during the Miocene. Medinilla, with some 70 species in Madagascar and two in Africa, too, arrived during the Miocene, but from Asia. Gravesia, with 100 species in Madagascar and four in east and west Africa, also appears to date to the Miocene, but its monophyly has not been tested. The study afforded an opportunity to compare divergence time estimates obtained earlier with strict clocks and single calibrations, with estimates based on relaxed clocks and different multiple calibrations and taxon sampling. PMID:15519967

Renner, Susanne S

2004-01-01

107

Extinction Risks and the Conservation of Madagascar's Reptiles  

PubMed Central

Background An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island's biodiversity. PMID:25111137

Jenkins, Richard K. B.; Tognelli, Marcelo F.; Bowles, Philip; Cox, Neil; Brown, Jason L.; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R.; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D.; Hantalalaina, Elisoa F.; Glaw, Frank; Griffiths, Richard A.; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H.; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A.; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J. Christian; Randrianasolo, Harison H.; Randrianirina, Jasmin E.; Randrianizahana, Hiarinirina; Raselimanana, Achille P.; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M.; Raxworthy, Christopher J.; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P.; Yoder, Anne D.; Vences, Miguel

2014-01-01

108

Xenopsylla cheopis (Siphonaptera: Pulicidae) Susceptibility to Deltamethrin in Madagascar  

PubMed Central

The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

Elissa, Nohal

2014-01-01

109

Xenopsylla cheopis (Siphonaptera: Pulicidae) susceptibility to Deltamethrin in Madagascar.  

PubMed

The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

Boyer, Sebastien; Miarinjara, Adlade; Elissa, Nohal

2014-01-01

110

A geological synthesis of the Precambrian shield in Madagascar  

USGS Publications Warehouse

Available UPb geochronology of the Precambrian shield of Madagascar is summarized and integrated into a synthesis of the regions geological history. The shield is described in terms of six geodynamic domains, from northeast to southwest, the Bemarivo, AntongilMasora, Antananarivo, Ikalamavony, AndroyanAnosyan, and Vohibory domains. Each domain is defined by distinctive suites of metaigneous rocks and metasedimentary groups, and a unique history of Archean (?2.5 Ga) and Proterozoic (?1.0 Ga, ?0.80 Ga, and ?0.55 Ga) reworking. Superimposed within and across these domains are scores of Neoproterozoic granitic stocks and batholiths as well as kilometer long zones of steeply dipping, highly strained rocks that record the effects of Gondwanas amalgamation and shortening in latest Neoproterozoic time (0.5600.520 Ga). The present-day shield of Madagascar is best viewed as part of the Greater Dharwar Craton, of Archean age, to which three exotic terranes were added in Proterozoic time. The domains in Madagascar representing the Greater Dharwar Craton include the AntongilMasora domain, a fragment of the Western Dharwar of India, and the Neoarchean Antananarivo domain (with its Tsaratanana Complex) which is broadly analogous to the Eastern Dharwar of India. In its reconstructed position, the Greater Dharwar Craton consists of a central nucleus of Paleo-Mesoarchean age (>3.1 Ga), the combined Western Dharwar and AntongilMasora domain, flanked by mostly juvenile granitegreenstone belts of Neoarchean age (2.702.56 Ga). The age of the accretionary event that formed this craton is approximately 2.52.45 Ga. The three domains in Madagascar exotic to the Greater Dharwar Craton are the AndroyanAnosyan, Vohibory, and Bemarivo. The basement to the AndroyanAnosyan domain is a continental terrane of Paleoproterozoic age (2.01.78 Ga) that was accreted to the southern margin (present-day direction) of the Greater Dharwar Craton in pre-Stratherian time (>1.6 Ga), and rejuvenated at 1.030.93 Ga with the creation of the Ikalamavony domain. The Vohibory domain, an oceanic terrane of Neoproterozoic age was accreted to the AndroyanAnosyan domain in Cryogenian time (?0.630.60 Ga). The Bemarivo domain of north Madagascar is a terrane of Cryogenian igneous rocks, with a cryptic Paleoproterozoic basement, that was accreted to the Greater Dharwar Craton in latest Ediacaran to earliest Cambrian time (0.530.51 Ga).

Tucker, Robert D.; Roig, J.Y.; Moine, B.; Delor, C.; Peters, S.G.

2014-01-01

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The modern diatom spectra of Madagascar and diatom-inferred Late Quaternary climatic changes in northeastern and central Madagascar  

SciTech Connect

A study was conducted to classify diatoms in modern sediment surface samples in freshwater sites into assemblages and to assess the historical changes in lake level changes and climatic conditions in Madagascar during the Late Quaternary. Analysis of taxonomic percentages of diatoms in recently deposited sediments from various sites shows that diatom communities in these sites can be grouped by means of cluster analysis into distinct assemblages, some of which show similarities to groupings found in East Africa. pH and conductivity appear to be important factors correlating with differences in diatom communities in these study sites. Trends in diatom assemblages in a sediment core taken from Lake Alaotra, supplemented by those in sediments of the paleolake Ampasambazimba, suggest that the late Pleistocene in northeastern Madagascar was arid, though aridity was probably not as constant or as severe as in many areas of eastern and northern Africa; the Holocene was a period of moderate but variable conditions, marked by a distinct dry episode ca 5000 yr B.P. and a drying trend toward the late Holocene. Changes in diatom assemblages in a sediment core from Lake Kavitaha in central Madagascar suggest changes in the surrounding environment during at least two periods in the late Holocene. These coincide with increases in charcoal influx and, around 700 yr B.P., with the intensification of agricultural activity in the area.

Reyes, N.E.

1993-01-01

112

November 2003 / Vol. 53 No. 11 BioScience 1101 Madagascar lies 400 kilometers off the African  

E-print Network

November 2003 / Vol. 53 No. 11 BioScience 1101 Articles Madagascar lies 400 kilometers off, Madagascar is often considered by biogeographers as more of a "micro- continent." Its complex topography biologists. However, Madagascar is also noteworthy because it broke away from Africa about 160 million years

Benstead, Jon

113

SIMULATION OF A TYPICAL HOUSE IN THE REGION OF ANTANANARIVO, MADAGASCAR DETERMINATION OF PASSIVE SOLUTIONS USING LOCAL MATERIALS  

E-print Network

SIMULATION OF A TYPICAL HOUSE IN THE REGION OF ANTANANARIVO, MADAGASCAR DETERMINATION OF PASSIVE to the climate of the highlands of Madagascar. While the strongest population density is located in the central of living of the country. Keywords: Madagascar, Insulation, Passive solutions, Thermal comfort 1

Boyer, Edmond

114

Evaluation des dispositifs de gestion communautaire (DGC) Madagascar : une application de la dmarche d'analyse multicritres  

E-print Network

Evaluation des dispositifs de gestion communautaire (DGC) à Madagascar : une application de la démarche d'analyse multicritères Fano Andriamahefazafy Chercheur Economiste - C3ED Madagascar Université d'Antananarivo ­ Faculté DEGS BP 905, Antananarivo 101, Madagascar Résumé La gestion communautaire de l'environnement et

Paris-Sud XI, Université de

115

Bulletin de l'Acadmie Nationale des Arts, Lettres et Sciences (Antananarivo, Madagascar), vol 82 pp 491-500 (2004)  

E-print Network

1 Bulletin de l'Académie Nationale des Arts, Lettres et Sciences (Antananarivo, Madagascar), vol 82 pp 491-500 (2004) Evaluation sensorielle de la perception des ignames de Madagascar, dans le contexte`est pourquoi, dans le cadre du programme FADES visant à valoriser les ignames endémiques de Madagascar, nous

Paris-Sud XI, Université de

116

Phylogeography, systematics and conservation status of boid snakes from Madagascar SALAMANDRA, Rheinbach, 39(3/4), 2003  

E-print Network

181 Phylogeography, systematics and conservation status of boid snakes from Madagascar SALAMANDRA of boid snakes from Madagascar (Sanzinia and Acrantophis) MIGUEL VENCES &FRANK GLAW Abstract To assess region (including Nosy Be) and probably Montagne des Français in northern Madagascar, while

117

A link between low-frequency mesoscale eddy variability around Madagascar and the large-scale Indian Ocean variability  

E-print Network

A link between low-frequency mesoscale eddy variability around Madagascar and the large to exist between the mesoscale eddy activity around Madagascar and the large-scale interannual variability­ 2003. The SSH-fields in the Mozambique Channel and east of Madagascar exhibit a significant interannual

van Leeuwen, Peter Jan

118

DONNES SUR LA RPARTITION GOGRAPHIQUE DU GENRE RAVENALA ET SUR SON RLE DANS LA DYNAMIQUE FORESTIRE MADAGASCAR  

E-print Network

FORESTI?RE ? MADAGASCAR Annette HLADIK 1 , Patrick BLANC 2 , Nicolas DUMETZ 3 , Vololoniaina JEANNODA 4'Antananarivo, Faculté des Sciences, Laboratoire de Botanique. B.P. 106, Antananarivo 101, MADAGASCAR : e-mail : precoimd@bow.dts.mg ABSTRACT.- Ravenala is a common plant in the open man-managed lanscape of the humid zone of Madagascar

Paris-Sud XI, Université de

119

QUARTLY ET AL (2006) J. Marine Systems (accepted) page 1 Eddies around Madagascar --the retroflection re-considered  

E-print Network

QUARTLY ET AL (2006) J. Marine Systems (accepted) page 1 Eddies around Madagascar and east of Madagascar, which provides some of the source waters of the Agulhas Current, and examines of variability along the axis of the East Madagascar Current (EMC) and along a zonal band near 25°S. Sequences

Quartly, Graham

120

MADAGASCAR CONSERVATION & DEVELOPMENT VOLUME 4 | ISSUE 1 --JUNE 2009 PAGE 13 Preserving Earth's biodiversity is one of the central chal-  

E-print Network

MADAGASCAR CONSERVATION & DEVELOPMENT VOLUME 4 | ISSUE 1 -- JUNE 2009 PAGE 13 ABSTRACT Preserving advances in understanding human agency in land change in Madagascar in order to synthesize lessons learned agency in land change in Madagascar should enable them to better contribute to the formulation of policy

121

Clich pris en 1905 prsentant des eucalyptus plants en haie autour de la prison de Tamatave, Madagascar.  

E-print Network

, Madagascar. Photo FTM (Foiben-Taosarintanin'i Madagasikara). Daniel Verhaegen1 Honoré Randrianjafy2 Pierre, Antananarivo Madagascar 3 Cirad Upr Bsef Biens et services des écosystèmes forestiers tropicaux 34398 Montpellier Cedex 5 France 4 Cirad Urp Forêts et biodiversité BP 853, Antananarivo Madagascar Historique de l

Boyer, Edmond

122

La Scurisation Foncire Relative dans le contexte de rforme foncire Madagascar : le cas du kijana de Berinrinina  

E-print Network

1 La Sécurisation Foncière Relative dans le contexte de réforme foncière à Madagascar : le cas du Recherches en Partenariat Forêts et Biodiversité. Antananarivo. Madagascar. Ravelona MAAFAKA, département Développement, Centre National de la Recherche Appliquée au Développement Rural. Antananarivo. Madagascar

Paris-Sud XI, Université de

123

n the mid-altitude zones of Madagascar, cropping systems based on direct seeding, with a cover crop  

E-print Network

I n the mid-altitude zones of Madagascar, cropping systems based on direct seeding, with a cover partners in Madagascar have developed modelling tools to monitor and assess activities through a DSS mulch-based cropping systems in Madagascar Developing a learning approach Field visit and assessment

Paris-Sud XI, Université de

124

Evaluation quantitative de la mise en oeuvre de la loi GELOSE : Recensement des TG dans 13 Rgions de Madagascar  

E-print Network

de Madagascar Alexio LOHANIVO Collaborateur auprès de la DGF-DVRN et Doctorant à l administratives de Madagascar : 896 contrats de transferts de gestion signés ont été recensés, parmi lesquels 196 restantes afin de couvrir l'ensemble du territoire de Madagascar. En effet, ces informations, non

Paris-Sud XI, Université de

125

Cartographie participative pour le dveloppement local et la gestion de l'environnement Madagascar : Empowerment, imprialisme numrique ou  

E-print Network

Madagascar : Empowerment, impérialisme numérique ou illusion participative ? Participative cartography for local development and natural resources management in Madagascar: Empowerment, digital imperialism Madagascar à partir d'une méthodologie empruntée à la fois à l'évaluation de la participation citoyenne et à

Paris-Sud XI, Université de

126

Vers de nouvelles interactions entre les Suds ? L'exemple des liens entre Madagascar et l'Afrique du Sud  

E-print Network

1 Vers de nouvelles interactions entre les Suds ? L'exemple des liens entre Madagascar et l du continent, et le pays pauvre voisin, Madagascar, s'inscrivent dans cette dynamique. L'article examine l'intérêt sud-africain pour Madagascar à l'échelle du continent africain et dans le contexte de

Paris-Sud XI, Université de

127

Survey of Giardia and Cryptosporidium in lemurs from the Ranomafana National Park, Madagascar.  

PubMed

We detected Cryptosporidium sp. by direct immunofluorescence in fecal samples from greater bamboo lemurs (Prolemur simus) and eastern rufous mouse lemurs (Microcebus rufus) inhabiting the Ranomafana National Park, Madagascar. This is the first report of an occurrence of these potentially zoonotic parasites in free-ranging lemurs in the rain forest of Madagascar. PMID:23778635

Rasambainarivo, Fidisoa T; Gillespie, Thomas R; Wright, Patricia C; Arsenault, Julie; Villeneuve, Alain; Lair, Stphane

2013-07-01

128

Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts  

ERIC Educational Resources Information Center

The Madagascar hissing cockroach ("Gromphadorhina portentosa") is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach

Wagler, Ron

2009-01-01

129

Antimicrobial resistance among uropathogens that cause community-acquired urinary tract infections in Antananarivo, Madagascar  

Microsoft Academic Search

Background: Urinary tract pathogens obtained from patients in Madagascar are becoming increasingly resistant to commonly used antibiotics that are readily available at a low price. This poses a real problem for the treatment of community-acquired urinary tract infections (UTIs) in Madagascar. Objectives: To obtain data on the pathogens responsible for community-acquired UTIs in Antananarivo and on their susceptibility patterns to

Frederique Randrianirina; Jean-Louis Soares; Jean-Francois Carod; Vincent Thonnier; Antoine Talarmin

130

Broken forest: Applying the integrated conservation and development paradigm to Madagascar's protected areas  

SciTech Connect

The destruction of Madagascar's primary forests through agricultural clearing poses a grave threat to the island's biodiversity. The report assesses the potential of the planned Sustainable and Viable Environmental Management (SAVEM) Project to minimize this threat by implementing Integrated Conservation Development Projects (ICDP's), which link resource conservation to income-generating activities, in the peripheral zones of Madagascar's protected areas.

Barbour, R.; Rabezandria, R.; Daviesson, R.; Guyton, W.; Rakotobe.

1992-06-01

131

Ecological Modelling 185 (2005) 105131 Tropical deforestation in Madagascar: analysis using hierarchical,  

E-print Network

Ecological Modelling 185 (2005) 105­131 Tropical deforestation in Madagascar: analysis using­effect relationships for deforestation at various scales has proven difficult even when rates of deforestation appear approach to develop a novel deforestation model for the eastern wet forested zone of Madagascar, a global

Silander Jr., John A.

132

Deforestation history of the eastern rain forests of Madagascar from satellite images  

Microsoft Academic Search

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain

G. M. Green; R. W. Sussman

1990-01-01

133

Sustainable livelihoods and forest resources in Madagascar: a multi-scale analysis using remote sensing  

Microsoft Academic Search

Madagascar, as much of sub-Saharan Africa, suffers from highly variable and unpredictable climate, and human societies, as well as the natural ecosystems upon which they depend, have evolved and adapted to cope with this to some degree since humans populated the island some 2000 years BP. In Madagascar, humans are an integral component of most landscapes and, thus, may be

Terence P. Dawson; J. Carter Ingram

2008-01-01

134

Conus pennaceus from Madagascar - a complex of geographical subspecies (Gastropoda: Conidae)  

Microsoft Academic Search

Summary Two previously unnamed subspecies of Conus pennaceus Born, 1778 (Gastropoda: Co- nidae) from S Madagascar are described and compared to further geographical subspecies and populations of Conus pennaceus from the S Madagascan area as well as from the E African coast. The marine surface currents around Madagascar are supposed to play an important role in producing genetic isolation between

Werner Korn; Hans-Jrg Niederhfer; Manfred Blcher

135

Lower and Middle Cenomanian ammonites from the Morondava Basin, Madagascar  

NASA Astrophysics Data System (ADS)

Kennedy, W.J., Walaszczyk, I., Gale, A.S., Dembicz, K. and Praszkier, T. 2013. Lower and Midle Cenomanian ammonites from the Morondava Basin, Madagascar. Acta Geologica Polonica, 63(4), 625-655. Warszawa. Lower and Middle Cenomanian ammonite assemblages have been collected on a bed-by-bed basis from localities at Vohipaly and Mahaboboka, Madagascar, as well as from outcrops around Berekata, all in the Morondava Basin, southwest Madagascar. These collections demonstrate the presence of the upper Lower Cenomanian Mantelliceras dixoni Zone and the lower Middle Cenomanian Cunningtoniceras inerme Zone of the north-western European standard sequence. These records indicate that the striking anomalies in the zonal assemblages of the classic divisions of the Madagascan Cenomanian are based on mixed assemblages, rather than a succession that differs radically from that elsewhere in the world. The dixoni Zone fauna is: Desmoceras cf. latidorsatum (Michelin, 1838), Pachydesmoceras kossmati Matsumoto, 1987, Forbesiceras sp., F. baylissiWright & Kennedy, 1984, F. largilliertianum (d'Orbigny, 1841), Mantelliceras cantianum Spath, 1926a, M. dixoni Spath, 1926b, M. mantelli (J. Sowerby, 1814), M. picteti Hyatt, 1903, M. saxbii (Sharpe, 1857), Sharpeiceras sp., S. falloti (Collignon, 1931), S. mocambiquense (Choffat, 1903), S. cf. florencae Spath, 1925, Acompsoceras renevieri (Sharpe, 1857), A. tenue Collignon, 1964, Calycoceras sp., Mrhiliceras lapparenti (Pervinquire, 1907), Mariella (Mariella) stolizcai (Collignon, 1964), Hypoturrilites taxyfabreae (Collignon, 1964), Turrilites scheuchzerianus Bosc, 1801, Sciponoceras cucullatum Collignon, 1964, and Sciponoceras antanimangaensis (Collignon, 1964). The presence of Calycoceras in a Lower Cenomanian association represents a precocious appearance of a genus typically Middle and Upper Cenomanian in occurrence, and matches records from Tunisia. The inerme Zone yields a more restricted assemblage: Pachydesmoceras kossmati, Forbesiceras baylissi, Acanthoceras sp. juv., Cunningtoniceras cunningtoni (Sharpe, 1855) and Hypoturrilites taxyfabreae.

Kennedy, William James; Walaszczyk, Ireneusz; Gale, Andrew S.; Dembicz, Krzysztof; Praszkier, Tomasz

2013-12-01

136

Les aspergillomes pulmonaires: propos de 37 cas Madagascar  

PubMed Central

L'aspergillome pulmonaire est une colonisation par Aspergillus d'une cavit pulmonaire prforme. Nos objectifs taient de dfinir le profil pidmio-clinique et thrapeutique des aspergillomes pulmonaires et essayer de dgager les facteurs favorisants de cette affection Madagascar. Nous avons raliss une tude prospective, descriptive, analytique durant 59 mois sur les aspergillomes pulmonaires Antananarivo Madagascar. Etaient inclus dans cette tude les malades ayant un diagnostic d'aspergillome pulmonaire. Trente-sept (37) cas d'aspergillome pulmonaire taient recenss parmi les 8 392 patients hospitaliss dans le service de Pneumologie (0,44%). Il s'agit de 29 hommes (78,38%) et 8 femmes (21,61%), dge moyen de 43 ans. Les facteurs prdisposant taient domins par la tuberculose pulmonaire (89,19%). Le dlai moyen d'apparition de l'aspergillome chez les malades ayant un antcdent de tuberculose pulmonaire bacilloscopie positive (TPM+) tait de 8 ans et 6 mois avec un dlai extrme de un mois 23 ans. L'hmoptysie tait le mode de rvlation le plus frquent (91,89%). Le traitement tait mdical chez 27 patients (72,97%) et mdico-chirurgical chez 10 patients (27,03%). Vingt sept patients taient perdus de vue (72,97%), et pour les 10 patients suivis (27,02%), 70% avaient une volution favorable avec disparition des signes, et 30% prsentaient des hmoptysies rcidivantes. Le taux de mortalit postopratoire tait de 4% et 50% des patients avaient des complications postopratoires. La surveillance des lsions squellaires de tuberculose pulmonaire qui constituent les facteurs favorisants prdominant d'aspergillome pulmonaire Madagascar ncessite une attention particulire. La prise en charge de la tuberculose doit tre prcoce et adapte surtout dans les pays forte prvalence tuberculeuse. PMID:22187586

Rakotoson, Jolson Lovaniaina; Razafindramaro, Notahiana; Rakotomizao, Jocelyn Robert; Vololontiana, Hanta Marie Danielle; Andrianasolo, Radonirina Lazasoa; Ravahatra, Kiady; Tiaray, Michel; Rajaoarifetra, Jobeline; Rakotoharivelo, Hendriniaina; Andrianarisoa, Ange Christophe Flix

2011-01-01

137

Geological evolution of the Neoproterozoic Bemarivo Belt, northern Madagascar  

USGS Publications Warehouse

The broadly east-west trending, Late Neoproterozoic Bemarivo Belt in northern Madagascar has been re-surveyed at 1:100 000 scale as part of a large multi-disciplinary World Bank-sponsored project. The work included acquisition of 14 U-Pb zircon dates and whole-rock major and trace element geochemical data of representative rocks. The belt has previously been modelled as a juvenile Neoproterozoic arc and our findings broadly support that model. The integrated datasets indicate that the Bemarivo Belt is separated by a major ductile shear zone into northern and southern "terranes", each with different lithostratigraphy and ages. However, both formed as Neoproterozoic arc/marginal basin assemblages that were translated southwards over the north-south trending domains of "cratonic" Madagascar, during the main collisional phase of the East African Orogeny at ca. 540 Ma. The older, southern terrane consists of a sequence of high-grade paragneisses (Sahantaha Group), which were derived from a Palaeoproterozoic source and formed a marginal sequence to the Archaean cratons to the south. These rocks are intruded by an extensive suite of arc-generated metamorphosed plutonic rocks, known as the Antsirabe Nord Suite. Four samples from this suite yielded U-Pb SHRIMP ages at ca. 750 Ma. The northern terrane consists of three groups of metamorphosed supracrustal rocks, including a possible Archaean sequence (Betsiaka Group: maximum depositional age approximately 2477 Ma) and two volcano-sedimentary sequences (high-grade Milanoa Group: maximum depositional age approximately 750 Ma; low grade Daraina Group: extrusive age = 720-740 Ma). These supracrustal rocks are intruded by another suite of arc-generated metamorphosed plutonic rocks, known as the Manambato Suite, 4 samples of which gave U-Pb SHRIMP ages between 705 and 718 Ma. Whole-rock geochemical data confirm the calc-alkaline, arc-related nature of the plutonic rocks. The volcanic rocks of the Daraina and Milanoa groups also show characteristics of arc-related magmatism, but include both calc-alkaline and tholeiitic compositions. It is not certain when the two Bemarivo terranes were juxtaposed, but ages from metamorphic rims on zircon suggest that both the northern and southern terranes were accreted to the northern cratonic margin of Madagascar at about 540-530 Ma. Terrane accretion included the assembly of the Archaean Antongil and Antananarivo cratons and the high-grade Neoproterozoic Anaboriana Belt. Late- to post-tectonic granitoids of the Maevarano Suite, the youngest plutons of which gave ca. 520 Ma ages, intrude all terranes in northern Madagascar showing that terrane accretion was completed by this time. ?? 2009 Natural Environment Research Council (NERC).

Thomas, R.J.; De Waele, B.; Schofield, D.I.; Goodenough, K.M.; Horstwood, M.; Tucker, R.; Bauer, W.; Annells, R.; Howard, K. J.; Walsh, G.; Rabarimanana, M.; Rafahatelo, J.-M.; Ralison, A.V.; Randriamananjara, T.

2009-01-01

138

Proterozoic tectonostratigraphy and paleogeography of central Madagascar derived from detrital zircon U-Pb age populations  

USGS Publications Warehouse

Detrital zircon U-Pb ages determined by SHRIMP distinguish two clastic sequences among Proterozoic metasedimentary rocks from central Madagascar. The Itremo Group is older: zircon data, stromatolite characteristics, and carbon isotope data all point to a depositional age around 1500-1700 Ma. The Molo Group is younger, deposited between ???620 Ma (the age of the youngest zircon) and ???560 Ma (the age of metamorphic overgrowths on detrital cores). Geochronologic provenance analysis of the Itremo Group points to sources in East Africa as well as local sources in central and southern Madagascar but provides no evidence for a detrital contribution from northern and eastern Madagascar nor from southern India. Detrital zircon and sedimentologic similarities between rocks of the Itremo Group and the Zambian Muva Supergroup suggest a lithostratigraphic correlation between the two. The Molo Group has a strong 1000-1100 Ma detrital signature that also indicates an east African provenance and suggests a Neoproterozoic geographic connection with Sri Lanka but shows no indication of input from the Dharwar craton and eastern Madagascar. Central Madagascar was probably juxtaposed with the Tanzanian craton in the Paleo- and Mesoproterozoic, whereas northern and eastern Madagascar were connected to India. Internal assembly of Madagascar postdates Neoproterozoic Molo Group sedimentation and is likely to have occurred at about 560 Ma. ?? 2004 by The University of Chicago. All rights reserved.

Cox, R.; Coleman, D.S.; Chokel, C.B.; DeOreo, S.B.; Wooden, J.L.; Collins, A.S.; De Waele, B.; Kroner, A.

2004-01-01

139

Mangrove forest distributions and dynamics in Madagascar (1975-2005)  

USGS Publications Warehouse

Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ?? one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ???2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km 2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%). ?? 2008 by MDPI.

Giri, C.; Muhlhausen, J.

2008-01-01

140

Mangrove Forest Distributions and Dynamics in Madagascar (19752005)  

PubMed Central

Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ?2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%).

Giri, Chandra; Muhlhausen, Joseph

2008-01-01

141

STUDY OF LAND USE ISSUES CHARACTERIZING THE AMBALAVAO-ANDRINGITRA REGION OF MADAGASCAR  

EPA Science Inventory

EPA Identifier: GF9500572 Title: Study of Land Use Issues Characterizing the Ambalavao-Andringitra Region of Madagascar Fellow (Principal Investigator): Christian Arthur Kull Institution: University of Colorado EPA Grant Representati...

142

Comprehensive Red List Assessment Reveals Exceptionally High Extinction Risk to Madagascar Palms  

PubMed Central

The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascars protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined with local community engagement are essential for the survival of Madagascars palms. PMID:25075612

Rakotoarinivo, Mijoro; Dransfield, John; Bachman, Steven P.; Moat, Justin; Baker, William J.

2014-01-01

143

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle  

Microsoft Academic Search

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite

JEFF A. JOHNSON; RUTH E. TINGA; MELANIE CULVER; FRANK HAILER

2009-01-01

144

New species of Uropodina from Madagascar (Acari: Mesostigmata).  

PubMed

Seven new species and one new genus of Uropodina are described from Madagascar. The third Afrotropical species of Polyaspis is described (Polyapis (Polyaspis) madagascarensis sp. nov.), with a key to the Afrotropical species of the genus. The first species of Dinychus from the Afrotropical region is described, as Dinychus lepus sp. nov.. An unusual new species of Trichouropoda species is described as Trichouropoda madagascarica sp. nov.. A new genus (Malagana gen. nov.) is described, with type species Malagana rotunda sp. nov.. The genus Pulchellaobovella is recorded from the Afrotropical Region for the first time, on the basis of Pulchellaobovella madagascarica sp. nov., with nomenclatural notes on the genera Pulchellaobovella and Janetiella. Uroobovella graeca Kontschn, 2010 is moved into the genus Pulchellaobovella, as Pulchellaobovella graeca (Kontschn, 2010b) comb. nov. Two new species of Rotundabaloghia (Circobaloghia) are described, Rotundabaloghia (Circobaloghia) ermilovi sp. nov. and Rotundabaloghia (Circobaloghia) kaydani sp. nov. PMID:25543586

Kontschn, Jen?; Star, Josef

2014-01-01

145

Checklist of Fishes from Madagascar Reef, Campeche Bank, Mxico  

PubMed Central

Abstract This study presents the first list of fish species from Madagascar Reef, Campeche Bank, Gulf of Mxico. Field surveys and literature review identified 54 species belonging to 8 orders, 30 families and 43 genera, comprising both conspicuous and cryptic fishes. Species richness was lower at this reef site compared to reefs in the Mexican Caribbean, Veracruz or Tuxpan, but was similar to other reefs in the same region. Species composition was a mixture of species present in all the reef systems of the Mexican Atlantic. Hypoplectrus ecosur was recorded here for the first time in the Gulf of Mexico, Mycteroperca microlepis, Equetus lanceolatus and Chaetodipterus faber were new records for the reefs of the Campeche Bank, Elacatinus xanthiprora was recorded for the second time in Mexico and expanded its known distribution westwards from Alacranes Reef and Sanopus reticulatus, endemic of the Yucatan state, was recorded here for the first time on a reef. PMID:24891834

2014-01-01

146

Violences conjugales Antananarivo (Madagascar): un enjeu de sant publique  

PubMed Central

Introduction La violence conjugale a t tudie dans beaucoup de pays dvelopps mais peu en Afrique subsaharienne. Madagascar est un pays o ce phnomne est peu document. Mthodes En 2007, une enqute sur la violence conjugale Antananarivo (ELVICA) a t mene sur la violence conjugale envers les femmes dans la capitale malgache. ELVICA a interrog 400 femmes en union, de 15 59 ans. Des informations sur les caractristiques dmographiques, socioconomiques des couples ont t collectes ainsi que sur les actes de violences physiques des hommes sur leurs pouses. Lobjectif de cet article est didentifier les facteurs de risques de la violence conjugale grave, celle qui a des consquences sur la sant physique des femmes. Rsultats Trente-cinq pour cent des femmes qui ont dclar avoir subi au moins une forme de violence physique au cours des 12 mois prcdent lenqute. Presque la moiti (46%) des femmes violentes ont dclar avoir dj eu des hmatomes, et environ un quart (23%) des plaies avec saignement. Vingt-deux pour cent ont dj d consulter un mdecin. Parmi les nombreuses variables socioconomiques et dmographiques testes, quelques-unes sont associes positivement au risque de violence conjugale grave: le fait pour une femme dtre en union consensuelle et davoir une activit professionnelle. Il y aussi un lien entre la violence subie et lautonomie des femmes (libert accorde par le mari de travailler, de circuler, de voir sa famille). Conclusion A Madagascar, comme ailleurs, la lutte contre les violences conjugales est un lment majeur de lamlioration du statut et de la sant des femmes. PMID:22514757

Gastineau, Bndicte; Gathier, Lucy

2012-01-01

147

Origin of birefringence in andradite from Arizona, Madagascar, and Iran  

NASA Astrophysics Data System (ADS)

The crystal structure of four birefringent andradite samples (two from Arizona, one from Madagascar, and one from Iran) was refined with the Rietveld method, space group Iaoverline{3} d, and monochromatic synchrotron high-resolution powder X-ray diffraction (HRPXRD) data. Each sample contains an assemblage of three different cubic phases. From the electron-microprobe (EMPA) results, fine-scale intergrowths in the Arizona-2 and Madagascar samples appear homogeneous with nearly identical compositions of {Ca2.99Mg0.01}?3[{{Fe}}_{1.99}^{3 + } {{Mn}}_{0.01}^{3 + }]?2(Si2.95Al0.03 {{Fe}}_{0.02}^{3 + })?3O12, Adr98 (Arizona-2), and Adr97 (Madagascar). Both samples are near-end-member andradite, ideally {Ca3}[{{Fe}}2^{3 + }](Si3)O12, so cation ordering in the X, Y, or Z sites is not possible. Because of the large-scale intergrowths, the Arizona-1 and Iran samples contain three different compositions. Arizona-1 has compositions Adr97 (phase-1), Adr93Grs4 (phase-2), and Adr87Grs11 (phase-3). Iran sample has compositions Adr86Uv12 (phase-1), Adr69Uv30 (phase-2), and Adr76Uv22 (phase-3). The crystal structure of the three phases within each sample was modeled quite well as indicated by the Rietveld refinement statistics of reduced ?2 and overall R ( F 2) values of, respectively, 1.980 and 0.0291 (Arizona-1); 1.091 and 0.0305 (Arizona-2); 1.362 and 0.0231 (Madagascar); and 1.681 and 0.0304 (Iran). The dominant phase for each sample has the following unit-cell parameters () and weight fractions (%): a = 12.06314(1), 51.93(9) (Arizona-1); 12.04889(1), 52.47(1) (Arizona-2); 12.06276(1), 52.21(8) (Madagascar); and 12.05962(2), 63.3(1) (Iran). For these dominant phases, the distances and site occupancy factors ( sofs) in terms of neutral atoms at the Ca(X), Fe(Y), and Si(Z) sites are as follows: = 2.4348, Fe-O = 2.0121(6), Si-O = 1.6508(6) ; Ca( sof) = 0.955(2), Fe( sof) = 0.930(2), and Si( sof) = 0.917(2) (Arizona-1); = 2.4288, Fe-O = 2.0148(7), Si-O = 1.6476(7) ; Ca( sof) = 0.953(2), Fe( sof) = 0.891(2), and Si( sof) = 0.927(2) (Arizona-2); = 2.4319, Fe-O = 2.0220(6), Si-O = 1.6460(6) ; Ca( sof) = 0.955(2), Fe( sof) = 0.941(2), and Si( sof) = 0.939(2) (Madagascar); and = 2.4344, Fe-O = 2.0156(8), Si-O = 1.6468(8) ; Ca( sof) = 0.928(2), Fe( sof) = 0.908(2), and Si( sof) = 0.932(3) (Iran). The sofs based on the EMPA results are similar to those obtained from the Rietveld refinement. Each phase in the HRPXRD results can be correlated with a specific chemical composition. For example, the Iran sample composition Adr63Uv30 corresponds to phase-3 that has the smallest unit-cell parameter; Adr76Uv22 corresponds to phase-1 that has the intermediate cell value; and Adr86Uv13 corresponds to phase-2 that has the largest unit-cell parameter. The bond distances compare well with those obtained from radii sum. The three different cubic phases in each sample cause strain that arises from the mismatch of the cubic unit-cell parameters and give rise to birefringence.

Antao, Sytle M.; Klincker, Allison M.

2013-07-01

148

LOGICA VAN INTERACTIE, OF: DE SPEELSE GEEST VAN DE MENS Het nationale bordspel van Madagascar is "Fanorona". Spelers benaderen om de beurt  

E-print Network

1 LOGICA VAN INTERACTIE, OF: DE SPEELSE GEEST VAN DE MENS Het nationale bordspel van Madagascar plaats in een andere puzzel, de vraag naar de geschiedenis van de inwoners van Madagascar. Hun taal, het

van Benthem, Johan

149

Ref. CoP16 Prop. 63 Inclusion of the genus Dalbergia (populations of Madagascar) in Appendix II, and limited to logs, sawn wood and veneer sheets by  

E-print Network

Ref. CoP16 Prop. 63 1 Inclusion of the genus Dalbergia (populations of Madagascar) in Appendix II, and limited to logs, sawn wood and veneer sheets by an annotation Proponent: Madagascar Summary: Dalbergia species of Dalbergia in Madagascar, 47 of which are endemic and some of which produce rosewood. Malagasy

Brown, Jason

150

Primate Conservation 2008 (23): 517 Abstract: Prolemur simus (the greater bamboo lemur) is the most abundant lemur in the northern subfossil sites of Madagascar.  

E-print Network

) is the most abundant lemur in the northern subfossil sites of Madagascar. Living populations still persist the past twenty years scientists have searched the south- and central-eastern rain forests of Madagascar, Ranomafana National Park, Madagascar, Mahasoa, Torotorofotsy The Crisis of the Critically Endangered Greater

Lehman, Shawn M.

151

\\Piversite et Endemisme a Madagascar pp : 243-248 Aoitt 2000 ISBN2-903700-04-4 \\ CURRENT COUNTS OF SPECIES DIVERSITY AND ENDEMISM OF  

E-print Network

\\Piversite et Endemisme a Madagascar pp : 243-248 Aoitt 2000 ISBN2-903700-04-4 \\ CURRENT COUNTS herpetofauna. From 1990-1999 more new species of amphibians and reptiles were described from Madagascar than.6%) endemic to Madagascar itself and 314 (94.3%) to the Malagasy region; 182 described and valid amphibian

152

23. Le contexte juridique des politiques foncires et de dcentralisation pour la gestion des ressources naturelles renouvelables (Approche compare Madagascar/Niger)  

E-print Network

ressources naturelles renouvelables (Approche comparée Madagascar/Niger) Sigrid AUBERT, Abdou TCHOUSSO, Jules RAZAFIARIJAONA Résumé Au Niger comme à Madagascar, la gestion décentralisée des ressources naturelles ne peut, tant au Niger qu'à Madagascar. Les ressources naturelles renouvelables s'inscrivent dans des espaces

Boyer, Edmond

153

Global warming and extinction risks for amphibians in Madagascar, an Franco Andreone, Museo Regionale di Scienze Naturali and Amphibian Specialist Group /  

E-print Network

Global warming and extinction risks for amphibians in Madagascar, an overview Franco Andreone, Museo Regionale di Scienze Naturali and Amphibian Specialist Group / Madagascar, Via G. Giolitti, 36, I.andreone@gmail.com The amphibians of Madagascar represent one of the most extraordinary biodiversity off- shots, with around 240

Andreone, Franco

154

Presence of the Amphibian Chytrid Fungus Batrachochytrium dendrobatidis in Native Amphibians Exported from Madagascar  

PubMed Central

The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

Kolby, Jonathan E.

2014-01-01

155

Why is Madagascar special? The extraordinarily slow evolution of pelican spiders (Araneae, Archaeidae).  

PubMed

Although Madagascar is an ancient fragment of Gondwana, the majority of taxa studied thus far appear to have reached the island through dispersal from Cenozoic times. Ancient lineages may have experienced a different history compared to more recent Cenozoic arrivals, as such lineages would have encountered geoclimatic shifts over an extended time period. The motivation for this study was to unravel the signature of diversification in an ancient lineage by comparing an area known for major geoclimatic upheavals (Madagascar) versus other areas where the environment has been relatively stable. Archaeid spiders are an ancient paleoendemic group with unusual predatory behaviors and spectacular trophic morphology that likely have been on Madagascar since its isolation. We examined disparities between Madagascan archaeids and their non-Madagascan relatives regarding timing of divergence, rates of trait evolution, and distribution patterns. Results reveal an increased rate of adaptive trait diversification in Madagascan archaeids. Furthermore, geoclimatic events in Madagascar over long periods of time may have facilitated high species richness due to montane refugia and stability, rainforest refugia, and also ecogeographic shifts, allowing for the accumulation of adaptive traits. This research suggests that time alone, coupled with more ancient geoclimatic events allowed for the different patterns in Madagascar. PMID:25491087

Wood, Hannah M; Gillespie, Rosemary G; Griswold, Charles E; Wainwright, Peter C

2015-02-01

156

Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.  

PubMed

The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

Kolby, Jonathan E

2014-01-01

157

The odd man out in Sub-Saharan Africa: understanding the tobacco use prevalence in Madagascar  

PubMed Central

Background The tobacco industry has globalized and tobacco use continues to increase in low- and middle-income countries. Yet, the data and research to inform policy initiatives for addressing this phenomenon is sparse. This study aims to estimate the prevalence of adult tobacco use in 17 Sub-Saharan Africa (SSA) countries, and to identify key factors associated with adult tobacco consumption choices (smoked, smokeless tobacco and dual use) in Madagascar. Methods We used Demographic Health Survey for estimating tobacco use prevalence among adults in SSA. A multinomial logistic regression model was used to identify key determinants of adult tobacco consumption choices in Madagascar. Results While differences in tobacco use exist in SSA, Madagascar has exceptionally higher prevalence rates (48.9% of males; 10.3% of females). The regression analyses showed complexity of tobacco use in Madagascar and identified age, education, wealth, employment, marriage, religion and place of residence as factors significantly associated with the choice of tobacco use among males, while age, wealth, and employment were significantly associated with that of females. The effects, however, differ across the three choices of tobacco use compared to non-use. Conclusions Tobacco use in Madagascar was higher than the other 16 SSA countries. Although the government continues to enact policies to address the problem, there is a need for effective implementation and enforcement. There is also the need for health education to modify social norms and denormalize tobacco use. PMID:24044737

2013-01-01

158

Did lemurs have sweepstake tickets? An exploration of Simpson's model for the colonization of Madagascar by mammals  

Microsoft Academic Search

Aim To investigate the validity of Simpson's model of sweepstakes dispersal, particularly as it applies to the colonization of Madagascar by African mammals. We chose lemurs as a classic case. Location The East African coast, the Mozambique Channel and Madagascar. Methods First, we investigated the assumptions underlying Simpson's statistical model as it relates to dispersal events. Second, we modelled the

J. Stankiewicz; C. Thiart; J. C. Masters; M. J. De Wit

2006-01-01

159

Discovery of three new fungal species from dying Baobab trees in South Africa and Madagascar Prepared by Elsie Cruywagen  

E-print Network

Discovery of three new fungal species from dying Baobab trees in South Africa and Madagascar Prepared by Elsie Cruywagen Baobab trees are iconic plants that represent some of the most recognisable trees in the world. The eight known species of baobab belong to a single genus, Adansonia. Madagascar

160

Asynchronous colonization of Madagascar by the four endemic clades of primates, tenrecs, carnivores, and rodents as inferred from nuclear genes  

Microsoft Academic Search

Madagascar harbors four large adaptive radiations of endemic terrestrial mammals: lemurs, tenrecs, carnivorans, and rodents. These rank among the most spectacular examples of evolutionary diversification, but their monophyly and origins are debated. The lack of Tertiary fossils from Madagascar leaves molecular studies as most promising to solve these controversies. We provide a simultaneous reconstruction of phylogeny and age of the

Celine Poux; Ole Madsen; Elisabeth Marquard; D. Rodriguez Vieites; WILFRIED W. DE JONG; Miguel Vences

2005-01-01

161

Maternal health practices, beliefs and traditions in southeast Madagascar.  

PubMed

Contextualising maternal health in countries with high maternal mortality is vital for designing and implementing effective health interventions. A research project was therefore conducted to explore practices, beliefs and traditions around pregnancy, delivery and postpartum in southeast Madagascar. Interviews and focus groups were conducted with 256 pregnant women, mothers of young children, community members and stakeholders; transcripts were analysed to identify and explore predetermined and emerging themes. A questionnaire was also conducted with 373 women of reproductive age from randomly selected households. Data was analysed using STATA. Results confirmed high local rates of maternal mortality and morbidity and revealed a range of traditional health care practices and beliefs impacting on women's health seeking behaviours. The following socio-cultural barriers to health were identified: 1) lack of knowledge, 2) risky practices, 3) delays seeking biomedical care, and 4) family and community expectations. Recommendations include educational outreach and behaviour change communications targeted for women, their partners and family, increased engagement with traditional midwives and healers, and capacity building of formal health service providers. PMID:25438515

Morris, Jessica L; Short, Samm; Robson, Laura; Andriatsihosena, Mamy Soafaly

2014-09-01

162

Bioactive compounds from Stuhlmannia moavi from the Madagascar dry forest?  

PubMed Central

Bioassay-directed fractionation of the leaf and root extracts of the antiproliferative Madagascar plant Stuhlmannia moavi afforded 6-acetyl-5,8-dihydroxy-2-methoxy-7-methyl-1,4-naphthoquinone (stuhlmoavin, 1) as the most active compound, with an IC50 value of 8.1 M against the A2780 human ovarian cancer cell line, as well as the known homoisoflavonoid bonducellin (2) and the stilbenoids 3,4,5'-trihydroxy-3'-methoxy-trans-stilbene (3), piceatannol (4), resveratrol (5), rhapontigenin (6), and isorhapontigenin (7). The structure elucidation of all compounds was based on NMR and mass spectroscopic data, and the structure of 1 was confirmed by a single crystal X-ray analysis. Compounds 25 showed weak A2780 activities, with IC50 values of 10.6, 54.0, 41.0, and 74.0 M, respectively. Compounds 13 also showed weak antimalarial activity against Plasmodium falciparum with IC50 values of 23, 26, and 27 M, respectively. PMID:24239390

Liu, Yixi; Harinantenaina, Liva; Brodie, Peggy J.; Bowman, Jessica D.; Cassera, Maria B.; Slebodnick, Carla; Callmander, Martin W.; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E.; Applequist, Wendy; Birkinshaw, Chris; Lewis, Gwilym P.; Kingston, David G. I.

2013-01-01

163

Insatiable demands: Income, energy and environmental policy in Madagascar  

SciTech Connect

The island nation of Madagascar is suffering the collision of three distinct trends: economic stagnation, a rapidly expanding population and a severely threatened natural resource base. Demands for growth, new energy reserves and environmental conservation, especially of forest resources, are creating a policy dilemma for both government officials and donors. This study seeks to bring new evidence to bear on this policy dilemma. Primary data on urban household income, family size and consumption of various energy types are used to test two main hypothesis (1) that charcoal, which constitutes the fuel of choice for a vast majority of the sample, is a normal rather than an inferior good, and (2) that demand for wood-fuels constitutes a genuine threat to the viability of the forest resource. The data indicate that income elasticities of demand for charcoal are positive over a broad range of per capita income levels, revealing that charcoal is, indeed a normal good for a large portion of the population represented by the sample. A model of forest degradation is built which establishes a clear link between wood-fuel demand and forest degradation. Together, these findings make clear that under current income patterns, and for the forseeable future, charcoal is a normal good and its consumption by urban residents constitutes a serious threat to the natural forest resource. The study concludes with a policy analysis which identifies existing market failures due to government policies and recommends changes based on tested policy prescriptions in other parts of the developing world.

Shaw, C.L.

1993-01-01

164

Maternal health practices, beliefs and traditions in southeast Madagascar.  

PubMed

Contextualising maternal health in countries with high maternal mortality is vital for designing and implementing effective health interventions. A research project was therefore conducted to explore practices, beliefs and traditions around pregnancy, delivery and postpartum in southeast Madagascar. Interviews and focus groups were conducted with 256 pregnant women, mothers of young children, community members and stakeholders; transcripts were analysed to identify and explore predetermined and emerging themes. A questionnaire was also conducted with 373 women of reproductive age from randomly selected households. Data was analysed using STATA. Results confirmed high local rates of maternal mortality and morbidity and revealed a range of traditional health care practices and beliefs impacting on women's health seeking behaviours. The following socio-cultural barriers to health were identified: 1) lack of knowledge, 2) risky practices, 3) delays seeking biomedical care, and 4) family and community expectations. Recommendations include educational outreach and behaviour change communications targeted for women, their partners and family, increased engagement with traditional midwives and healers, and capacity building of formal health service providers. PMID:25508046

Morris, Jessica L; Short, Samm; Robson, Laura; Andriatsihosena, Mamy Soafaly

2014-09-01

165

Seroepidemiology of human plague in the Madagascar highlands.  

PubMed

We conducted a seroepidemiological survey of human plague in the general population using random sampling in the area of Ambositra, the main focus of plague in the central highlands of Madagascar (520 confirmed and presumptive cases notified during the past 10 years). Sera were tested using an ELISA IgG F1 assay. Considering the internal validity of the assay and the sampling method, the overall corrected prevalence of F1 antibodies was 0.6% (95% CI: 0.2%-1.8%). Being nearly 0 up to the age of 40, the corrected prevalence increased markedly after 45 years to 6.2%. Six of 20 individuals who declared to have been treated for clinical suspicion of bubonic plague in the past had F1 antibodies. The seroprevalence did not differ according to gender except in individuals > 60, where antibodies were significantly more frequent in males. This study suggests that the number of clinically suspected cases of plague provided by the surveillance network was plausible, despite some true cases being missed and a significant number of false positives. We also confirm that Yersinia pestis infections may occur without marked clinical manifestations and patients may recover without treatment, in accordance with old observations of pestis minor. PMID:10747268

Ratsitorahina, M; Rabarijaona, L; Chanteau, S; Boisier, P

2000-02-01

166

Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar  

PubMed Central

We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300?bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages. PMID:16096096

Monaghan, Michael T; Gattolliat, Jean-Luc; Sartori, Michel; Elouard, Jean-Marc; James, Helen; Derleth, Pascale; Glaizot, Olivier; de Moor, Ferdy; Vogler, Alfried P

2005-01-01

167

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle  

USGS Publications Warehouse

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. ?? 2008 The Authors.

Johnson, J.A.; Tingay, R.E.; Culver, M.; Hailer, F.; Clarke, M.L.; Mindell, D.P.

2009-01-01

168

Receiver function analysis and preliminary body wave tomography of the MACOMO network in Madagascar  

NASA Astrophysics Data System (ADS)

We present results from a set of seismological studies of the continental island of Madagascar using new seismic data from the NSF-funded MACOMO (MAdagascar, COmores, and MOzambique) IRIS PASSCAL broadband seismometer array. MACOMO involved the deployment during 2011-2013 of 26 broadband seismometers in Madagascar and 6 seismometers in Mozambique, providing the first seismic imaging across the world's 4th-largest island. We present preliminary crustal structure variations from receiver function analyses and body wave tomography results. We calculate radial receiver functions for all Madagascar stations and use the weighted linear regression methodology of Herrmann and Ammon [2002] to invert for shear velocity. Upper mantle and crustal structures from the receiver function analyses are used to help determine starting models for the teleseismic travel-time tomography. The tectonic structure of Madagascar is generally divided into four crustal blocks. Initial seismic imaging shows that the Archean Antongil block that runs along the east of the island has the thickest crust (>40 km) and three Proterozoic terranes that make up the central highlands and are bounded by fault and shear zones are closer to the average crustal thickness (35 km). There has been late Cenozoic intraplate volcanism in northern and central Madagascar (as recently as 1 million years ago), and different hypotheses for its origin will be evaluated by the preliminary results from the three different seismic studies. Complete analyses will be done incorporating seismic data from simultaneous and complementary array of both land- and ocean-based seismometers from French and German deployments.

Pratt, M. J.; Wysession, M. E.; Wiens, D. A.; Nyblade, A.; Aleqabi, G. I.; Shore, P.; Rambolamana, G.; Sy Tanjona Andriampenomanana ny Ony, F.; Rakotondraibe, T.

2013-12-01

169

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle.  

PubMed

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. PMID:19140964

Johnson, Jeff A; Tingay, Ruth E; Culver, Melanie; Hailer, Frank; Clarke, Michle L; Mindell, David P

2009-01-01

170

Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts  

NSDL National Science Digital Library

The Madagascar hissing cockroach gromphadorhina portentosa) is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach students how to properly care for animals, and are very cool looking! This article describes an inquiry-based MHC activity and further questions for your students to explore. The activity and questions address basic concepts of nutrition.

Wagler, Ron

2009-03-01

171

Surveillance and control of rabies in La Reunion, Mayotte, and Madagascar  

PubMed Central

Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities. PMID:24016204

2013-01-01

172

Delimiting Species without Nuclear Monophyly in Madagascar's Mouse Lemurs  

PubMed Central

Background Speciation begins when populations become genetically separated through a substantial reduction in gene flow, and it is at this point that a genetically cohesive set of populations attain the sole property of species: the independent evolution of a population-level lineage. The comprehensive delimitation of species within biodiversity hotspots, regardless of their level of divergence, is important for understanding the factors that drive the diversification of biota and for identifying them as targets for conservation. However, delimiting recently diverged species is challenging due to insufficient time for the differential evolution of charactersincluding morphological differences, reproductive isolation, and gene tree monophylythat are typically used as evidence for separately evolving lineages. Methodology In this study, we assembled multiple lines of evidence from the analysis of mtDNA and nDNA sequence data for the delimitation of a high diversity of cryptically diverged population-level mouse lemur lineages across the island of Madagascar. Our study uses a multi-faceted approach that applies phylogenetic, population genetic, and genealogical analysis for recognizing lineage diversity and presents the most thoroughly sampled species delimitation of mouse lemur ever performed. Conclusions The resolution of a large number of geographically defined clades in the mtDNA gene tree provides strong initial evidence for recognizing a high diversity of population-level lineages in mouse lemurs. We find additional support for lineage recognition in the striking concordance between mtDNA clades and patterns of nuclear population structure. Lineages identified using these two sources of evidence also exhibit patterns of population divergence according to genealogical exclusivity estimates. Mouse lemur lineage diversity is reflected in both a geographically fine-scaled pattern of population divergence within established and geographically widespread taxa, as well as newly resolved patterns of micro-endemism revealed through expanded field sampling into previously poorly and well-sampled regions. PMID:20360988

Weisrock, David W.; Rasoloarison, Rodin M.; Fiorentino, Isabella; Ralison, Jos M.; Goodman, Steven M.; Kappeler, Peter M.; Yoder, Anne D.

2010-01-01

173

Economic valuation of subsistence harvest of wildlife in Madagascar.  

PubMed

Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife's ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha(-1) year(-1). Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people's food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. PMID:24405165

Golden, Christopher D; Bonds, Matthew H; Brashares, Justin S; Rasolofoniaina, B J Rodolph; Kremen, Claire

2014-02-01

174

Climate change and the cost of conserving species in Madagascar.  

PubMed

We examined the cost of conserving species as climate changes. We used a Maxent species distribution model to predict the ranges from 2000 to 2080 of 74 plant species endemic to the forests of Madagascar under 3 climate scenarios. We set a conservation target of achieving 10,000 ha of forest cover for each species and calculated the cost of achieving this target under each scenario. We interviewed managers of projects to restore native forests and conducted a literature review to obtain the net present cost per hectare of management actions to maintain or establish forest cover. For each species, we added hectares of land from lowest to highest cost per additional year of forest cover until the conservation target was achieved throughout the time period. Climate change was predicted to reduce the size of species' ranges, the overlap between species' ranges and existing or planned protected areas, and the overlap between species' ranges and existing forest. As a result, climate change increased the cost of achieving the conservation target by necessitating successively more costly management actions: additional management within existing protected areas (US$0-60/ha); avoidance of forest degradation (i.e., loss of biomass) in community-managed areas ($160-576/ha); avoidance of deforestation in unprotected areas ($252-1069/ha); and establishment of forest on nonforested land within protected areas ($802-2710/ha), in community-managed areas ($962-3226/ha), and in unprotected areas ($1054-3719/ha). Our results suggest that although forest restoration may be required for the conservation of some species as climate changes, it is more cost-effective to maintain existing forest wherever possible. PMID:22497442

Busch, Jonah; Dave, Radhika; Hannah, Lee; Cameron, Alison; Rasolohery, Andriambolantsoa; Roehrdanz, Patrick; Schatz, George

2012-06-01

175

Human and environmental controls over aboveground carbon storage in Madagascar  

PubMed Central

Background Accurate, high-resolution mapping of aboveground carbon density (ACD, Mg C ha-1) could provide insight into human and environmental controls over ecosystem state and functioning, and could support conservation and climate policy development. However, mapping ACD has proven challenging, particularly in spatially complex regions harboring a mosaic of land use activities, or in remote montane areas that are difficult to access and poorly understood ecologically. Using a combination of field measurements, airborne Light Detection and Ranging (LiDAR) and satellite data, we present the first large-scale, high-resolution estimates of aboveground carbon stocks in Madagascar. Results We found that elevation and the fraction of photosynthetic vegetation (PV) cover, analyzed throughout forests of widely varying structure and condition, account for 27-67% of the spatial variation in ACD. This finding facilitated spatial extrapolation of LiDAR-based carbon estimates to a total of 2,372,680 ha using satellite data. Remote, humid sub-montane forests harbored the highest carbon densities, while ACD was suppressed in dry spiny forests and in montane humid ecosystems, as well as in most lowland areas with heightened human activity. Independent of human activity, aboveground carbon stocks were subject to strong physiographic controls expressed through variation in tropical forest canopy structure measured using airborne LiDAR. Conclusions High-resolution mapping of carbon stocks is possible in remote regions, with or without human activity, and thus carbon monitoring can be brought to highly endangered Malagasy forests as a climate-change mitigation and biological conservation strategy. PMID:22289685

2012-01-01

176

Economic Valuation of Subsistence Harvest of Wildlife in Madagascar  

PubMed Central

Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlifes ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha?1 year?1. Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local peoples food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. PMID:24405165

Golden, Christopher D.; Bonds, Matthew H.; Brashares, Justin S.; Rasolofoniaina, B. J. Rodolph; Kremen, Claire

2014-01-01

177

Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat out of Recycled Materials  

ERIC Educational Resources Information Center

Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their "wow" factor. These characteristics make them unique

Wagler, Ron

2010-01-01

178

An endangered new species of edible yam (Dioscorea, Dioscoreaceae) from Western Madagascar and its conservation  

E-print Network

An endangered new species of edible yam (Dioscorea, Dioscoreaceae) from Western Madagascar and its Louis Jeannoda4 , & Claude Marcel Hladik3 Summary. A new species of Dioscorea from Morondava prefecture and is endangered under IUCN Red List category criteria (IUCN 2001). The unusual morphological features of its

Paris-Sud XI, Université de

179

The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes  

E-print Network

ORIGINAL ARTICLE The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes William, Rondebosch 7701, South Africa. E-mail: william.bond@uct.ac.za ABSTRACT Aim Grasslands and savannas, which ­ that the grasslands are an insular example of the post-Miocene spread of C4 grassy biomes world-wide. Location

Silander Jr., John A.

180

Plants traditionally prescribed to treat tazo (malaria) in the eastern region of Madagascar  

Microsoft Academic Search

BACKGROUND: Malaria is known as tazo or tazomoka in local terminology in Madagascar. Within the context of traditional practice, malaria (and\\/or malaria symptoms) is commonly treated by decoctions or infusions from bitter plants. One possible approach to the identification of new antimalarial drug candidates is to search for compounds that cure or prevent malaria in plants empirically used to treat

Milijaona Randrianarivelojosia; Valrie T Rasidimanana; Harison Rabarison; Peter K Cheplogoi; Michel Ratsimbason; Dulcie A Mulholland; Philippe Mauclre

2003-01-01

181

Plant Species Fed on by Lemur catta in Gallery Forests of the Southern Domain of Madagascar  

Microsoft Academic Search

In this paper, we provide an overview of the feeding trends of Lemur catta, the ringtailed lemur, including a checklist of all plant species and plant items known to be ingested by this prosimian species in three different forests of southwestern and southern Madagascar. Ringtailed lemurs have been mainly studied in gallery forests including riverine forest, closed canopy forest, and

Bruno Simmen; MICHELLE L. SAUTHER; Takayo Soma; Hantanirina Rasamimanana; Robert Sussman; Alison Jolly; Laurent Tarnaud; Annette Hladik

182

Description of a new genus and species, Pseudobasidissus barclayi (Coleoptera: Anthribidae), from east Madagascar.  

PubMed

A new genus and species, Pseudobasidissus barclayi Trzna & Ba?a? gen. nov. et sp. nov. (Anthribidae: Anthribinae: Platyrhinini), from Madagascar is described. Male and female genitalia are studied and illustrated. Colour photographs of the holotype and genitalia of both sexes are provided. Comparison is made with the similar genus Basidissus Fairmaire. PMID:25283911

Trzna, Milo; Ba?a?, Petr

2014-01-01

183

DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar  

Microsoft Academic Search

The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a

M. Alex Smith; Brian L. Fisher; Paul D. N. Hebert

2005-01-01

184

Designing the Masoala National Park in Madagascar Based on Biological and Socioeconomic Data  

Microsoft Academic Search

Conservation biologists have developed powerful tools for reserve selection and design over the past two decades, yet seldom are protected areas actually designed on scientific grounds. Using fundamental biological and socioeconomic principles of conservation science, we designed a new protected area and its multiple-use zone on the Masoala Peninsula in the humid forest zone of Madagascar. The explicit design cri-

Claire Kremen; Vincent Razafimahatratra; R. Philip Guillery; Jocelyn Rakotomalala; Andrew Weiss; Jean-Solo Ratsisompatrarivo

1999-01-01

185

Farmers' Welfare and Changing Food Prices: Nonparametric Evidence from Rice in Madagascar  

Microsoft Academic Search

This paper uses nonparametric density estimation and kernel smoothing techniques to examine the instantaneous distributional implications of rice price changes in Madagascar. While many farmers do not participate in product markets as either buyers or sellers, and net sales or marketable surplus are fairly small for many others, the roughly one-third of rice farmers who fall below the poverty line

Christopher B. Barrett; Paul A. Dorosh

1996-01-01

186

Candidatus Phytoplasma malaysianum, a novel taxon associated with virescence and phyllody of Madagascar periwinkle (Catharanthus roseus)  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study addressed the taxonomic position and group classification of a phytoplasma responsible for virescence and phyllody symptoms in naturally diseased Madagascar periwinkle plants in western Malaysia. Unique regions in the 16S rRNA gene from the Malaysian periwinkle virescence (MaPV) phytopla...

187

Determinants of credit rationing: A study of informal lenders and formal credit groups in Madagascar  

Microsoft Academic Search

Previous research on the determinants of credit rationing exclusively focused on thebehavior of formal lenders who contract directly with an individual borrower. Based on ahousehold survey in Madagascar, this paper presents an analysis of credit rationing behaviorby informal lenders and by members of community-based groups that allocate formal grouploans among themselves. The results show that group members obtain and use

Manfred Zeller

1994-01-01

188

THE subfossil occurrence and paleoecological significance of small mammals at ankilitelo cave, southwestern Madagascar  

USGS Publications Warehouse

Small mammals are rarely reported from subfossil sites in Madagascar despite their importance for paleoenvironmental reconstruction, especially as it relates to recent ecological changes on the island. We describe the uniquely rich subfossil small mammal fauna from Ankilitelo Cave, southwestern Madagascar. The Ankilitelo fauna is dated to the late Holocene (???500 years ago), documenting the youngest appearances of the extinct giant lemur taxa Palaeopropithecus, Megaladapis, and Archaeolemur, in association with abundant remains of small vertebrates, including bats, tenrecs, carnivorans, rodents, and primates. The Ankilitelo fauna is composed of 34 mammalian species, making it one of the most diverse Holocene assemblages in Madagascar. The fauna comprises the 1 st report of the short-tailed shrew tenrec (Microgale brevicaudata) and the ring-tailed mongoose (Galidia elegans) in southwestern Madagascar. Further, Ankilitelo documents the presence of southwestern species that are rare or that have greatly restricted ranges today, such as Nasolo's shrew tenrec (M. nasoloi), Grandidier's mongoose (Galidictis grandidieri), the narrow-striped mongoose (Mungotictis decemlineata), and the giant jumping rat (Hypogeomys antimena). A simple cause for the unusual small mammal occurrences at Ankilitelo is not obvious. Synergistic interactions between climate change, recent fragmentation and human-initiated degradation of forested habitats, and community-level processes, such as predation, most likely explain the disjunct distributions of the small mammals documented at Ankilitelo. ?? 2009 American Society of Mammalogists.

Muldoon, K.M.; De Blieux, D. D.; Simons, E.L.; Chatrath, P.S.

2009-01-01

189

Reconciling fossils and molecules: Cenozoic divergence of cichlid fishes and the biogeography of Madagascar  

Microsoft Academic Search

Aim The biogeographical origins of the extant vertebrates endemic to Madagascar are largely unsolved, but have often been related to vicariance in the context of fragmentation of the supercontinent Gondwana in the Mesozoic. Such hypotheses are especially appealing in the case of cichlid fishes, which show phylogenetic relationships reflecting the temporal successions of the breakup of Gondwana. We used molecular

M. Vences; J. Freyhof; R. Sonnenberg; J. Kosuch; M. Veith

2001-01-01

190

Patterns of amphibian and reptile diversity at Berara Forest (Sahamalaza Peninsula), NW Madagascar  

Microsoft Academic Search

Amphibians and reptiles were surveyed at Berara, a forest on the Sahamalaza Peninsula, NW Madagascar. Visual methods and pitfalls were used, leading to the discovery of 12 amphibian and 30 reptile species. The herpetofaunal community appeared as a mosaic of dry forest species and species from the more humid Sambirano Domain. The comparatively low amphibian diversity may be correlated with

Franco Andreone; Miguel Vences; Jasmin Emile Randrianirina

2001-01-01

191

Examining the Environmental Awareness of Children and Adolescents in the Ranomafana Region, Madagascar  

ERIC Educational Resources Information Center

This paper examines children's and adolescents' environmental awareness in rural Madagascar. Two types of school survey among 8- to 21-year-old students and pupils in 18 schools were used for data collection. The objective of this comparative study was to examine the environmental awareness and knowledge of children and adolescents living under

Korhonen, Kaisa; Lappalainen, Anu

2004-01-01

192

Earth structure and instrumental seismicity of Madagascar: Implications on the seismotectonics  

NASA Astrophysics Data System (ADS)

The aim of this study is to improve the knowledge of the seismotectonics of Madagascar. We first investigate the structure of the Earth beneath Madagascar through the joint inversion of receiver functions and Rayleigh wave group velocities. Then we use the obtained velocity models to relocate local earthquakes in order to analyse the distribution of seismicity. Finally, we use structural models and earthquake coordinates to compute focal mechanisms. Our retrieved Earth structure models confirm a thin lithosphere beneath Madagascar when compared to the nearby East African Rift. The High Plateau in the Central region coincides with the thinnest lithosphere over the slowest asthenosphere. Our results are in good agreement with the gravity anomalies and likely confirm a localised asthenospheric upwelling beneath the central part of Madagascar. The surface expression of the asthenospheric upwelling consists in a horst-graben structure. The moderate seismicity is localised along pre-existing structures reflecting an E-W extension that is mostly accommodated in the lower crust.

Rindraharisaona, Elisa Josiane; Guidarelli, Mariangela; Aoudia, Abdlkarim; Rambolamanana, Grard

2013-05-01

193

Population and Territory Stability of the Lemur catta at Berenty, Madagascar  

Microsoft Academic Search

Several Lemur catta troops at Berenty, Madagascar have been censused repeatedly since 1963. In 1972, the entire reserve was censused. A recensus in 1975 showed that although some minor changes have occurred in the number of animals in individual troops, the population of the reserve as a whole, the core areas of the lemurs territories, and their home range boundaries

Anne S. Mertl-Mllhollen; Herbert L. Gustafson; Norman Budnitz; Kathryn Dainis; Alison Jolly

1979-01-01

194

Tectonic framework of the Precambrian of Madagascar and its Gondwana connections: a review and reappraisal  

Microsoft Academic Search

The Precambrian of Madagascar is divided into two sectors by the north-west trending sinistral Ranotsara shear zone, which continues in the Mozambique belt, probably as the Surma shear zone, and in Southern India as the Achankovil shear zone. South of Ranotsara six north-south trending tectonic belts are recognized that consist largely of granulite and high amphibolite facies paragneisses, phlogopite diopsidites,

B. F. Windley; A. Razafiniparany; T. Razakamanana; D. Ackermand

1994-01-01

195

Has Vicariance or Dispersal Been the Predominant Biogeographic Force in Madagascar? Only Time Will Tell  

Microsoft Academic Search

Madagascar is one of the world's hottest biodiversity hot spots due to its diverse, endemic, and highly threatened biota. This biota shows a distinct signature of evolution in isolation, both in the high levels of diversity within lineages and in the imbalance of lineages that are represented. For example, chameleon diversity is the highest of any place on Earth, yet

Anne D. Yoder; Michael D. Nowak

2006-01-01

196

Which Advisory System to Support Innovation in Conservation Agriculture? The Case of Madagascar's Lake Alaotra  

ERIC Educational Resources Information Center

Purpose: To promote sustainable agriculture, various development projects are encouraging farmers around Madagascar's Lake Alaotra to adopt conservation agriculture techniques. This article's objective is to analyze the capacity of a project-funded advisory system to accompany such an innovation and to design and implement an advisory method aimed

Faure, Guy; Penot, Eric; Rakotondravelo, Jean Chrysostome; Ramahatoraka, Haja Andrisoa; Dugue, Patrick; Toillier, Aurelie

2013-01-01

197

Prioritizing key biodiversity areas in Madagascar by including data on human pressure and ecosystem services  

Microsoft Academic Search

Establishment of protected area networks to protect species and habitats has been one of the most effective conservation tools used around the world. On this premise Madagascar is planning to triple its protected areas by 2012. Recent studies have addressed the design of this new network in order to optimize biodiversity conservation. However, given the limited time, available resources and

Heather M. Rogers; Louise Glew; Miroslav Honzk; Malcolm D. Hudson

2010-01-01

198

Genetics of the Pig Tapeworm in Madagascar Reveal a History of Human Dispersal and Colonization  

PubMed Central

An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation. PMID:25329310

Yanagida, Tetsuya; Carod, Jean-Franois; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P.; Ito, Akira

2014-01-01

199

New mapping of kilometric anisotropies over the granulitic continental crust of Madagascar: melt -fluid migration and  

E-print Network

underlined by mineralization of economic interest such as gold and corundum. Primary diffuse gold mineralization is associated with syenites and granites emplaced in the crust. Gold is remobilized deposits of Madagascar: A review. Ore Geology Reviews, 34, 134-154. PGRM: http://www2.gaf.de/BPGRM/ #12;

200

Aligning Conservation Priorities Across Taxa in Madagascar with High-Resolution Planning Tools  

Microsoft Academic Search

Globally, priority areas for biodiversity are relatively well known, yet few detailed plans exist to direct conservation action within them, despite urgent need. Madagascar, like other globally recognized biodiversity hot spots, has complex spatial patterns of endemism that differ among taxonomic groups, creating challenges for the selection of within-country priorities. We show, in an analysis of wide taxonomic and geographic

C. Kremen; A. Cameron; A. Moilanen; S. J. Phillips; C. D. Thomas; H. Beentje; J. Dransfield; B. L. Fisher; F. Glaw; T. C. Good; G. J. Harper; R. J. Hijmans; D. C. Lees; E. Louis; R. A. Nussbaum; C. J. Raxworthy; A. Razafimpahanana; G. E. Schatz; M. Vences; D. R. Vieites; P. C. Wright; M. L. Zjhra

2008-01-01

201

Effects of anthropogenic environmental changes on amphibian diversity in the rain forests of eastern Madagascar  

Microsoft Academic Search

Madagascar has one of the world's highest rates of human population increase, which is coupled with an increase of resource exploitation, particularly food and firewood. Forests are cleared and converted to rice fields or plantations (mainly Eucalyptus or pine). How does deforestation affect the amphibian diversity of the original biotope, the rain forest? To answer this question, the amphibian fauna

Denis Vallan

2002-01-01

202

Phylogenetic relationships of Trachylepis skink species from Madagascar and the Seychelles (Squamata: Scincidae).  

PubMed

Lizards of the genus Trachylepis are a species-rich group of skinks mainly inhabiting Africa, Madagascar, and several other islands in the western Indian Ocean. All except one probably introduced species of Madagascan Trachylepis are endemic. Two species groups have been distinguished on the basis of subocular scale shape but their phylogenetic relationships remained unclear. We inferred a multilocus phylogeny of the Madagascan Trachylepis species, based on a concatenated dataset of 3261 bp from 3 mitochondrial and 4 nuclear genes with a dense Madagascan taxon sampling and find high support for the monophyly of the endemic Madagascan Trachylepis. The two species groups in Madagascar are highly supported as clades. The highland species T. boettgeri is nested in the T. aureopunctata species group of mainly arid-adapted species, suggesting a colonization of highland swamps by ancestors inhabiting dry western Madagascar. The Seychellois species were sister to the T. maculilabris/T. comorensis clade, suggesting their origin directly out of Africa as with Seychellois chameleons. In Madagascar, a high intraspecific molecular variation was confirmed for T. gravenhorstii, T. elegans, and T. vato, indicating a need for taxonomic revision. PMID:23435267

Lima, Alexandra; James Harris, D; Rocha, Sara; Miralles, Aurlien; Glaw, Frank; Vences, Miguel

2013-06-01

203

New material of Dadadon isaloi (Cynodontia, Traversodontidae) from the Triassic of Madagascar  

Microsoft Academic Search

New material of the traversodontid cynodont Dadadon isaloi from the Triassic of southwestern Madagascar is described. The new material consists of a complete, well-preserved skull (FMNH PR 2232) and an unassociated, partial lower jaw (UA 10608). The new material reveals several novel aspects of Dadadon's morphology. Newly recognized autapomorphies that diagnose Dadadon include a fourth upper incisor with posterior accessory

Lovasoa Ranivoharimanana; Christian F. Kammerer; John J. Flynn; Andr R. Wyss

2011-01-01

204

The Hazomanga among the Masikoro of Southwest Madagascar: Identity and History  

Microsoft Academic Search

In this article Masikoro identity is linked to the Sakalava of western and northwestern Madagascar. An analysis that associates two ritual objects, the hazo- manga (a wooden pole symbolizing a lineage, sometimes shaped like a cross, upon which sacrificial blood is consecrated to ones raza or ancestors) and the jiny (an- cestral relics), is presented in support of the Sakalava-Masikoro

Jeanne Dina

2001-01-01

205

The traditional shark fisheries of southwest Madagascar: A study in the Toliara region  

Microsoft Academic Search

Traditional shark fisheries in Africa are largely poorly documented. Fisheries management plans for fisheries targeting chondrichthyan species are typically based on studies with limited spatial resolution or detail, compromising their efficacy and potentially reducing the effectiveness of national and regional plans. Southwest Madagascar is an area poorly documented with regard to many of its marine resources. This study presents a

Angus R. McVean; Ryan C. J. Walker; Eibleis Fanning

2006-01-01

206

Epidemiologic Features of Four Successive Annual Outbreaks of Bubonic Plague in Mahajanga, Madagascar  

Microsoft Academic Search

From 1995 to 1998, outbreaks of bubonic plague occurred annually in the coastal city of Mahajanga, Madagascar. A total of 1,702 clinically suspected cases of bubonic plague were reported, including 515 laboratory confirmed by Yersinia pestis isolation (297), enzyme-linked immunosorbent assay, or both. Incidence was higher in males and young persons. Most buboes were inguinal, but children had a higher

Pascal Boisier; Lila Rahalison; Monique Rasolomaharo; Maherisoa Ratsitorahina; Mahafaly Mahafaly; Maminiriana Razafimahefa; Jean-Marc Duplantier; Lala Ratsifasoamanana; Suzanne Chanteau

2002-01-01

207

A new species of shrew tenrec (Microgale jobihely) from northern Madagascar  

E-print Network

A new species of shrew tenrec (Microgale jobihely) from northern Madagascar S. M. Goodman1,2 , C. J February 2006 doi:10.1111/j.1469-7998.2006.00146.x Abstract A new species of shrew tenrec in the genus remarkable adaptive radiations found in living mammals, includes the genus Microgale or shrew tenrecs

Olson, Link

208

A new species of shrew tenrec (Microgale jobihely) from northern Madagascar  

Microsoft Academic Search

A new species of shrew tenrec in the genus Microgale is described from a series of 12 specimens taken on the south-western slopes of the Tsaratanana Massif in northern Madagascar and is named Microgale jobihely. This new species is distinguished from other named members of this endemic genus by a variety of mensural and discrete morphological characters. Phylogenetic analysis of

S. M. Goodman; C. J. Raxworthy; C. P. Maminirina; L. E. Olson

209

Understanding Mortality and the Life of the Ancestors in Rural Madagascar  

Microsoft Academic Search

Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The death in question was presented in

Rita Astuti; Paul L. Harris

2008-01-01

210

Understanding Mortality and the Life of the Ancestors in Rural Madagascar  

ERIC Educational Resources Information Center

Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The

Astuti, Rita; Harris, Paul L.

2008-01-01

211

SST Observations of the Agulhas and East Madagascar Retroflections by the TRMM Microwave Imager  

E-print Network

SST Observations of the Agulhas and East Madagascar Retroflections by the TRMM Microwave Imager Ocean to the Atlantic. The TRMM Microwave Imager (TMI) provides frequent observations of sea surface at a time. Southward propagation of features is noted along two ridges: although eddies have been found

Quartly, Graham

212

Observations of the southern East Madagascar Current and undercurrent and countercurrent system  

Microsoft Academic Search

In April 2001 four hydrographic sections perpendicular to the southern East Madagascar Current were surveyed as part of the Agulhas Current Sources Experiment. Observations with a vessel mounted and a lowered ADCP produced information on the current field while temperature, salinity, oxygen and nutrient data obtained with a CTD-Rosette system, gave information on the water mass structure of the currents

J. J. Nauw; H. M. van Aken; A. Webb; J. R. E. Lutjeharms; W. P. M. de Ruijter

2008-01-01

213

Observations of the southern East Madagascar Current and undercurrent and countercurrent system  

Microsoft Academic Search

(1) In April 2001 four hydrographic sections perpendicular to the southern East Madagascar Current were surveyed as part of the Agulhas Current Sources Experiment. Observations with a vessel mounted and a lowered ADCP produced information on the current field while temperature, salinity, oxygen and nutrient data obtained with a CTD- Rosette system, gave information on the water mass structure of

J. J. Nauw; H. M. van Aken; A. Webb; J. R. E. Lutjeharms; W. P. M. de Ruijter

2008-01-01

214

Madagascar corals reveal a multidecadal signature of rainfall and river runoff since 1708  

NASA Astrophysics Data System (ADS)

Pacific Ocean sea surface temperatures (SST) influence rainfall variability on multidecadal and interdecadal timescales in concert with the Pacific Decadal Oscillation (PDO) and Interdecadal Pacific Oscillation (IPO). Rainfall variations in locations such as Australia and North America are therefore linked to phase changes in the PDO. Furthermore, studies have suggested teleconnections exist between the western Indian Ocean and Pacific Decadal Variability (PDV), similar to those observed on interannual timescales related to the El Nio Southern Oscillation (ENSO). However, as instrumental records of rainfall are too short and sparse to confidently assess multidecadal climatic teleconnections, here we present four coral climate archives from Madagascar spanning up to the past 300 yr (1708-2008) to assess such decadal variability. Using spectral luminescence scanning to reconstruct past changes in river runoff, we identify significant multidecadal and interdecadal frequencies in the coral records, which before 1900 are coherent with Asian-based PDO reconstructions. This multidecadal relationship with the Asian-based PDO reconstructions points to an unidentified teleconnection mechanism that affects Madagascar rainfall/runoff, most likely triggered by multidecadal changes in North Pacific SST, influencing the Asian Monsoon circulation. In the 20th century we decouple human deforestation effects from rainfall-induced soil erosion by pairing luminescence with coral geochemistry. Positive PDO phases are associated with increased Indian Ocean temperatures and runoff/rainfall in eastern Madagascar, while precipitation in southern Africa and eastern Australia declines. Consequently, the negative PDO phase that started in 1998 may contribute to reduced rainfall over eastern Madagascar and increased precipitation in southern Africa and eastern Australia. We conclude that multidecadal rainfall variability in Madagascar and the western Indian Ocean needs to be taken into account when considering water resource management under a future warming climate.

Grove, C. A.; Zinke, J.; Peeters, F.; Park, W.; Scheufen, T.; Kasper, S.; Randriamanantsoa, B.; McCulloch, M. T.; Brummer, G.-J. A.

2013-03-01

215

Stone tools and foraging in northern Madagascar challenge Holocene extinction models.  

PubMed

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar's known occupational history, and thus the time during which people exploited Madagascar's environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohmar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. (14)C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton'i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050-1350, by (14)C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. (14)C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. PMID:23858456

Dewar, Robert E; Radimilahy, Chantal; Wright, Henry T; Jacobs, Zenobia; Kelly, Gwendolyn O; Berna, Francesco

2013-07-30

216

Agro-Environmental Determinants of Avian Influenza Circulation: A Multisite Study in Thailand, Vietnam and Madagascar  

PubMed Central

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 20042005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

Paul, Mathilde C.; Gilbert, Marius; Desvaux, Stphanie; Rasamoelina Andriamanivo, Harena; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Vronique

2014-01-01

217

Short message service sentinel surveillance of influenza-like illness in Madagascar, 20082012  

PubMed Central

Abstract Problem The revision of the International Health Regulations (IHR) and the threat of influenza pandemics and other disease outbreaks with a major impact on developing countries have prompted bolstered surveillance capacity, particularly in low-resource settings. Approach Surveillance tools with well-timed, validated data are necessary to strengthen disease surveillance. In 2007 Madagascar implemented a sentinel surveillance system for influenza-like illness (ILI) based on data collected from sentinel general practitioners. Setting Before 2007, Madagascars disease surveillance was based on the passive collection and reporting of data aggregated weekly or monthly. The system did not allow for the early identification of outbreaks or unexpected increases in disease incidence. Relevant changes An innovative case reporting system based on the use of cell phones was launched in March 2007. Encrypted short message service, which costs less than 2 United States dollars per month per health centre, is now being used by sentinel general practitioners for the daily reporting of cases of fever and ILI seen in their practices. To validate the daily data, practitioners also report epidemiological and clinical data (e.g. new febrile patients sex, age, visit date, symptoms) weekly to the epidemiologists on the research team using special patient forms. Lessons learnt Madagascars sentinel ILI surveillance system represents the countrys first nationwide real-time surveillance system. It has proved the feasibility of improving disease surveillance capacity through innovative systems despite resource constraints. This type of syndromic surveillance can detect unexpected increases in the incidence of ILI and other syndromic illnesses. PMID:22589573

Rajatonirina, Soatiana; Heraud, Jean-Michel; Randrianasolo, Laurence; Orelle, Arnaud; Razanajatovo, Norosoa Harline; Raoelina, Yolande Nirina; Ravolomanana, Lisette; Rakotomanana, Fanjasoa; Ramanjato, Robinson; Randrianarivo-Solofoniaina, Armand Eugne

2012-01-01

218

Geological evolution of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The Antongil Craton, along with the Masora and Antananarivo cratons, make up the fundamental Archaean building blocks of the island of Madagascar. They were juxtaposed during the late-Neoproterozoic to early Palaeozoic assembly of Gondwana. In this paper we give a synthesis of the geology of the Antongil Craton and present previously published and new geochemical and U-Pb zircon analyses to provide an event history for its evolution.The oldest rocks in the Antongil Craton form a nucleus of tonalitic gneiss, characteristic of Palaeo-Mesoarchaean cratons globally, including phases dated between 3320 ?? 14. Ma to 3231 ?? 6. Ma and 3187 ?? 2. Ma to 3154 ?? 5. Ma. A series of mafic dykes was intruded into the Mesoarchaean tonalites and a sedimentary succession was deposited on the craton prior to pervasive deformation and migmatisation of the region. The age of deposition of the metasediments has been constrained from a volcanic horizon to around 3178 ?? 2. Ma and subject to migmatisation at around 2597 ?? 49. Ma. A subsequent magmatic episode generated voluminous, weakly foliated granitic rocks, that also included additions from both reworked older crustal material and younger source components. An earlier granodiorite-dominated assemblage, dated between 2570 ?? 18. Ma and 2542 ?? 5. Ma, is largely exposed in xenoliths and more continuously in the northern part of the craton, while a later monzogranite-dominated phase, dated between 2531 ?? 13. Ma and 2513 ?? 0.4. Ma is more widely developed. Together these record the stabilisation of the craton, attested to by the intrusion of a younger dyke swarm, the age of which is constrained by a sample of metagabbro dated at 2147 ?? 6. Ma, providing the first evidence for Palaeoproterozoic rocks from the Antongil Craton.The youngest events recorded in the isotopic record of the Antongil Craton are reflected in metamorphism, neocrystallisation and Pb-loss at 792 ?? 130. Ma to 763 ?? 13. Ma and 553 ?? 68. Ma. These events are interpreted as being the only manifestation of the Pan-African orogeny seen in the craton, which led to the assembly of the tectonic blocks that comprise the island. ?? 2010 NERC.

Schofield, D.I.; Thomas, R.J.; Goodenough, K.M.; De Waele, B.; Pitfield, P.E.J.; Key, R.M.; Bauer, W.; Walsh, G.J.; Lidke, D.J.; Ralison, A.V.; Rabarimanana, M.; Rafahatelo, J.-M.; Randriamananjara, T.

2010-01-01

219

Two new eimerians (Apicomplexa) from insectivorous mammals in Madagascar.  

PubMed

Fecal samples from 126 insectivorous mammals in Madagascar were collected between spring 1999 and fall 2001. In the Afrosoricida, 21 species in 5 genera were sampled, including 17 species of Microgale (31/96, 32% infected), Hemicentetes semispinosus (1/2, 50%), Oryzorictes hova (1/5, 20%), Setifer setosus (8/13, 61.5%), and Tenrec ecaudatus (5/8, 62.5%); in the Soricomorpha, only Suncus murinus was examined and 1/2 (50%) were infected. Two morphotypes of eimeriid oocysts, representing 2 presumptive new species, were found in 47 (37%) infected animals; only 2 afrosoricid hosts (2% of all hosts, 4% of infected hosts) had both oocyst morphotypes. Sporulated oocysts of the first morphotype, Eimeria tenrececaudata n. sp., are subspheroidal, 18.8 17.4 (17-22 15-20), with a length?width ratio (L/W) of 1.1 (1.0-1.2); they lack a micropyle but may contain 0-2 polar granules and a single, small round oocyst residuum, 3 2.3. Sporocysts are lemon-shaped, 9.9 6.6 (9-11 5-8), with a L/W of 1.5 (1.2-2.0); they have a prominent, slightly flattened Stieda body and a substieda body but lack a parastieda body. The sporocyst residuum consists of only a few granules between the sporozoites, which are sausage-shaped and have a large posterior refractile body. Oocysts of the second morphotype, Eimeria setifersetosa n. sp. are spheroidal to subspheroidal, 30.1 28.6 (27-34 25-34), with a L/W of 1.1 (1.0-1.2); they lack both micropyle and oocyst residuum, but 1-2 polar granules are usually present. Sporocysts are subspheroidal to broadly ellipsoidal, 9.6 7.3 (9-11 6-8), with a L/W of 1.3 (1.1-1.7); they have a broad Stieda body, lack sub- and parastieda bodies, and have a residuum of a few granules scattered throughout the sporocyst. Sporozoites were not clearly defined, but what seemed to be a single large refractile body is seen, presumably in each sporozoite. PMID:21506791

Couch, Lee; Laakkonen, Juha; Goodman, Steven; Duszynski, Donald W

2011-04-01

220

Griveaudus gen. nov. (Hemiptera: Fulgoromorpha: Flatidae) from Tsaratanana Massif supports the biodiversity of montane flatids in Madagascar.  

PubMed

The paper describes a new flatid genus, Griveaudus gen. nov., comprising two species G. issidiformis sp. nov. and G. tsarantananae sp. nov. from Madagascar. Additionally, the illustrations of the female internal genital structures are provided. PMID:25283392

Stroi?ski, Adam; Swierczewski, Dariusz

2014-01-01

221

A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar  

E-print Network

, and in some cases challenging, aspects of this general model. Results Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central...

Ricaut, Francois-X; Razafindrazaka, Harilanto; Cox, Murray P; Dugoujon, Jean-M; Guitard, Evelyne; Sambo, Clement; Mormina, Maru; Mirazon-Lahr, Marta; Ludes, Bertrand; Crubezy, Eric

2009-12-14

222

Filling the Gondwana gaps: new species and new reports of Beatogordius Heinze, 1934 (Nematomorpha) from Australia and Madagascar  

Microsoft Academic Search

We describe two new species of Beatogordius Heinze, 1934 (Nematomorpha), B.australiensis and B.lineatus, from Queensland, Australia. One further species, B.abbreviatus (Villot, 1874), which was known from Reunion, is reported from Madagascar. These new reports extend the range of Beatogordius from Africa and South America to include Madagascar and Australia. Beatogordius was likely distributed over the Gondwana continent prior to the

Andreas Schmidt-Rhaesa; Malcom S. Bryant

2004-01-01

223

Comparison of carabid beetle (Coleoptera: Carabidae) occurrence in rain forest and human-modified sites in south-eastern Madagascar  

Microsoft Academic Search

High species diversity and endemism make Madagascar one of the world's biodiversity hot spots. However, forest cover and,\\u000a thereby, biodiversity are decreasing rapidly due to human activities. Most of Madagascar is now covered by secondary vegetation,\\u000a which is species-poor and contains many introduced species. In this study, the effect of human impact through alteration in\\u000a vegetation on carabid beetles (Coleoptera:

Johanna Rainio; Jari Niemel

2006-01-01

224

Les transferts de gestion des ressources naturelles : quelles consquences sur les systmes socio-cologiques de fort sche Madagascar et au Niger ?  

E-print Network

-écologiques de forêt sèche à Madagascar et au Niger ? Auteurs : Rives Fanny, Aubert Sigrid et Montagne Pierre Résumé Dans les zones de forêts sèches à Madagascar et au Niger, les systèmes socio-écologiques sont pour comprendre comment les politiques forestières ont évolué à Madagascar et au Niger pour atteindre

Boyer, Edmond

225

Le prix n'est pas la seule valeur d'existence chez les Uraniidae de Madagascar par Claude Marcel HLADIK  

E-print Network

Le prix n'est pas la seule valeur d'existence chez les Uraniidae de Madagascar par Claude Marcel de la côte ouest de Madagascar, j'ai découvert avec surprise les restes d'un lépidoptère à demi, lors de précédents voyages à Madagascar. Cependant je pensais que cette espèce venait exclusivement des

226

Epidemiologic features of four successive annual outbreaks of bubonic plague in Mahajanga, Madagascar.  

PubMed

From 1995 to 1998, outbreaks of bubonic plague occurred annually in the coastal city of Mahajanga, Madagascar. A total of 1,702 clinically suspected cases of bubonic plague were reported, including 515 laboratory confirmed by Yersinia pestis isolation (297), enzyme-linked immunosorbent assay, or both. Incidence was higher in males and young persons. Most buboes were inguinal, but children had a higher frequency of cervical or axillary buboes. Among laboratory-confirmed hospitalized patients, the case-fatality rate was 7.9%, although all Y. pestis isolates were sensitive to streptomycin, the recommended antibiotic. In this tropical city, plague outbreaks occur during the dry and cool season. Most cases are concentrated in the same crowded and unsanitary districts, a result of close contact among humans, rats, and shrews. Plague remains an important public health problem in Madagascar, and the potential is substantial for spread to other coastal cities and abroad. PMID:11927030

Boisier, Pascal; Rahalison, Lila; Rasolomaharo, Monique; Ratsitorahina, Maherisoa; Mahafaly, Mahafaly; Razafimahefa, Maminirana; Duplantier, Jean-Marc; Ratsifasoamanana, Lala; Chanteau, Suzanne

2002-03-01

227

Isotope characterization of shallow aquifers in the Horombe region, South of Madagascar  

E-print Network

The present study deals with the problem of evaluation of the recharge mechanism and the characterization of the groundwater flow system in the basement shallow aquifer, which is one of the groundwater resource in the semi-arid South region of Madagascar. Stable isotopes (deuterium and oxygen-18) and tritium are used to achieve with accuracy the hydrogeological and geochemical dynamics study. Chemical analysis is used to provide complementary information to the investigation. A space distribution of tritium concentration and isotopic composition in groundwater shows evidence of two opposite categories of aquifers, which is confirmed by the chemical analysis results and by the geological features of the study site. Some groundwater flow path directions have been identified in the study area thanks to the tritium concentration space distribution and the geological formation. Besides, the groundwater recharge of the shallow aquifers in the South of Madagascar has been characterized by the exponential mixing mode...

Fareze, L P; Ramaroson, V; Andriambololona, Raoelina; Andriamiarintsoa, G; Razafitsalama, P R; Rahobisoa, J J; Randrianarison, H; Ranaivoarisoa, A; Marah, H

2012-01-01

228

Deforestation history of the eastern rain forests of Madagascar from satellite images  

SciTech Connect

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain forest remained, representing only 50% of the 7.6 million hectares existing in 1950 and 34% of the estimated original extent (11.2 million hectares). Between 1950 and 1985, the rate of deforestation averaged 111,000 hectares per year. Deforestation was most rapid in areas with low topographic relief and high population density. If cutting of forests continues at the same pace, only forests on the steepest slopes will survive the next 35 years.

Green, G.M.; Sussman, R.W. (Washington Univ., St. Louis, MO (USA))

1990-04-13

229

Troop Continuity and Troop Spacing in Propithecus verreauxi and Lemur catta at Berenty (Madagascar)  

Microsoft Academic Search

Sifaka troops (Propithecus verreauxi) at Berenty, Madagascar, seem stable numerically, geographically, and in pacing behavior. Recognizeable individuals preserved their 19631964 ranges in 1970, in a classical mosaic of defended territories. Lemur catta had twice as many troops of half the mean size in 1970, and had changed from spatial exclusivity to time-plan spacing, both within and between troops, with inter-troop

Alison Jolly

1972-01-01

230

The impact of selective logging on forest structure and tenrec populations in western Madagascar  

Microsoft Academic Search

Cette tude met en vidence quelques effets de l'exploitation slctive de la fort sur la structure de la vgtation et les consquences pour deux espces de tenrecs dans une fort sche l'ouest de Madagascar. Dans un domaine limit, l'exploitation de bois de moins de 10 m3 par ha change considrablement la structure de la fort. Mais si on considre

J. U. Ganzhorn; A. W. Ganzhorn; J.-P. Abraham; L. Andriamanarivo; A. Ramananjatovo

1990-01-01

231

Liberalization and Food Price Distributions: ARCH-M Evidence From Madagascar  

Microsoft Academic Search

There is no well-articulated theory of how stochastic food prices respond to economic liberalization measures, a surprising oversight in the vast literature on market-oriented reforms. This paper presents reduced form estimates of the effects of liberalization measures on food commodity prices in Madagascar using autoregressive conditional heteroskedastic in mean (ARCH-M) methods. The data indicate that the short-term effects of liberalization

Christopher B. Barrett

1997-01-01

232

A Molecular Phylogeny of Four Endangered Madagascar Tortoises Based on MtDNA Sequences  

Microsoft Academic Search

Four of the five tortoise species in Madagascar,Pyxis arachnoides, P. planicauda, Geochelone radiata,andG. yniphora,are endemic and on the verge of extinction. Their phylogenetic relationships remain controversial and unresolved. Here we address the phylogeny of this group using DNA sequences for the 12S and 16S rDNA and cytbgenes in mitochondrial DNA. As outgroups we used two species ofGeochelone, pardalis(mainland Africa) andnigra(Galpagos),

Adalgisa Caccone; George Amato; Oliver C. Gratry; John Behler; Jeffrey R. Powell

1999-01-01

233

Cycles of Activity, Group Composition, and Diet of Lemur mongoz mongoz Linnaeus 1766 in Madagascar  

Microsoft Academic Search

A preliminary study of the ecology and behavior of Lemur mongoz mongoz was carried out in the northwest of Madagascar. The animals were observed for approximately 250 h in July till August, 1973, and for 50 h in June, 1974. L.m.mongoz has been reported to be diurnal and to live in groups of 68 individuals. However, we found the animals

Robert W. Sussman; Ian Tattersall

1976-01-01

234

Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascar  

USGS Publications Warehouse

The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern domain, the period of early crust formation is extended to the Paleo-Mesoarchean (3.32-3.15 Ga) and a supracrustal sequence (Fenerivo Group), deposited at 3.18 Ga and metamorphosed at 2.55 Ga, is identified. In the central domain, a Neoarchean period of high-grade metamorphism and anatexis that affected both felsic (Betsiboka Suite) and mafic gneisses (Tsaratanana Complex) is documented. We propose, therefore, that the Antananarivo domain was amalgamated within the Greater Dharwar Craton (India + Madagascar) by a Neoarchean accretion event (2.55-2.48 Ga), involving emplacement of juvenile igneous rocks, high-grade metamorphism, and the juxtaposition of disparate belts of mafic gneiss and schist (metagreenstones). The concept of the "Betsimisaraka suture" is dispelled and the zone is redefined as a domain of Neoproterozoic metasedimentary (Manampotsy Group) and metaigneous rocks (Itsindro-Imorona Suite) formed during a period of continental extension and intrusive igneous activity between 840 and 760 Ma. Younger orogenic convergence (560-520 Ma) resulted in east-directed overthrusting throughout south Madagascar and steepening with local inversion of the domain in central Madagascar. Along part of its length, the Manampotsy Group covers the boundary between the eastern and central Archean domains and is overprinted by the Angavo-Ifanadiana high-strain zone that served as a zone of crustal weakness throughout Cretaceous to Recent times.

Tucker, R.D.; Roig, J.-Y.; Delor, C.; Amlin, Y.; Goncalves, P.; Rabarimanana, M.H.; Ralison, A.V.; Belcher, R.W.

2011-01-01

235

A new genus and species of freshwater crab from Madagascar (Decapoda, Brachyura, Potamoidea, Potamonautidae).  

PubMed

A new genus and species of freshwater crab is described from Madagascar. The new species is morphologically closest to the three species of the genus Foza Reed & Cumberlidge, 2006, but can easily be distinguished by having a completely smooth carapace with an unarmed anterolateral margin and a mandible with a distinctly shortened anterior lobe. This unusual suite of characters is sufficient to warrant the recognition of a new monotypic genus to accommodate this species. PMID:25543766

Meyer, Kirstin S; Cumberlidge, Neil; Koppin, Jennifer C

2014-01-01

236

The boundary currents east and north of Madagascar 2. Direct measurements and model comparisons  

Microsoft Academic Search

Moored current measurements of 11-month duration were carried out in the boundary currents east of Madagascar, near 12S at Cape Amber where the mean current flows northwestward and near 23S where the mean current flows approximately southward. Transports derived from the moored current measurements in the depth range 150-1100 m compare resonably well with those derived from ship sections by

Friedrich Schott; Michle Fieux; John Kindle; John Swallow; Rainer Zantopp

1988-01-01

237

The Effects of Habitat Disturbance on Lemurs at Ranomafana National Park, Madagascar  

Microsoft Academic Search

The alarming rate of deforestation in Madagascar is driving some endemic primates to extinction. Surprisingly, anthropogenic\\u000a habitat disturbance is not always deleterious. The effect of disturbance on lemur abundance may be related to diet, with frugivorous\\u000a species more prone to population declines than folivores or insectivores. To test the effects of disturbance on lemur abundance\\u000a and group size, we surveyed

James P. Herrera; Patricia C. Wright; Elise Lauterbur; Lantonirina Ratovonjanahary; Linda L. Taylor

238

Degrading uplands in the rainforest region of Madagascar: Fallow biomass, nutrient stocks, and soil nutrient availability  

Microsoft Academic Search

Soil fertility restoration depends on natural fallows in the slash-and-burn system of eastern Madagascar. In the Beforona-Vohidrazana\\u000a study zone, none of the fallow species are able to withstand the slashing, burning and cropping frequencies of 35years.\\u000a Eventually soils are abandoned for agriculture. Along the degradation sequence, this study quantifies fallow biomass, nutrient\\u000a stocks and soil nutrient availability of four dominant

Erika Styger; Erick C. M. Fernandes; Harivelo M. Rakotondramasy; Eric Rajaobelinirina

2009-01-01

239

Madagascar as a Model Region for the Study of Tempo and Pattern in Adaptive Radiations  

Microsoft Academic Search

The comparative study of adaptive radiations is a fruitful field that allows to test hypotheses and predictions of evolutionary\\u000a theory. Madagascar is ideal for such studies because a large number of such radiations evolved on this island in isolation.\\u000a In vertebrates, the historical biogeography of many Malagasy groups has recently been elucidated by molecular phylogenetic\\u000a analyses, and by molecular time

Miguel Vences

2005-01-01

240

Chromosomal evolution in tenrecs ( Microgale and Oryzorictes , Tenrecidae) from the Central Highlands of Madagascar  

Microsoft Academic Search

Tenrecs (Tenrecidae) are a widely diversified assemblage of small eutherian mammals that occur in Madagascar and Western and\\u000a Central Africa. With the exception of a few early karyotypic descriptions based on conventional staining, nothing is known\\u000a about the chromosomal evolution of this family. We present a detailed analysis of G-banded and molecularly defined chromosomes\\u000a based on fluorescence in situ hybridization

C. Gilbert; S. M. Goodman; V. Soarimalala; L. E. Olson; P. C. M. OBrien; F. F. B. Elder; F. Yang; M. A. Ferguson-Smith; T. J. Robinson

2007-01-01

241

The Hippoboscidae (Insecta: Diptera) from Madagascar, with new records from the Parc National de Midongy Befotaka  

PubMed Central

The Hippoboscidae or louse-flies is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the Parc National de Midongy Befotaka, southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticornis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented. PMID:21678788

Rahola, N.; Goodman, S.M.; Robert, V.

2011-01-01

242

Crystallographic Study of U-Th bearing minerals in Tranomaro, Anosy Region- Madagascar  

E-print Network

As an alternative to conventional fossil fuel, there is a renewed interest in the nuclear fuel to support increasing energy demand. New studies are then undertaken to characterize Madagascar U-Th bearing minerals. This is the case for the urano-thorianite bearing pyroxenites in the south East of Madagascar. In this region, several quarries were abandoned, after being mined by the French Atomic Energy Commission (C.E.A) in the fifties and sixties and are now explored by new mining companies. For this purpose, seven U-Th bearing mineral samples from old abandoned uranium quarries in Tranomaro, Amboasary Sud, Madagascar (46{\\deg} 28' 0"E, 24{\\deg} 36' 0"S), have been collected. To determine the mineral microstructure, they were investigated for qualitative and quantitative identification of crystalline compounds using X-ray powder diffraction analytical method (XRD). Results showed that the U and Th compounds, as minor elements, are present in various crystalline structures. This is important to understand their...

Sahoa, F E; Andriambololona, Raoelina; Geckeis, H; Marquardt, C; Finck, N

2012-01-01

243

Diversification of an emerging pathogen in a biodiversity hotspot: Leptospira in endemic small mammals of Madagascar.  

PubMed

Biodiversity hotspots and associated endemism are ideal systems for the study of parasite diversity within host communities. Here, we investigated the ecological and evolutionary forces acting on the diversification of an emerging bacterial pathogen, Leptospira spp., in communities of endemic Malagasy small mammals. We determined the infection rate with pathogenic Leptospira in 20 species of sympatric rodents (subfamily Nesomyinae) and tenrecids (family Tenrecidae) at two eastern humid forest localities. A multilocus genotyping analysis allowed the characterization of bacterial diversity within small mammals and gave insights into their genetic relationships with Leptospira infecting endemic Malagasy bats (family Miniopteridae and Vespertilionidae). We report for the first time the presence of pathogenic Leptospira in Malagasy endemic small mammals, with an overall prevalence of 13%. In addition, these hosts harbour species of Leptospira (L. kirschneri, L. borgpetersenii and L. borgpetersenii group B) which are different from those reported in introduced rats (L. interrogans) on Madagascar. The diversification of Leptospira on Madagascar can be traced millions of years into evolutionary history, resulting in the divergence of endemic lineages and strong host specificity. These observations are discussed in relation to the relative roles of endemic vs. introduced mammal species in the evolution and epidemiology of Leptospira on Madagascar, specifically how biodiversity and biogeographical processes can shape community ecology of an emerging pathogen and lead to its diversification within native animal communities. PMID:24784171

Dietrich, Muriel; Wilkinson, David A; Soarimalala, Voahangy; Goodman, Steven M; Dellagi, Koussay; Tortosa, Pablo

2014-06-01

244

Plants traditionally prescribed to treat tazo (malaria) in the eastern region of Madagascar  

PubMed Central

Background Malaria is known as tazo or tazomoka in local terminology in Madagascar. Within the context of traditional practice, malaria (and/or malaria symptoms) is commonly treated by decoctions or infusions from bitter plants. One possible approach to the identification of new antimalarial drug candidates is to search for compounds that cure or prevent malaria in plants empirically used to treat malaria. Thus, it is worth documenting the ethnobotanical data, and testing the antiplasmodial activity of the extractive from plants. Methods We interviewed traditional healers, known locally as ombiasy, at Andasibe in the eastern, rainy part of Madagascar. We recorded details of the preparation and use of plants for medicinal purposes. We extracted five alkaloids from Z. tsihanimposa stem bark, and tested them in vitro against Plasmodium falciparum FCM29. Results We found that traditional healers treat malaria with herbal remedies consisting of one to eight different plants. We identified and listed the medicinal plants commonly used to treat malaria. The plants used included a large number of species from different families. Zanthoxylum sp (Rutaceae) was frequently cited, and plants from this genus are also used to treat malaria in other parts of Madagascar. From the plant list, Zanthoxylum tsihanimposa, bitter plant endemic to Madagascar, was selected and examined. Five alkaloids were isolates from the stem bark of this plant, and tested in vitro against malaria parasite. The geometric mean IC50 values ranged from 98.4 to 332.1 micromolar. The quinoline alkaloid gamma-fagarine exhibited the strongest antiplasmodial activity. Conclusions The current use of plants for medicinal purposes reflects the attachment of the Malagasy people to their culture, and also a lack of access to modern medicine. The possible extrapolation of these in vitro findings, obtained with plant extracts, to the treatment of malaria and/or the signs evoking malaria is still unclear. If plants are to be used as sources of novel antimalarial compounds, we need to increase our knowledge of their empirical use to improve plant selection. In the hope of preserving useful resources, we should now gather and record ethnobotanical data in Madagascar, and should try to bridge the gaps between empirics and realism. PMID:12921540

Randrianarivelojosia, Milijaona; Rasidimanana, Valrie T; Rabarison, Harison; Cheplogoi, Peter K; Ratsimbason, Michel; Mulholland, Dulcie A; Mauclre, Philippe

2003-01-01

245

The epidemiological transition in Antananarivo, Madagascar: an assessment based on death registers (19002012)  

PubMed Central

Background Madagascar today has one of the highest life expectancies in sub-Saharan Africa, despite being among the poorest countries in the continent. There are relatively few detailed accounts of the epidemiological transition in this country due to the lack of a comprehensive death registration system at the national level. However, in Madagascars capital city, death registration was established around the start of the 20th century and is now considered virtually complete. Objective We provide an overview of trends in all-cause and cause-specific mortality in Antananarivo to document the timing and pace of the mortality decline and the changes in the cause-of-death structure. Design Death registers covering the period 19762012 were digitized and the population at risk of dying was estimated from available censuses and surveys. Trends for the period 19001976 were partly reconstructed from published sources. Results The crude death rate stagnated around 30 until the 1940s in Antananarivo. Mortality declined rapidly after the World War II and then resurged again in the 1980s as a result of the re-emergence of malaria and the collapse of Madagascars economy. Over the past 30 years, impressive gains in life expectancy have been registered thanks to the unabated decline in child mortality, despite political instability, a lasting economic crisis and the persistence of high rates of chronic malnutrition. Progress in adult survival has been more modest because reductions in infectious diseases and diseases of the respiratory system have been partly offset by increases in cardiovascular diseases, neoplasms, and other diseases, particularly at age 50 years and over. Conclusions The transition in Antananarivo has been protracted and largely dependent on anti-microbial and anti-parasitic medicine. The capital city now faces a double burden of communicable and non-communicable diseases. The ongoing registration of deaths in the capital generates a unique database to evaluate the performance of the health system and measure intervention impacts. PMID:24848650

Masquelier, Bruno; Waltisperger, Dominique; Ralijaona, Ose; Pison, Gilles; Ravlo, Arsne

2014-01-01

246

Studying the erosion of Madagascar's unique landscape has allowed geologist Dr Rnadh Cox to offer Malagasy students unique opportunities to realise their full professional potential, as she explains here  

E-print Network

Studying the erosion of Madagascar's unique landscape has allowed geologist Dr Rónadh Cox to offer-rock projects in Madagascar, but as I travelled around I was intrigued by the spectacular gullies storm wave movement of boulders. Could you explain more about this? Far from Madagascar, the Aran

Cox, Rónadh

247

Alpert, G. D. 2007. A review of the ant genus Metapone Forel from Madagascar, pp. 8-18. In Snelling, R. R., B. L. Fisher, and P. S. Ward (eds). Advances in ant systematics (Hymenoptera  

E-print Network

Alpert, G. D. 2007. A review of the ant genus Metapone Forel from Madagascar, pp. 8-18. In Snelling. A REVIEW OF THE ANT GENUS METAPONE FOREL FROM MADAGASCAR Gary D. Alpert Entomology Department Museum northeastern Madagascar. Several nest series of M. vincimus were collected from within a log in association

Villemant, Claire

248

The re-stocking of captive-bred ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve, Madagascar: methodology and recommendations  

Microsoft Academic Search

Since November 1997 the Madagascar Fauna Group has released 13 captive-bred black and white ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve in eastern Madagascar. The release programme has three major aims: (1) to assess the ability of captive-bred V. v. variegata to adapt to life in their natural habitat; (2) to investigate the contribution that such a release

Adam Britt; Charles Welch; Andrea Katz; Bernard Iambana; Ingrid Porton; Randall Junge; Graham Crawford; Cathy Williams; David Haring

2004-01-01

249

Deep phylogenetic divergence between Scolytoplatypus and Remansus, a new genus of Scolytoplatypodini from Madagascar (Coleoptera, Curculionidae, Scolytinae).  

PubMed

Scolytoplatypodini Blandford is a monotypic tribe of ambrosia beetles found in Asia, Madagascar and Africa. Only three species are currently known from Madagascar and four additional species are here described as new to science. Phylogenetic analyses of morphological and molecular data revealed that four of the seven endemic species are deeply separated from all other species by genetic and distinct morphological characters and therefore placed in a new genus Remansus Jordal. The split between this ancient lineage and Scolytoplatypus Schaufuss was estimated to approximate Palaeocene age (63 Ma), extending the minimum age of ambrosia feeding for this tribe to the beginning of the Palaeocene?Eocene thermal maximum (PETM). In addition to the ancient origin of Remansus in Madagascar during the Palaeocene, a second origin occurred in Scolytoplatypus no more than 13 Ma. A geographical origin of the latter in South-Eastern Africa was unequivocally inferred from the phylogenies. PMID:24294090

Jordal, Bjarte H

2013-01-01

250

Deep phylogenetic divergence between Scolytoplatypus and Remansus, a new genus of Scolytoplatypodini from Madagascar (Coleoptera, Curculionidae, Scolytinae)  

PubMed Central

Abstract Scolytoplatypodini Blandford is a monotypic tribe of ambrosia beetles found in Asia, Madagascar and Africa. Only three species are currently known from Madagascar and four additional species are here described as new to science. Phylogenetic analyses of morphological and molecular data revealed that four of the seven endemic species are deeply separated from all other species by genetic and distinct morphological characters and therefore placed in a new genus Remansus Jordal. The split between this ancient lineage and Scolytoplatypus Schaufuss was estimated to approximate Palaeocene age (63 Ma), extending the minimum age of ambrosia feeding for this tribe to the beginning of the Palaeocene?Eocene thermal maximum (PETM). In addition to the ancient origin of Remansus in Madagascar during the Palaeocene, a second origin occurred in Scolytoplatypus no more than 13 Ma. A geographical origin of the latter in South-Eastern Africa was unequivocally inferred from the phylogenies. PMID:24294090

Jordal, Bjarte H.

2013-01-01

251

Diet, activity patterns, foraging movement and responses to deforestation of the aquatic tenrec Limnogale mergulus (Lipotyphla: Tenrecidae) in eastern Madagascar  

Microsoft Academic Search

Abstract The aquatic or web-footed,tenrec Limnogale,mergulus,is a semi-aquatic,lipotyphlan,insectivore known,only from,stream,habitats of eastern Madagascar.,Limnogale,is considered,a high conservation,priority because of its rarity, suspected vulnerability to habitat degradation, and unique ecological niche on the island. However, its ecology and behaviour remain poorly understood. Quantitative faecal analysis and radio- tracking,were,used,to study,the diet and,foraging,activity of Limnogale,in eastern Madagascar.,Faecal pellet counts,along forest and,zero-canopy,streams,were,also conducted,to examine,the response,of

Jonathan P. Benstead; Kevin H. Barnes; Catherine M. Pringle

2001-01-01

252

Edge effects and their influence on lemur density and distribution in Southeast Madagascar.  

PubMed

Edge effects are caused by the penetration of abiotic and biotic conditions from the matrix into forest interiors. Although edge effects influence the biogeography of many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs due to the loss of 80-90% of forests in Madagascar. In this study, data are presented on how biotic edge effects influenced the distribution and density of lemurs in the Vohibola III Classified Forest in southeastern Madagascar. In total, 415 lemur surveys were conducted during June-October 2003 and May-September 2004 along six 1,250-m transects that ran perpendicular to the forest edge. Data were also collected on lemur food trees along the six transects (density, height, diameter at breast height, area, volume, and distance to forest edge). Four nocturnal species (Avahi laniger, Cheirogaleus major, Lepilemur microdon, and Microcebus rufus) and four diurnal species (Eulemur rubriventer, Eulemur fulvus rufus, Hapalemur grisesus griseus, and Propithecus diadema edwardsi) were sighted during surveys. Regression analyses of lemur densities as a function of distance to forest edge provided edge tolerances for A. laniger (edge-tolerant), M. rufus (edge-tolerant), E. rubriventer (edge-tolerant or omnipresent), and H. g. griseus (omnipresent). The density and distribution of M. rufus and their foods trees were correlated. Edge-related variations in food quality and predation pressures may also be influencing lemurs in Vohibola III. Tolerance for edge effects may explain, in part, how lemurs have survived extreme habitat loss and forest fragmentation in southeastern Madagascar. PMID:16323178

Lehman, Shawn M; Rajaonson, Andry; Day, Sabine

2006-02-01

253

Timely estrus in wild brown mouse lemur females at Ranomafana National Park, southeastern Madagascar.  

PubMed

The small-bodied nocturnal mouse lemurs (genus Microcebus) occupy a variety of habitats in Madagascar. Gray (M. murinus) and brown (M. rufus) mouse lemurs have been widely studied both in the wild and captivity. Whereas captive studies revealed an endogenous regulation of reproduction entrained by photoperiod, field studies have suggested that reproductive activation could be affected by additional climatic, physical, or social conditions. I collected data on wild brown mouse lemur females at Ranomafana between 2004 and 2008 to determine: 1) the timing of estrus and estrous periodicities across multiple seasons, and 2) whether additional factors such as body mass, age, or rainfall are correlated with onset of reproduction. In mouse lemur females at Ranomafana, the first seasonal estrus occurs 3-4 weeks after the vernal equinox. I report ~1 month's intra-population variation in the timing of estrus and inter-annual estrous intervals with periodicities of ~365 days. There were significant differences between the onset of reproduction across years. Estrous onset was uncorrelated with body mass, but there was an apparent age effect. There was a significant negative correlation between August rainfall and onset of reproduction when 2004 data were removed from the analysis. Results from this study are consistent with the notion that timing of estrus is photoperiod-dependent. As in captivity, intra-population variation in estrous onset is ~4 weeks in length. In the wild, variation in estrous onset and polyestry (multiple reproductive opportunities per year) appear to be favored under the highly unpredictable conditions of Madagascar's environments. In the wild, variation in estrous onset and polyestry (multiple reproductive opportunities per year) appear to be favored under the highly unpredictable conditions of Madagascar's environments. PMID:21469075

Blanco, Marina B

2011-06-01

254

Evaluating ring-tailed lemurs (Lemur catta) from southwestern Madagascar for a genetic population bottleneck.  

PubMed

In light of historical and recent anthropogenic influences on Malagasy primate populations, in this study ring-tailed lemur (Lemur catta) samples from two sites in southwestern Madagascar, Beza Mahafaly Special Reserve (BMSR) and Tsimanampetsotsa National Park (TNP), were evaluated for the genetic signature of a population bottleneck. A total of 45 individuals (20 from BMSR and 25 from TNP) were genotyped at seven microsatellite loci. Three methods were used to evaluate these populations for evidence of a historical bottleneck: M-ratio, mode-shift, and heterozygosity excess tests. Three mutation models were used for heterozygosity excess tests: the stepwise mutation model (SMM), two-phase model (TPM), and infinite allele model (IAM). M-ratio estimations indicated a potential bottleneck in both populations under some conditions. Although mode-shift tests did not strongly indicate a population bottleneck in the recent historical past when samples from all individuals were included, a female-only analysis indicated a potential bottleneck in TNP. Heterozygosity excess was indicated under two of the three mutation models (IAM and TPM), with TNP showing stronger evidence of heterozygosity excess than BMSR. Taken together, these results suggest that a bottleneck may have occurred among L. catta in southwestern Madagascar in the recent past. Given knowledge of how current major stochastic climatic events and human-induced change can negatively impact extant lemur populations, it is reasonable that comparable events in the historical past could have caused a population bottleneck. This evaluation additionally functions to highlight the continuing environmental and anthropogenic challenges faced by lemurs in southwestern Madagascar. PMID:22052208

Parga, Joyce A; Sauther, Michelle L; Cuozzo, Frank P; Jacky, Ibrahim Antho Youssouf; Lawler, Richard R

2012-01-01

255

Comparison of Marine Spatial Planning Methods in Madagascar Demonstrates Value of Alternative Approaches  

PubMed Central

The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the strict protection class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during initial stages of the planning process. Choosing an appropriate approach ultimately depends on scientific and political factors including representation targets, likelihood of adoption, and persistence goals. PMID:22359534

Allnutt, Thomas F.; McClanahan, Timothy R.; Andrfout, Serge; Baker, Merrill; Lagabrielle, Erwann; McClennen, Caleb; Rakotomanjaka, Andry J. M.; Tianarisoa, Tantely F.; Watson, Reg; Kremen, Claire

2012-01-01

256

Holocene Indian Ocean Cosmic Impacts: The Megatsunami Chevron Evidence From Madagascar  

NASA Astrophysics Data System (ADS)

The 2.6 million year Quaternary period terrestrial physical record lacks definitive crater evidence for major regional catastrophic impacts by asteroids and comets other than the 10.5-km diameter Botsumtwi structure in Ghana and the 14.0-km diameter Zhamanshin structure in Kazakhstan [1] dating between about 900 and 1100 kya. Current cosmic impact rate models suggest that an average of between 3-6 globally catastrophic impacts should have occurred on the Earth during the Quaternary, along with several additional significant regional impacts in addition to Zhamanshin and Botsumtwi. These models and data indicate that the great majority of the "missing" major impact locations would likely have occurred in poorly studied oceanic settings. Only recently have Late Quaternary and Holocene period coastal paleo-megatsunami chevron deposits been defined in the Caribbean and along the western coasts of Australia, along with the suggestion that some may have been created by oceanic cosmic impacts in distinction to those caused by landslips, eruptions, and seismic events. We investigate the possibility that many or most megatsunami chevrons occurring along the southern coast of Madagascar were caused by two or more major Holocene Indian Ocean cosmic impacts. This hypothesis is based on an initial study of the worldwide archaeological and anthropological record, and the preliminary study of satellite images of the chevrons, selected Indian Ocean deep-sea cores, sea-floor bathymetry, and physical examination of the Madagascar deposits themselves. Candidate Indian Ocean impact structures are identified and correlated with the southern Madagascar megatsunami chevron deposits. [1] Masse, W.B. 2007 The Archaeology and Anthropology of Quaternary Period Cosmic Impact. In Bobrowsky, P.T. & Rickman, H. (eds.)Comets/Asteroid Impacts and Human Society. Springer, Berlin (in press).

Masse, W.; Bryant, E.; Gusiakov, V.; Abbott, D.; Rambolamana, G.; Raza, H.; Courty, M.; Breger, D.; Gerard-Little, P.; Burckle, L.

2006-12-01

257

Tectonic significance of granitoid plutons from the Andasibe paragneiss belt, east-central Madagascar  

NASA Astrophysics Data System (ADS)

The understanding of the crustal evolution of the central Madagascar is of major significance in the study of the Precambrian basement of Madagascar and the greater Gondwana supercontinent. The study area, known as Andasibe paragneiss defines a fold belt that stretches from Ambatondrazaka to Soavina area in eastern Madagascar and is intruded by extensive granitoid intrusions. The western part of Andasibe paragneiss lies within the crustal scale Angavo shear zone, and is characterized by fine to medium-grained foliated paragneiss, which also include biotite-hornblende gneiss, migmatitic quartzofeldspathic gneiss, sillimanite-bearing gneiss, garnet-bearing gneiss, graphitic gneiss intercalates with schist, quartzite, muscovite-bearing gneiss and marble. Three samples of granitoid plutons intruding the Andasibe paragneiss yielded isotope dilution-thermal ionization mass spectrometry (ID-TIMS) U-Pb zircon ages of 801.23.8Ma, 776.54.4Ma and 772.14.2Ma. These dates are interpreted to represent the crystallization ages of these rocks and are comparable to other reported U-Pb emplacement ages for granitoid plutons within and along the north-central margin of the Angavo shear zone, which are suggested to be related to ca. 820 Ma successor-arc plutonism. These granitoids pre-dates the Angavo shear zone and folds affecting the plutons foliation are believed to have formed during the East-African Orogen, which in this part of the Malagasy Precambrian basement, is considered to have associated with Neoproterozoic extensive magmatism ca. 820 Ma to 540 Ma.

Raharimahefa, T.

2013-12-01

258

Structural mapping and analysis of a Madagascar Precambrian shear zone using enhanced Landsat Thematic Mapper Data  

SciTech Connect

Recently, the west coast of Madagascar has become a frontier region for petroleum exploration. Major structures in the Precambrian shield of Madagascar may have a strong control on the development of sedimentary basins, as has been documented in the Morondava basin. The 2.5-3.0+ Ga shield of Madagascar is an amphibolite- to granulite-grade metamorphic gneiss terrain, intruded by anorthosites and 550-Ma granites and pegmatites. Landsat Thematic Mapper data provides a cost-effective method for regional-scale structural mapping of this poorly known terrain. A five-component linear mixing model has been used to enhance the lithologic information in this six-band data. Lithologic component images thus produced utilize the full geologic spectral range of the data. A preliminary structural geologic map compiled from the component images has greater detail than existing maps at 1:100,000 scale, to which it has been compared. The Ankafotra-Saririaky shear zone has been identified as a north-northeast-trending, 15- to 20-km-wide region of appressed folds, attenuated layering, and subparallel faults on the western side of the shield. Two anorthosite massifs that occur within this shear zone have the structural characteristics of boudins in a ductile matrix. The shear deformed a preexisting terrain of poly-phase folding, characterized by tight folds and complex fold interference structures displayed by basins and domes on a scale of 10 km. Enhanced remote sensing data can be used to characterize the nature and mechanism of shear deformation in such zones.

Kilmer, D.S.; Duncan, I.J. (Washington Univ., St. Louis, MO (USA))

1990-05-01

259

Analysis of Patterns of Bushmeat Consumption Reveals Extensive Exploitation of Protected Species in Eastern Madagascar  

PubMed Central

Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted species are adequately protected. PMID:22194787

Jenkins, Richard K. B.; Keane, Aidan; Rakotoarivelo, Andrinajoro R.; Rakotomboavonjy, Victor; Randrianandrianina, Felicien H.; Razafimanahaka, H. Julie; Ralaiarimalala, Sylvain R.; Jones, Julia P. G.

2011-01-01

260

Comparison of marine spatial planning methods in Madagascar demonstrates value of alternative approaches.  

PubMed

The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the "strict protection" class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during initial stages of the planning process. Choosing an appropriate approach ultimately depends on scientific and political factors including representation targets, likelihood of adoption, and persistence goals. PMID:22359534

Allnutt, Thomas F; McClanahan, Timothy R; Andrfout, Serge; Baker, Merrill; Lagabrielle, Erwann; McClennen, Caleb; Rakotomanjaka, Andry J M; Tianarisoa, Tantely F; Watson, Reg; Kremen, Claire

2012-01-01

261

Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar)  

PubMed Central

Background The country of Madagascar is renowned for its high level of biodiversity and endemism, as well as the overwhelming pressures and threats placed on the natural resources by a growing population and climate change. Traditional medicine plays an important role in the daily lives of the Malagasy for various reasons including limited access to healthcare, limited markets and traditional values. The objective of this study was to assess the modern utitilization of the Agnalazaha Forest by the local population in Mahabo-Mananivo, Madagascar, for medicinal plants used by women, and to establish a list of medicinal plants used by women sourced from Agnalazaha Forest. Methods Ethnobotanical studies were conducted over a period of five months in 2010 to determine the diversity of medicinal plants used by women in the commune of Mahabo-Mananivo. In all, 498 people were interviewed, both male and female ranging age from 15 to over 60years old. Results 152 medicinal plants used by local people were collected during the ethnobotanical studies. Among the recorded species, eight native species are widely used by women. These species are known for their therapeutic properties in treating placental apposition and complications during childbirth as well as tropical illnesses such as malaria, filariasis, and sexual diseases like gonorrhea and syphilis. Conclusions Littoral forests are rare ecosystems that are highly threatened on the island nation of Madagascar. Our investigation into the use of medicinal plants sourced from and around the Agnalazaha Forest by the women of Mahabo-Mananivo reinforces the need for this natural resource as a first line of health care for rural families. PMID:24188563

2013-01-01

262

Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat Out of Recycled Materials  

NSDL National Science Digital Library

Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their wow factor. These characteristics make them unique as classroom insects and add to their effectiveness in increasing your students scientific knowledge. This article provides directions for building a free, eco-friendly, low-maintenance MHC home out of garbage.

Wagler, Ron

2010-04-01

263

A new Gephyromantis (Phylacomantis) frog species from the pinnacle karst of Bemaraha, western Madagascar  

PubMed Central

Abstract We describe a new mantellid frog of the subfamily Mantellinae from the karstic Bemaraha Plateau, western Madagascar. The new species belongs to the genus Gephyromantis, subgenus Phylacomantis, which previously included Gephyromantis azzurrae, Gephyromantis corvus and Gephyromantis pseudoasper. Gephyromantis atsingy sp. n. has a snout-vent length of 3543 mm and is a scansorial frog living among the Tsingy de Bemaraha pinnacles and inside the caves present in the area. A morphological analysis and biomolecular comparison revealed the degree of differentiation between these four species of the Phylacomantis subgenus.The new species seems to be endemic to Tsingy de Bemaraha. PMID:21594161

Crottini, Angelica; Glaw, Frank; Casiraghi, Maurizio; Jenkins, Richard K.B.; Mercurio, Vincenzo; Randrianantoandro, Christian; Randrianirina, Jasmin E.; Andreone, Franco

2011-01-01

264

The primates of the Baly Bay area, north-western Madagascar.  

PubMed

Primate surveys were conducted in isolated primary west Malagasy decidous forest blocks around Baly Bay, north-western Madagascar. Eight species of primate were found, including Microcebus c.f. myoxinus, Hapalemur griseus occidentalis and Phaner furcifer. Two species were found only in Namoroka Strict Nature Reserve, which may mean that other forest blocks in the area have experienced primate extinctions. The record of M. c.f. myoxinus came from mangrove, the first confirmed record of a lemur from this habitat. The pelage of female Eulemur fulvus rufus was atypical. PMID:9885334

Hawkins, A F; Durbin, J C; Reid, D B

1998-01-01

265

Geology, petrology and isotope geochemistry of massif-type anorthosites from southwest Madagascar  

Microsoft Academic Search

Four massif-type anorthosite bodies 25100?km2 in area occur within high-pressure granulite facies supracrustal gneisses in southwestern Madagascar. Two of these bodies\\u000a (Ankafotia and Saririaky) appear to have been pulled apart by 40?km in a ductile shear zone, but structural features such\\u000a as sub-vertical stretching lineations indicate an origin by intense west-directed flattening and pure shear. Country rocks\\u000a (Graphite Series) include

Lewis D. Ashwal; Michael A. Hamilton; Vincent P. I. Morel; Roger A. Rambeloson

1998-01-01

266

Analyse macro-sociolinguistique d'une situation de diglossie: le cas de Madagascar (A Macro-Sociolinguistic Analysis of a Diglossic Situation: The Case of Madagascar). Publication H-6.  

ERIC Educational Resources Information Center

The languages used in Madagascar are examined from the following perspectives: the linguistic varieties and functions socially recognized at the community level; the oppositions and complementarities that have become established between languages in contact; and the speakers' attitudes toward those varieties. The report focuses on the following

Rambelo, Michel

267

Lemur responses to edge effects in the Vohibola III classified forest, Madagascar.  

PubMed

Forest edges are dynamic zones characterized by the penetration (to varying depths and intensities) of conditions from the surrounding environment (matrix) into the forest interior. Although edge effects influence many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs because of the highly fragmented forest landscapes found in Madagascar. In this study, data are presented regarding how the densities of six lemur species (Avahi laniger, Cheirogaleus major, Eulemur rubriventer, Hapalemur griseus griseus, Microcebus rufus, and Propithecus diadema edwardsi) varied between six 500-m interior transects and six 500-m edge transects in the Vohibola III Classified Forest in SE Madagascar. Diurnal (n = 433) and nocturnal (n = 128) lemur surveys were conducted during June-October 2003 and May-November 2004. A. laniger, E. rubriventer, and H. g. griseus exhibited a neutral edge response (no differences in densities between habitats). M. rufus and P. d. edwardsi had a positive edge response (higher densities in edge habitats), which may be related to edge-related variations in food abundance and quality. Positive edge responses by M. rufus and P. d. edwardsi may ultimately be detrimental due to edge-related anthropogenic factors (e.g., hunting by local people). The negative edge response exhibited by C. major (lower densities in edge habitats) may result from heightened ambient temperatures that inhibit torpor in edge habitats. PMID:16477598

Lehman, Shawn M; Rajaonson, Andry; Day, Sabine

2006-03-01

268

Impact of the high topography of Madagascar on the structure of the Findlater Jet  

NASA Astrophysics Data System (ADS)

The cross-equatorial flow over the western Indian Ocean, known as the Findlater Jet, plays an important role in the monsoonal circulation of the region. During the boreal summer, there is southerly flow across the equator that is concentrated along the East African highlands. During the boreal winter, there is a reversal in wind direction across the equator. Madagascar, the world's fourth largest island, with heights in excess of 1 km represents a significant obstacle to the flow whose impact on this jet has not been fully characterized. Here we use diagnostic tools developed to investigate atmospheric flow distortion by Greenland's high topography to study this interaction. We show that there is a bifurcation of the Findlater Jet by Madagascar during the boreal summer and localized tip jets at the island's northern and southern ends. During the boreal winter, the northern tip jet reverses direction and weakens, while the southern tip jet maintains its direction and magnitude. We show that rotational effects are important for these interactions but not dominant and result in an enhancement of the northern tip jet; while allowing for existence of the southern tip jet. As will also be shown, this flow distortion has impacts on the meteorology and oceanography of the region including the forcing of oceanic eddies in the Mozambique Channel, a modulation of the southward displacement of the Inter-Tropical Convergence Zone (ITCZ) and a splitting of the boreal summer cross-equatorial mass transport associated with the Findlater Jet into two branches.

Moore, G. W. K.

2013-05-01

269

Modified subfossil aye-aye incisors from southwestern Madagascar: species allocation and paleoecological significance.  

PubMed

Two of the three drilled aye-aye incisors collected in 1901 by Grandidier at the subfossil site of Lamboharana were recently rediscovered in uncatalogued collections of the Institut de Palontologie in Paris. These teeth are not much wider or thicker than those of the extant aye-aye (Daubentonia madagascariensis), but their arc of curvature is noticeably greater. These facts indicate that the teeth probably belong to D. robusta, a large extinct aye-aye whose dentition is otherwise unknown. No other remains referable to Daubentonia have been reported from Lamboharana, although D. robusta is known from other localities in the southwest. The presence of Daubentonia in southern Madagascar does not demonstrate that this region was markedly more humid or densely forested in the recent past. It remains to be established whether the extinction of D. robusta throughout its range in southern Madagascar, and local disappearance of D. madagascariensis everywhere but in the eastern forest biotope, is due to late Holocene climatic change, to anthropogenic effects, or both factors combined. PMID:3254846

MacPhee, R D; Raholimavo, E M

1988-01-01

270

[KAP study (knowledge-attitude-practice) on seafood poisoning on the southwest coast of Madagascar].  

PubMed

In June and July 1996, a knowledge, attitude and practice survey concerning seafood poisonings was conducted in Tular Province, 41 villages spread along 300 km of cost, with some 34,000 inhabitants, were included in the survey. 84 seafood poisonings after fish, shark and turtle meals occurred during the period 1931 to 1995; 14 of them were responsible of deaths. The family of toxic fishes are Clupeidae, Tetraodontidae, Scaridae and Siganidae. Sphyrna lewini is the shark species the most often responsible for poisonings. Three turtle species are involved in poisonings: Eretmochelys imbricata, Chelonia mydas and Dermochelys coriacea. Clinical patterns were related to marine toxins. Although the communities were aware of the risks, there was no change in seafood meal practice. Preventive measures are not very often used. Practical techniques to detect toxins, although very simple, are not systematically carried out. For a better understanding of the seafood poisoning risk in Madagascar, a retrospective survey in the villages located in coastal areas all around Madagascar was to be carried out in 1997. An eco-toxicological survey will likewise probably be organised in an Indian Ocean regional approach. PMID:10214522

Robinson, R; Champetier de Ribes, G; Ranaivoson, G; Rejely, M; Rabeson, D

1999-02-01

271

Anatomical descriptions of silicified woods from Madagascar and Indonesia by scanning electron microscopy.  

PubMed

Fine structure and tissue substitution by minerals were investigated in silicified woods from Madagascar and Indonesia by scanning electron microscopy and X-ray microanalysis. The silicified woods maintained the exterior morphology of once grown trees and showed typical inner structures of conifers. Radial planes of the silicified wood from Madagascar revealed tracheids as a major component of the axial system in the secondary xylem. Tracheids were mainly characterized by numerous bordered pits where a thickening in the middle (torus) was surrounded with the membrane (margo). The torus appeared to contrast with the fibrillar network of the margo. As a component of the axial system in the secondary phloem, sieve elements were found to have many sieve pores that were filled with seemingly crystalline materials. To correlate the colors of the silicified wood from Indonesia with elemental composition, energy-dispersive X-ray spectrometry was employed in this study. Silicon was present as a basic component of the silicified wood. Calcium and iron were detected from red-colored regions, whereas magnesium was found in blue-colored regions. These results suggest that tissues of silicified woods had been substituted by minerals over the past period, while retaining the inherent morphology of the tree species. Scanning electron microscopy and X-ray microanalysis could be applied to unravel structural details and composition of plant fossils in palaeobotany. PMID:18280171

Yoon, Chul Jong; Kim, Ki Woo

2008-10-01

272

Rural livelihoods and access to natural capital: Differences between migrants and non-migrants in Madagascar  

PubMed Central

BACKGROUND Although natural resources play a central role in rural livelihoods across the globe, little research has explored the relationship between migration and natural capital use, particularly in combination with other livelihood capitals (i.e., human, social, financial and physical). OBJECTIVE Grounded in the rural livelihood framework, this paper explores the association between the livelihood capital availability, especially natural capital, for migrants and non-migrants in rural Madagascar. METHODS Data from the 2008/2009 Demographic and Health Survey are used in combination with satellite imagery of vegetation coverage (Normalized Difference Vegetation Index, NDVI) to proxy natural resources. Hierarchical multilevel models allow for inclusion of cross-level interactions between migrant status and proximate natural resources as determinants of the status of livelihood assets. RESULTS Three key findings emerge. First, higher levels of proximate natural resources are associated with greater financial, human, and social capital for both migrants and non-migrants. Second, migrants have, on average, greater financial, physical, human, and social capital than non-migrants, and urban-to-rural migrants do exceptionally well on all capital asset categories. Third, migrants residing in areas with higher levels of natural capital tend to have significantly higher levels of human capital (education). CONCLUSION Although we cannot examine livelihood strategies per se, the results suggest variation in livelihood potential among migrants and non-migrants in rural Madagascar, with migrants tending to have greater capital assets. In addition, access to natural resources is a central livelihood strategy. PMID:25364297

Nawrotzki, Raphael J.; Hunter, Lori M.; Dickinson, Thomas W.

2013-01-01

273

Isolation of 22 new Haliaeetus microsatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three other Haliaeetus eagle species  

USGS Publications Warehouse

We isolated a total of 22 microsatellite loci from two Haliaeetus species: the Madagascar fish-eagle (Haliaeetus vociferoides) and the bald eagle (Haliaeetus leucocephalus). Five loci were monomorphic in both the Madagascar fish-eagle (n = 24-43) and the bald eagle (n = 2-8) but were found to be polymorphic in other Haliaeetus species. Haliaeetus loci have proved useful for investigating gene flow in Haliaeetus and Aquila eagles. Ten loci were polymorphic in the critically endangered Madagascar fish-eagle and will be used to investigate the genetic population structure and mating system in this species. ?? 2007 The Authors.

Tingay, R.E.; Dawson, D.A.; Pandhal, J.; Clarke, M.L.; David, V.A.; Hailer, F.; Culver, M.

2007-01-01

274

Setting Up a Bibliographic Database from National Inventory of Scientific and Technical Literature. The CIDST Experience in Madagascar.  

ERIC Educational Resources Information Center

Describes the development of a bibliographic database in Madagascar through a national inventory of scientific and technical literature. The roles of the Ministry of Scientific and Technological Research for Development (MRSTD) and its information service, CIDST, are described; database products are discussed; and future prospects are suggested.

Andriamparany, Louis Marius; And Others

1991-01-01

275

A new species of the genus Mygdonia (Hemiptera: Heteroptera: Coreidae)
from Madagascar with a key to species.
 

PubMed

A new species, Mygdonia milivoji sp. nov. (Coreidae: Coreinae: Mictini) from south-west Madagascar is described, illustrated and compared with widely distributed M. elongata Distant, 1879. A key to Mygdonia species based on females is given and distribution of both Madagascan species is briefly discussed. PMID:25544533

Ba?a?, Petr; Brailovsky, Harry; Hub?kov, Lenka; Hemala, Vladimr

2014-01-01

276

A new species of Tophoderes Dejean from northern Madagascar with a checklist of the species (Coleoptera: Anthribidae).  

PubMed

A new species, Tophoderes lidmilae Trzna & Ba?a? sp. nov., from north Madagascar is described. Male genitalia are studied and illustrated and colour photographs of both sexes are added. A comparison with the most similar known species T. frenatus (Klug, 1833) is provided. A checklist of species of the Madagascan genus Tophoderes (Anthribidae: Anthribinae: Tophoderini) is provided. PMID:25661210

Trzna, Milo; Ba?a?, Petr

2015-01-01

277

Molecular Phylogeny and Biogeography of the Native Rodents of Madagascar (Muridae: Nesomyinae): A Test of the Single-Origin Hypothesis  

Microsoft Academic Search

Complete nucleotide sequences from the mitochondrial cytochrome b gene (1143 bp) were used to investigate the phylogenetic relationships among the native rodents of Madagascar. Specifically, this study examines whether the nine genera of nesomyines form a monophyletic group relative to other Old World murids. All nine of the nesomyine genera, including multiple individuals from 15 of the 21 described species,

Sharon A. Jansa; Steven M. Goodman; Priscilla K. Tucker

1999-01-01

278

A method for quantifying biodiversity loss and its application to a 50-year record of deforestation across Madagascar  

E-print Network

of deforestation across Madagascar Thomas F. Allnutt1,2 , Simon Ferrier3,4 , Glenn Manion3 , George V. N. Powell1 Avenue, Pittsburgh, PA, 15213, USA Keywords Biodiversity loss; deforestation; endemism; extinction of deforestation and endemism. Deforestation has been extensive, but impacts of forest loss on biodiversity have

Vermont, University of

279

A null model for species richness gradients: bounded range overlap of butterflies and other rainforest endemics in Madagascar  

Microsoft Academic Search

Species richness has classically been thought to increase from the poles towards the Equator, and from high elevations down to sea-level. However, the largest radiation of butterflies in Madagascar, the subtribe Mycalesina (c. 67 spp.) does not exhibit such a monotonic pattern, either for empirical records or for interpolated species ranges. Instead, summation of mycalesine ranges generates a domed curve

DAVID C LEES; CLAIRE KREMEN; LANTO ANDRIAMAMPIANINA

1999-01-01

280

Well-Being Is a Process of Becoming: Respondent-Led Research with Organic Farmers in Madagascar  

ERIC Educational Resources Information Center

Malagasy "players"--farmers, middle men, organic organisations and policy makers--see in export-orientated organic agriculture a way for Madagascar to build upon its historic export strengths: spices, essential oils, medicinal plants and tropical fruits. They point to the "de facto" organic status of most farming in the country and view organic

Farnworth, Cathy Rozel

2009-01-01

281

Molecular Evidence for the Monophyly of Tenrecidae (Mammalia) and the Timing of the Colonization of Madagascar by Malagasy Tenrecs  

Microsoft Academic Search

Tenrecs are a diverse family of insectivores, with an Afro-Malagasian biogeographic distribution. Three subfamilies (Geogalinae, Oryzorictinae, Tenrecinae) are restricted to Madagascar and one subfamily, the otter shrews (Potamogalinae), occurs on the mainland. Morphological studies have generated conflicting hypotheses according to which both tenrecids and Malagassy tenrecs are either monophyletic or paraphyletic. Competing hypotheses have different implications for the biogeographic history

Christophe J. Douady; Francois Catzeflis; Diana J. Kao; Mark S. Springer; Michael J. Stanhope

2002-01-01

282

A method for quantifying biodiversity loss and its application to a 50-year record of deforestation across Madagascar  

Microsoft Academic Search

Madagascar is a top global conservation priority for high rates of deforestation and endemism. Deforestation has been extensive, but impacts of forest loss on biodiversity have not been well quantified, especially for nonvertebrates. We use generalized dissimilarity modeling (GDM) as a basis for estimating for- est biodiversity remaining at different points in time. We predict that 9.1% of species in

Thomas F. Allnutt; Simon Ferrier; Glenn Manion; George V. N. Powell; Taylor H. Ricketts; Brian L. Fisher; Grady J. Harper; Michael E. Irwin; Claire Kremen

2008-01-01

283

Endemism and diversification in freshwater insects of Madagascar revealed by coalescent and phylogenetic analysis of museum and field collections.  

PubMed

The biodiversity and endemism of Madagascar are among the most extraordinary and endangered in the world. This includes the island's freshwater biodiversity, although detailed knowledge of the diversity, endemism, and biogeographic origin of freshwater invertebrates is lacking. The aquatic immature stages of mayflies (Ephemeroptera) are widely used as bio-indicators and form an important component of Malagasy freshwater biodiversity. Many species are thought to be microendemics, restricted to single river basins in forested areas, making them particularly sensitive to habitat reduction and degradation. The Heptageniidae are a globally diverse family of mayflies (>500 species) but remain practically unknown in Madagascar except for two species described in 1996. The standard approach to understanding their diversity, endemism, and origin would require extensive field sampling on several continents and years of taxonomic work followed by phylogenetic analysis. Here we circumvent this using museum collections and freshly collected individuals in a combined approach of DNA taxonomy and phylogeny. The coalescent-based GMYC analysis of DNA barcode data (mitochondrial COI) revealed 14 putative species on Madagascar, 70% of which were microendemics. A phylogenetic analysis that included African and Asian species and data from two mitochondrial and four nuclear loci indicated the Malagasy Heptageniidae are monophyletic and sister to African species. The genus Compsoneuria is shown to be paraphyletic and the genus Notonurus is reinstalled for African and Malagasy species previously placed in Compsoneuria. A molecular clock excluded a Gondwanan vicariance origin and instead favoured a more recent overseas colonization of Madagascar. The observed monophyly and high microendemism highlight their conservation importance and suggest the DNA-based approach can rapidly provide information on the diversity, endemism, and origin of freshwater biodiversity. Our results underline the important role that museum collections can play in molecular studies, especially in critically endangered biodiversity hotspots like Madagascar where entire species or populations may go extinct very quickly. PMID:23261711

Vuataz, Laurent; Sartori, Michel; Gattolliat, Jean-Luc; Monaghan, Michael T

2013-03-01

284

Cover sequences at the northern margin of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The island of Madagascar is a collage of Precambrian, generally high-grade metamorphic basement domains, that are locally overlain by unmetamorphosed sedimentary rocks and poorly understood low-grade metasediments. In the Antalaha area of NE Madagascar, two distinct cover sequences rest on high-grade metamorphic and igneous basement rocks of the Archaean Antongil craton and the Neoproterozoic Bemarivo belt. The older of these two cover sequences, the Andrarona Group, consists of low-grade metasedimentary rocks. The younger sequence, the newly defined Ampohafana Formation, consists of unmetamorphosed sedimentary rocks. The Andrarona Group rests on Neoarchaean granites and monzogranites of the Antongil craton and consists of a basal metagreywacke, thick quartzites and an upper sequence of sericite-chlorite meta-mudstones, meta-sandstones and a volcaniclastic meta-sandstone. The depositional age of the volcaniclastic meta-sandstone is constrained in age by UPb laser-ablation ICP-MS analyses of euhedral zircons to 1875 8 Ma (2?). Detrital zircons of Archaean and Palaeoproterozoic age represent an input from the Antongil craton and a newly defined Palaeoproterozoic igneous unit, the Masindray tonalite, which underlies the Andrarona Group, and yielded a UPb zircon age of 2355 11 Ma (2?), thus constraining the maximum age of deposition of the basal part of the Andrarona Group. The Andrarona Group shows a low-grade metamorphic overprint in the area near Antalaha; illite crystallinity values scatter around 0.17?2? CuK?, which is within the epizone. The Ampohafana Formation consists of undeformed, polymict conglomerate, cross-bedded sandstone, and red mudstone. An illite crystallinity value of >0.25?2? CuK? obtained from the rocks is typical of the diagenetic zone. Occurrences of rhyodacite pebbles in the Ampohafana Formation and the intrusion of a basaltic dyke suggest a deposition in a WSW-ENE-trending graben system during the opening of the Indian Ocean in the Upper Cretaceous, that was characterized by extensive rhyolitic to basaltic magmatism along Madagascar's eastern coast.

Bauer, W.; Walsh, G.J.; De Waele, B.; Thomas, R.J.; Horstwood, M.S.A.; Bracciali, L.; Schofield, D.I.; Wollenberg, U.; Lidke, D.J.; Rasaona, I.T.; Rabarimanana, M.H.

2011-01-01

285

Phylogenetic and functional affinities of Babakotia (primates), a fossil lemur from northern Madagascar.  

PubMed Central

Recent paleontological expeditions to the Ankarana range of northern Madagascar have recovered the partial remains of four individuals of a newly recognized extinct lemur, Babakotia radofilai. Craniodental and postcranial material serve to identify Babakotia as a member of the palaeopropithecids (also including the extinct genera Palaeopropithecus, Archaeoindris, and Mesopropithecus). Living indrids form the sister group to this fossil clade. The postcranial anatomy indicates that Babakotia was a medium-sized (approximately 15 kg) indroid whose inferred positional behaviors were primarily slow climbing and hanging. Although it is probable that a leaping component typified the ancestral positional repertoire of all Malagasy lemurs, the mosaic nature of the locomotor skeleton of Babakotia further suggests that vertical climbing and hang-feeding rather than ricochetal leaping were primitive for indrids and palaeopropithecids and that the dramatic saltatory adaptations of the living indrids postdate the divergence of these two lineages. Images PMID:1924371

Jungers, W L; Godfrey, L R; Simons, E L; Chatrath, P S; Rakotosamimanana, B

1991-01-01

286

Reproductive activity of ruffed lemurs (Varecia variegata variegata) in a Madagascar rain forest.  

PubMed

Mating activity was observed during four breeding seasons in two groups of black and white ruffed lemurs (Varecia variegata variegata) living in lowland rain forest on Nosy Mangabe island, Madagascar. The onset of the May-July breeding season was signalled by behavioral changes in adult males. Males made forays outside their usual home ranges, were more aggressive to other males, and performed appetitive and other sex-specific behaviors more frequently. Females showed receptive and proceptive behaviors during a 1-2 day behavioral estrus. Ruffed lemurs mated monogamously, polyandrously, and polygynously. These observations do not support previous assertions that they live only in monogamous families. Limited evidence suggests females exercised mate choice and may have preferred familiar males. PMID:8512055

Morland, H S

1993-05-01

287

A new and aberrant species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Madagascar  

PubMed Central

Abstract In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia. PMID:25147450

Stocchino, Giacinta Angela; Sluys, Ronald; Manconi, Renata

2014-01-01

288

A new Ixodes species (Acari: Ixodidae), parasite of shrew tenrecs (Afrosoricida: Tenrecidae) in Madagascar.  

PubMed

Abstract :? A new tick species belonging to the African subgenus Afrixodes Morel, 1966 of the genus Ixodes Latreille, 1795, namely, Ixodes (Afrixodes) microgalei n. sp., is described. Females of this species are most similar to those of Ixodes colasbelcouri Arthur, 1957 and Ixodes nesomys Uilenberg & Hoogstraal, 1969. The female of the new species can easily be differentiated from I. colasbelcouri by a short spur on coxae IV, and from I. nesomys by longer spurs on coxae I and large punctations on its scutum. Ixodes microgalei is known only from the eastern humid forest of Madagascar, specifically in the Province of Antananarivo, where its females have been collected from several species of shrew tenrecs (Afrosoricida, Tenrecidae), namely, Microgale dobsoni Thomas, Microgale parvula Grandidier, and Microgale soricoides Jenkins. PMID:23901784

Apanaskevich, Dmitry A; Soarimalala, Voahangy; Goodman, Steven M

2013-12-01

289

Genome assembly and annotation of a Drosophila simulans strain from Madagascar.  

PubMed

Drosophila simulans is a close relative of the genetic model D.melanogaster. Its worldwide distribution in combination with the absence of segregating chromosomal inversions makes this species an increasingly attractive model to study the molecular signatures of adaptation in natural and experimental populations. In an effort to improve the genomic resources for D.simulans, we assembled and annotated the genome of a strain originating from Madagascar (M252), the ancestral range of D.simulans. The comparison of the M252 genome to other available D.simulans assemblies confirmed its high quality, but also highlighted genomic regions that are difficult to assemble with NGS data. The annotation of M252 provides a clear improvement with alternative splicing for 52% of the multiple-exon genes, UTRs for 70% of the genes, 225 novel genes and 781 pseudogenes being reported. We anticipate that the M252 genome will be a valuable resource for many research questions. PMID:24961367

Palmieri, Nicola; Nolte, Viola; Chen, Jun; Schltterer, Christian

2015-03-01

290

A necessarily complex model to explain the biogeography of the amphibians and reptiles of Madagascar.  

PubMed

Pattern and process are inextricably linked in biogeographic analyses, though we can observe pattern, we must infer process. Inferences of process are often based on ad hoc comparisons using a single spatial predictor. Here, we present an alternative approach that uses mixed-spatial models to measure the predictive potential of combinations of hypotheses. Biodiversity patterns are estimated from 8,362 occurrence records from 745 species of Malagasy amphibians and reptiles. By incorporating 18 spatially explicit predictions of 12 major biogeographic hypotheses, we show that mixed models greatly improve our ability to explain the observed biodiversity patterns. We conclude that patterns are influenced by a combination of diversification processes rather than by a single predominant mechanism. A 'one-size-fits-all' model does not exist. By developing a novel method for examining and synthesizing spatial parameters such as species richness, endemism and community similarity, we demonstrate the potential of these analyses for understanding the diversification history of Madagascar's biota. PMID:25297804

Brown, Jason L; Cameron, Alison; Yoder, Anne D; Vences, Miguel

2014-01-01

291

Population Genetic Structure and Isolation by Distance of Helicobacter pylori in Senegal and Madagascar  

PubMed Central

Helicobacter pylori has probably infected the human stomach since our origins and subsequently diversified in parallel with their human hosts. The genetic population history of H. pylori can therefore be used as a marker for human migration. We analysed seven housekeeping gene sequences of H. pylori strains isolated from 78 Senegalese and 24 Malagasy patients and compared them with the sequences of strains from other geographical locations. H. pylori from Senegal and Madagascar can be placed in the previously described HpAfrica1 genetic population, subpopulations hspWAfrica and hspSAfrica, respectively. These 2 subpopulations correspond to the distribution of Niger-Congo speakers in West and most of subequatorial Africa (due to Bantu migrations), respectively. H. pylori appears as a single population in Senegal, indicating a long common history between ethnicities as well as frequent local admixtures. The lack of differentiation between these isolates and an increasing genetic differentiation with geographical distance between sampling locations in Africa was evidence for genetic isolation by distance. The Austronesian expansion that started from Taiwan 5000 years ago dispersed one of the 10 subgroups of the Austronesian language family via insular Southeast Asia into the Pacific and Madagascar, and hspMaori is a marker for the entire Austronesian expansion. Strain competition and replacement of hspMaori by hpAfrica1 strains from Bantu migrants are the probable reasons for the presence of hspSAfrica strains in Malagasy of Southeast Asian descent. hpAfrica1 strains appear to be generalist strains that have the necessary genetic diversity to efficiently colonise a wide host spectrum. PMID:24498084

Linz, Bodo; Vololonantenainab, Clairette Romaine Raharisolo; Seck, Abdoulaye; Carod, Jean-Franois; Dia, Daouda; Garin, Benoit; Ramanampamonjy, Rado Manitrala; Thiberge, Jean-Michel; Raymond, Josette; Breurec, Sebastien

2014-01-01

292

Geochronology and 4+ thermometry of ultrahigh-temperature (UHT) metamorphism in southern Madagascar  

NASA Astrophysics Data System (ADS)

Ultrahigh temperature (UHT) metamorphism--regional metamorphism at >900 C--in a collisional setting requires some combination of: i) unusually radiogenic crust, ii) advection of heat by magmatism, iii) conduction of mantle-derived heat, and iv) shear heating. The Neoproterozoic continental collision zone exposed in Madagascar provides a good opportunity to investigate these potential causes; we use three 4+ thermometers (Zr-in-rutile, Ti-in-zircon, and Ti-in-quartz) and U/Th-Pb geochronology of monazite and zircon to evaluate the magnitude, timing, and duration of UHT metamorphism in southern Madagascar. U-Pb dates from metamorphic monazite and zircon with complex intragrain (re)crystallization textures range from ~600 Ma to ~500 Ma. Zircon and monazite with HREE depletion and dates of 600-540 Ma suggest (re)crystallization in the presence of garnet. All monazite shows negative Eu anomalies (compatible with the presence of plagioclase), but monazite with dates from ~570 to ~530 Ma has more pronounced anomalies. Zr-in-rutile temperatures span 700 to 960 C and Ti-in-quartz temperatures span 600 to 950 C. The UHT metamorphism is assumed to postdate both the accretion of an arc terrane to West Gondwana at ~600 Ma and the suturing of East and West Gondwana prior to ~570 Ma. The 40 Myr between distinct episodes of alkali plutonism at ~570 Ma (deformed) and ~530 Ma (nondeformed) coincide with more-negative Eu anomalies in monazite, and may reflect the period of orogenesis associated with UHT metamorphism. The measured K, Th, and U contents of rocks within the UHT domain [GAF-BGR, 2008] indicate an average heat production of >5 ?W/m3. This is sufficient to produce UHT metamorphism in 60-km thick crust within 40 Myr.

Horton, F.; Hacker, B. R.; Kylander-Clark, A. R.

2013-12-01

293

Defining and explaining tropical deforestation: shifting cultivation and population growth in colonial Madagascar (1896-1940).  

PubMed

The case study of deforestation in Madagascar demonstrated how deforestation is a complex phenomenon that reflects interconnections between land-based resources, human groups, and global political economy; specifically, there is a link between changing land use practices affecting shifting cultivation and tropical deforestation. The general development model of exponential population growth and shifting cultivation causing deforestation and environmental degradation is too simplified, places undue blame on the victims, and isolates shifting cultivation practices from the reality of land use patterns in specific places at specific times. Problematic also is the way definition, delimitation, and discussion of environmental problems shapes possible solutions. This analysis suggests a theoretical view that links reconstructed regional geography with political ecology. The assertion is that deforestation is historically based on multiple social processes within Madagascar. Land use practices and resource access decisions during the colonial period affected land management and degradation. The colonial state policy played a role in the destruction of tropical flora by fire, shifting cultivation, and grazing, and the responses of Europeans and Malagasys. Context and multiplicity of motivations and practices were key. A review was presented of reconstructed regional geography and political ecology and global tropical deforestation. The description of the political economy of deforestation during colonial times focused on the movement of population into the forests after 1896 and French annexation. Famine resulted. Shifting cultivation laws were passed between 1881 and 1913, due to the desire for rational forest resource management. Ecologically and socially these rules were difficult to enforce; there were resistance due to the threat of the elimination of subsistence living for wage work. Destructive logging practices and forest product extraction after 1921 are described. During 1900-1941, population was below or at replacement level, but the government still blamed Malagasys. Shifting cultivation meant different things to the subsistence farmers, the state, and international agencies. Denial of context promotes an ideology of repression, fuels fear and prejudice, and promotes the wrong solutions. PMID:12318844

Jarosz, L

1993-10-01

294

Madagascar Highland erosion: What can we learn from the archive precipitation data?  

NASA Astrophysics Data System (ADS)

In Madagascar, soil erosion is significant even when it is compared to world averages, resulting in special geomorphic forms known as lavakas appearing in the Highland regions of the island. The development of these features is due to rather unique multifactorial environmental conditions. Among many factors (geology, soil composition, human influence, etc.) the spatial and temporal distribution of precipitation is a key factor. The presence of the dry and wet season seems to be responsible for the enhanced generation of small cracks that might eventually lead to the development of a gully. However, the way of the development of such gully erosions are unknown. To what extent of the actual precipitation pattern to what extent the weather contributes to the aforementioned phenomenon has not yet been studied in great detail. The aim of our research is to study the climatic and weather conditions of lavaka-prone areas for the last decades. The typical cyclonal pattern affects the Madagascar Highlands in various ways. The precipitation and the soil moisture data show that the spatial distribution can be correlated with the appearance of lavakas to a given extent, however the local distribution cannot be explained only based on the precipitation pattern. The severity of the wet season varies strongly in the various decades leading to different precipitation maxima in January-March period. In general the effectiveness of the gully erosion is thought to be highly enhanced if the run-off of the area show large temporal variations. According to our studies this variability is quite high in certain seasons, and, despite of the low spatial resolution, related to the lavaka-prone areas. However, neither the amount of the precipitation, nor the variability alone cannot explain the high variation found in the spatial density and length distribution. Further multidisciplinary studies are necessary to draw conclusions about lavaka formation and describe the process of lavaka development. This is ILARG-contribution Nr. 11.

Imola Szab, Amanda; Raveloson, Andrea; Szkely, Balzs

2014-05-01

295

Forest Management Devolution: Gap Between Technicians' Design and Villagers' Practices in Madagascar  

NASA Astrophysics Data System (ADS)

In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.

Rives, Fanny; Carrire, Stphanie M.; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole

2013-10-01

296

Bulinus species on Madagascar: molecular evolution, genetic markers and compatibility with Schistosoma haematobium.  

PubMed

Of the four species of Bulinus found on Madagascar, three species: B. obtusispira, B. liratus and B. bavayi are endemic while the fourth, B. forskalii, is probably a recent introduction from the African mainland. The evolutionary relationships of these species with Bulinus species from Africa were studied by phylogenetic analysis of DNA sequence variation at two mitochondrial loci: cytochrome oxidase subunit I (COI) and large ribosomal subunit (LSU) or 16S. The observed levels of nucleotide divergence within Bulinus were substantial but may underestimate the true levels as there was evidence of 'saturation' of transitional substitutions at both loci. A putative secondary structure model for the sequenced segment of the 16S was developed. Subsequent phylogenetic analysis using transversional changes only for both loci, showed that there were contrasting levels of divergence within the four species groups. B. obtusispira was consistently placed within the B. africanus group, appearing ancestral to this group and was closest to the basal node within Bulinus. Together with B. bavayi, the two species appear to have been isolated on Madagascar for a long time, contrasting with both B. liratus and B. forskalii that appear more recent colonisers; however, estimate of exact times of divergence is problematic. A PCR-RFLP assay was developed to enable identification and discrimination of B. obtusispira and B. liratus using discriminatory variation within the COI. To enable population genetic analysis within B. obtusispira, microsatellite markers were developed using an enrichment method and 8 primer pairs are reported. Laboratory infection experiments using Madasgacan S. haematobium from the Mahabo area showed that certain populations of B. obtusispira, B. liratus and B. bavayi were compatible. PMID:11769288

Stothard, J R; Brmond, P; Andriamaro, L; Sellin, B; Sellin, E; Rollinson, D

2001-01-01

297

[Identification of communities endemic for urinary bilharziosis by the "Lot Quality Assurance Sampling" method in Madagascar].  

PubMed

Reduction of morbidity is the main component in the National Schistosomiasis Control Program in Madagascar. The lot quality assurance sampling (LQAS) method has previously been shown as a useful tool in assessment of immunization coverage. A study was carried in the western part of Madagascar aiming to evaluate the applicability of the method in measuring the level of Schistosoma haematobium endemic level in different communities. Parasitological examination of urine samples from 1,124 children aged 5 to 19 years from 12 different schools by use of filtration technique constituted the reference in determining the prevalence. Three schools were found hyper-endemic (prevalence more than 60%), 5 schools were intermediate-endemic (prevalence between 30 to 59%), and 4 were hypo-endemic (prevalence less than 30%). Those figures indicate a heterogeneous distribution of S. haematobium in the study area. A sampling plan (16.6) was then tested in the same area while other sampling plans were simulated in the laboratory. School teachers randomized under supervision the children to participate in this study and collected urine samples. All sampling plans (16.6), (14.5), (12.4), (10.3), (8.2), (6.1) et (4.0) allowed correct identification of hyper-endemic and hypo-endemic areas. Misclassifications occurred frequently for intermediate-endemic areas. The study confirms that the LQAS method by use of a (16.6) sampling plan constitute a valuable tool for large scale screening of hyper-endemic areas for therapeutic intervention as part of the control program. The study has also shown that school teachers may offer a potential source of manpower locally in such screening operations. PMID:12471747

Rabarijaona, L P; Andriamaroson, B J; Ravaoalimalala, V E; Ravoniarimbinina, P; Migliani, R

2001-01-01

298

Lost in translation: conflicting views of deforestation, land use and identity in western Madagascar.  

PubMed

This paper focuses on the interplay between environmental narratives, identity politics and the management of forest resources in Madagascar. While efforts to conserve the island's biological diversity have centred primarily on the designation of protected areas, policies have increasingly focused on local communities. The experiences of the last 20 years have shown that community-based approaches to conservation offer considerable challenges due to the complex politics of natural resource use, which involve multiple and diverse stakeholders, often with very different and sometimes conflicting values. In this paper, I focus on the environmental perceptions and values of two groups in the Central Menabe region of western Madagascar conservation organisations and rural households revealing a contrasting set of views regarding the region's forest. I show that the conservation discourse has changed over time, increasingly emphasising the biological diversity of the region's tropical dry-deciduous forest and prioritising non-consumptive uses of natural resources. Although policy has changed in response to changing values, I show that it has been underpinned by the notion that hatsake (slash-and-burn agriculture) is an irrational practice driven by necessity rather than choice. Policy has thus sought to provide livelihood alternatives, firstly through forestry, then through changes in cultivation and increasingly through tourism. This misunderstands the local view of the forest, which sees hatsake as a way to make the land productive, as long as it is carried out responsibly according to local fady (taboos). As well as facing problems of translating conservation goals into local values and misunderstanding the motives for forest clearance, policy has been based on a narrative that attaches particular land use practices to ethnic identities. I argue that this ignores the history and fluid reality of both identity and land use. PMID:22413174

Scales, Ivan R

2012-01-01

299

Early-warning health and process indicators for sentinel surveillance in Madagascar 2007-2011  

PubMed Central

Background: Epidemics pose major threats in resource-poor countries, and surveillance tools for their early detection and response are often inadequate. In 2007, a sentinel surveillance system was established in Madagascar, with the aim of rapidly identifying potential epidemics of febrile or diarrhoeal syndromes and issuing alerts. We present the health and process indicators for the five years during which this system was constructed, showing the spatiotemporal trends, early-warning sign detection capability and process evaluation through timely analyses of high-quality data. Methods: The Malagasy sentinel surveillance network is currently based on data for fever and diarrhoeal syndromes collected from 34 primary health centres and reported daily via the transmission of short messages from mobile telephones. Data are analysed daily at the Institut Pasteur de Madagascar to make it possible to issue alerts more rapidly, and integrated process indicators (timeliness, data quality) are used to monitor the system. Results: From 2007 to 2011, 917,798 visits were reported. Febrile syndromes accounted for about 11% of visits annually, but the trends observed differed between years and sentinel sites. From 2007 to 2011, 21 epidemic alerts were confirmed. However, delays in data transmission were observed (88% transmitted within 24 hours in 2008; 67% in 2011) and the percentage of forms transmitted each week for validity control decreased from 99.9% in 2007 to 63.5% in 2011. Conclusion: A sentinel surveillance scheme should take into account both epidemiological and process indicators. It must also be governed by the main purpose of the surveillance and by local factors, such as the motivation of healthcare workers and telecommunication infrastructure. Permanent evaluation indicators are required for regular improvement of the system. PMID:25598869

Rajatonirina, Soatiana; Rakotomanana, Fanjasoa; Randrianasolo, Laurence; Razanajatovo, Norosoa Harline; Andriamandimby, Soa Fy; Ravolomanana, Lisette; Randrianarivo-Solofoniaina, Armand Eugne; Reynes, Jean-Marc; Piola, Patrice; Finlay-Vickers, Alyssa; Heraud, Jean-Michel; Richard, Vincent

2014-01-01

300

Tracing Arab-Islamic inheritance in Madagascar: study of the Y-chromosome and mitochondrial DNA in the Antemoro.  

PubMed

Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar. PMID:24278350

Capredon, Mlanie; Brucato, Nicolas; Tonasso, Laure; Choesmel-Cadamuro, Valrie; Ricaut, Franois-Xavier; Razafindrazaka, Harilanto; Rakotondrabe, Andriamihaja Bakomalala; Ratolojanahary, Mamisoa Adelta; Randriamarolaza, Louis-Paul; Champion, Bernard; Dugoujon, Jean-Michel

2013-01-01

301

Petrogenesis of a basanitetephritephonolite volcanic suite in the Bobaomby (Cap dAmbre) peninsula, northern Madagascar  

Microsoft Academic Search

The Late Cenozoic Bobaomby volcanic field is located in the northernmost Madagascar, in the area north of the Massif dAmbre. It comprises widely scattered outcrops of lava flows, dykes, scoria cones, tuff rings and plugs, emplaced in the Meso-Cenozoic sedimentary rocks of the Diego Basin. The Bobaomby rocks range in composition from Mg-rich, sodic basanite to phonolite (MgO from 13

L. Melluso; V. Morra; H. Riziky; J. Veloson; M. Lustrino; L. Del Gatto; V. Modeste

2007-01-01

302

The structure of the lithosphere and asthenosphere beneath Mozambique and Madagascar from combined surface wave and ambient noise tomography  

NASA Astrophysics Data System (ADS)

We present results based on applying the two-plane wave method to the observed amplitude and phase of fundamental mode surface waves from the NSF-funded MACOMO IRIS PASSCAL broadband seismometer deployment in Madagascar and Mozambique. The two-plane wave method (Forsyth and Li, 2005) involves modeling arriving surface waves by a two-plane-wave field. Combining this method with ambient noise will allow the joint inversion of phase velocities from 5 to 180 s, to generate a high-resolution 3-D shear wave velocity model from the surface to a depth of ~200 km beneath Madagascar, Mozambique and the surrounding regions. Using the two-plane wave method, the phase and amplitude of fundamental mode Rayleigh waves from distant earthquakes recorded at MACOMO are inverted for 2-D phase velocity maps at periods from 18 to 180 s. The ambient noise method (a separate study) is limited to short periods and therefore it is sensitive only to the crust and uppermost mantle structure. The 3-D shear-wave velocity structure beneath East Africa (Mozambique and Madagascar) where the East African Orogeny was instrumental in the amalgamation of Gondwana (~540 Ma) is investigated by using the implicit relation between phase-velocity dispersion and shear-wave structure. The phase velocities, at selected periods and at each node of the phase velocity maps, are inverted for a 1-D structure; the 1-D models at each node form the 3-D shear-wave model. Phase-velocity tomographic images show 2-D lateral variations in phase velocities at each period. Preliminary results show that above periods of 124 sec we noticed a rapid vertical transition to low phase velocities beneath southern Madagascar.

Shore, P.; Aleqabi, G. I.; Wysession, M. E.; Pratt, M. J.; Wiens, D. A.; Nyblade, A.; Rambolamana, G.; Rakotondraibe, T.; Sy Tanjona Andriampenomanana ny Ony, F.

2013-12-01

303

Sur l'association de Phoronis australis (Phoronida) avec Cerianthus maua (Ceriantharia) dans les zones rcifales de Madagascar  

Microsoft Academic Search

The occurrence of Phoronis australisHaswell in the tubewalls of Cerianthus mauaCarlgren at Madagascar allows us to describe the taxonomic characteristics of both species and to deal with ecological aspects of the bottoms colonized. The tube wall of C. maua may be divided into 5 distinct layers. P. australis builds his own tube (whose position in the cerianthid-tube is studied): the

C. C. ElvIIG; C. Herberts; B. A. Thomassin

1972-01-01

304

Top soil radioactivity assessment in a high natural radiation background area: The case of Vinaninkarena, AntsirabeMadagascar  

Microsoft Academic Search

The village of Vinaninkarena, Antsirabe, Madagascar (4702?40?E, 1957?17?S) is located in a high natural radioactivity area. In order to evaluate the natural radionuclide content in soil, sampling was done on-site by the transect method (85 soil samples) and off-site through transects across and beyond the region (up to a range of 100km), to determine the natural radioactivity variation within vs.

Naivo Rabesiranana; Martin Rasolonirina; Franck Terina; Asivelo F. Solonjara; Raoelina Andriambololona

2008-01-01

305

Density estimates of two endangered nocturnal lemur species from northern Madagascar: new results and a comparison of commonly used methods.  

PubMed

Very little information is known of the recently described Microcebus tavaratra and Lepilemur milanoii in the Daraina region, a restricted area in far northern Madagascar. Since their forest habitat is highly fragmented and expected to undergo significant changes in the future, rapid surveys are essential to determine conservation priorities. Using both distance sampling and capture-recapture methods, we estimated population densities in two forest fragments. Our results are the first known density and population size estimates for both nocturnal species. In parallel, we compare density results from four different approaches, which are widely used to estimate lemur densities and population sizes throughout Madagascar. Four approaches (King, Kelker, Muller and Buckland) are based on transect surveys and distance sampling, and they differ from each other by the way the effective strip width is estimated. The fifth method relies on a capture-mark-recapture (CMR) approach. Overall, we found that the King method produced density estimates that were significantly higher than other methods, suggesting that it generates overestimates and hence overly optimistic estimates of population sizes in endangered species. The other three distance sampling methods provided similar estimates. These estimates were similar to those obtained with the CMR approach when enough recapture data were available. Given that Microcebus species are often trapped for genetic or behavioral studies, our results suggest that existing data can be used to provide estimates of population density for that species across Madagascar. PMID:22311681

Meyler, Samuel Viana; Salmona, Jordi; Ibouroi, Mohamed Thani; Besolo, Aubin; Rasolondraibe, Emmanuel; Radespiel, Ute; Rabarivola, Clment; Chikhi, Lounes

2012-05-01

306

Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.).  

PubMed

The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n=51 landraces), levels of toxic elements (e.g., total mercury, methylmercury, arsenic and cadmium) as well as essential micronutrients (e.g., zinc and selenium) were uniformly low, indicating potentially both positive and negative health effects. Aside from manganese (Wilcoxon rank sum, p<0.01), no significant differences in concentrations for all trace elements were observed between rice with red bran (n=20) and brown bran (n=31) (Wilcoxon rank sum, p=0.06-0.91). Compared to all elements in rice, rubidium (i.e., tracer for phloem transport) was most positively correlated with methylmercury (Pearson's r=0.33, p<0.05) and total mercury (r=0.44, p<0.05), while strontium (i.e., tracer for xylem transport) was least correlated with total mercury and methylmercury (r<0.01 for both), suggesting inorganic mercury and methylmercury were possibly more mobile in phloem compared to xylem. PMID:25463705

Rothenberg, Sarah E; Mgutshini, Nomathamsanqa L; Bizimis, Michael; Johnson-Beebout, Sarah E; Ramanantsoanirina, Alain

2014-10-23

307

Stable carbon isotope values document how a Late Holocene expansion in grasslands impacted vertebrates in northwestern Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is home to some of the world's most distinctive plants and animals. Unfortunately, forest loss and habitat degradation has had a dramatic impact on both floral and faunal communities. Here we use carbon isotope values in radiocarbon-dated bones to examine how the vertebrate community at Anjohibe Cave, northwestern Madagascar, responded to a Late Holocene increase in C4 grass abundance. Our data demonstrate that major changes in the vegetation and animal community are recent phenomena at Anjohibe. Extinct lemurs and hippopotamuses were present until ca. 1500 years ago. These taxa relied exclusively on C3 resources. Locally extirpated fauna were present until 300 years ago. The majority of these species also relied on C3 resources. Their presence strongly suggests that the region surrounding the cave was more wooded than it is now, possibly as recently as 300 years ago. All introduced individuals are modern. Rats (Rattus sp.), shrews (Suncus murinus), and the giant frog Hoplobatrachus cf. tigrinus, have remarkably high carbon isotope values, implicating substantial ingestion of C4 foods. It is possible that grass abundance has increased dramatically in the past 100 years. Alternatively, opportunistically granivorous rats and shrews may selectively consume seeds from C4 grasses. In agreement with previous studies, stable isotope data reveal details of vegetation and faunal turnover in Northwestern Madagascar. Grasses have increased, forest dwelling species have vanished, and introduced taxa are exploiting a novel niche.

Crowley, B. E.; Samonds, K.

2012-12-01

308

Deforestation and Rice: Using Methods in Modeling and Remote Sensing to Project Patterns of Forest Change in Eastern Madagascar  

NASA Astrophysics Data System (ADS)

In the species rich tropics, forest conservation is often eclipsed by anthropogenic disturbance, resulting in a heightened need for an accurate assessment of biomass and the gaining of predictive capability before these ecosystems disappear. The combination of multi-temporal remote sensing data, field data and forest growth modeling to quantify carbon stocks and flux is therefore of great importance. In this study, we utilize these methods to (1) improve forest biomass and carbon flux estimates for the study region in Eastern Madagascar, and (2) initialize an individual-based growth model that incorporates the anthropogenic factors causing deforestation to project ecosystem response to future environmental change. Recent studies have shown that there is a direct correlation between the international rice market and rates of deforestation in tropical countries such as Madagascar (see Minten et al., 2006). Further, although law protects the remaining forest areas, dictatorships and recent political unrest have lead to poor or non-existent enforcement of precious wood and forest protection over the past 35 years. Our approach combined multi-temporal remote sensing analysis and ecological modeling using a theoretical and mathematical approach to assess biomass change and to understand how tree growth and life history (growth response patterns) relate to past and present economic variability in Madagascar forests of the eastern Toamasina region. We measured rates of change of deforestation with respect to politics and the price of rice by classifying and comparing biomass using 30m Landsat during 5 political regime time periods (1985-1992, 1993-1996, 1997-2001, 2002-2008, 2009 to present). Forest biomass estimations were calibrated using forest inventory data collected over 3 growing seasons over the study region (130 small circular plots in primary forest). This information was then built into the previously parameterized (Armstrong et al., in prep and Fischer et al in review) Madagascar FORMIX3 Model (see Huth and Ditzer, 2000) by incorporating rice economy, selective logging and political stability modules into the model to control certain species groups (i.e. selective harvest) and fire frequency (encroachment). The improved FORMIX3 model was then used to investigate and project forest growth response to a variety of impact scenarios ranging from an increase in overall deforestation to a decrease in deforestation and increase in protection enforcement. Our findings showed a significant positive correlation between increasing deforestation rates and higher local rice prices due to political regime and international market factors. This research resulted in the first quantitative analysis of the relationship between the international rice market and local land-use in terms of slash and burn agriculture, illegal logging of precious hardwood in Madagascar.

Armstrong, A. H.; Fatoyinbo, T. E.; Fischer, R.; Huth, A.; Shugart, H. H.

2013-12-01

309

Campylobacter infection in a cohort of rural children in Moramanga, Madagascar  

PubMed Central

Background Campylobacter infection is the most common cause of bacterial gastroenteritis in developing countries, including Madagascar. Reports of pathogenicity have not been consistent and repeated exposures over time seem to lead to the development of protective immunity in developing areas. We conducted this study to support evidence for these hypotheses by exploring the association between infection and age, the reoccurrence of infection and the pathogenicity of Campylobacter. Methods We carried out a community-based longitudinal study of children under the age of 24months in two rural villages in Moramanga, Madagascar. Children were visited twice a week and a stool specimen was collected in cases of diarrhoea. Stools specimens were collected bimonthly from all children enrolled, regardless of symptoms. Children were followed-up until the age of 36months. Results Between January 2010 and May 31st 2012, 508 children were included in the cohort. We detected 319 episodes of Campylobacter infection in total, and 43.3% (n?=?220) of the children had at least one episode of intestinal Campylobacter infection. The rate of Campylobacter isolation from stool specimens was 9.3%. The annual incidence rate for symptomatic Campylobacter infection was 0.05 episodes/child. The probability of Campylobacter infection was highest between the ages of six and 23months. Taking children under six months of age as the reference group, the age-specific odds ratio for the association was 5.0 (95% CI: 2.9-8.6) for children aged six to 11months, 5.7 (95% CI: 3.3-10.0) for children aged 12 to 17months and 3.3 (95% CI: 1.8-5.8) for children aged 18 to 23months. A second episode of infection occurred 63days after the first episode in children with primary infections, and after 137days in children with multiple infections (p?

2014-01-01

310

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009  

PubMed Central

Background In Madagascar, despite an influenza surveillance established since 1978, little is known about the etiology and prevalence of viruses other than influenza causing influenza-like illnesses (ILIs). Methodology/Principal Findings From July 2008 to June 2009, we collected respiratory specimens from patients who presented ILIs symptoms in public and private clinics in Antananarivo (the capital city of Madagascar). ILIs were defined as body temperature ?38C and cough and at least two of the following symptoms: sore throat, rhinorrhea, headache and muscular pain, for a maximum duration of 3 days. We screened these specimens using five multiplex real time Reverse Transcription and/or Polymerase Chain Reaction assays for detection of 14 respiratory viruses. We detected respiratory viruses in 235/313 (75.1%) samples. Overall influenza virus A (27.3%) was the most common virus followed by rhinovirus (24.8%), RSV (21.2%), adenovirus (6.1%), coronavirus OC43 (6.1%), influenza virus B (3.9%), parainfluenza virus-3 (2.9%), and parainfluenza virus-1 (2.3%). Co-infections occurred in 29.4% (69/235) of infected patients and rhinovirus was the most detected virus (27.5%). Children under 5 years were more likely to have one or more detectable virus associated with their ILI. In this age group, compared to those ?5 years, the risk of detecting more than one virus was higher (OR?=?1.9), as was the risk of detecting of RSV (OR?=?10.1) and adenovirus (OR?=?4.7). While rhinovirus and adenovirus infections occurred year round, RSV, influenza virus A and coronavirus OC43 had defined period of circulation. Conclusions In our study, we found that respiratory viruses play an important role in ILIs in the Malagasy community, particularly in children under 5 years old. These data provide a better understanding of the viral etiology of outpatients with ILI and describe for the first time importance of these viruses in different age group and their period of circulation. PMID:21390235

Razanajatovo, Norosoa Harline; Richard, Vincent; Hoffmann, Jonathan; Reynes, Jean-Marc; Razafitrimo, Girard Marcellin; Randremanana, Rindra Vatosoa; Heraud, Jean-Michel

2011-01-01

311

Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region  

PubMed Central

The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed. PMID:22826244

Qumr, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Louns

2012-01-01

312

Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region.  

PubMed

The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species' habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed. PMID:22826244

Qumr, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Louns

2012-08-01

313

Etiologies des pleursies exsudatives: propos de 424 cas Madagascar  

PubMed Central

Introduction La pleursie constitue un motif frquent de consultation en pneumologie. Notre travail a pour objectif de dterminer les tiologies des pleursies exsudatives afin d'en faciliter les dmarches tiologiques. Mthodes Il s'agit d'une tude rtrospective ralise chez des patients ayant une pleursie exsudative et bnficiant une biopsie pleurale l'aveugle l'aide de l'aiguille de Castelain, pendant une priode de 5 ans (2005 2009). Rsultats Parmi les 424 patients inclus, 259 hommes (61,08%) et 165 femmes (38,91%) taient individualiss. Les pleursies taient d'origine tuberculeuse dans 298 cas (70, 28%), mtastatique dans 63 cas (14,85%), inflammation non spcifique dans 51 cas (12,02%). Des fibres musculaires stries taient biopsies dans 12 cas (2,83%). Conclusion La biopsie pleurale occupe une place prpondrante dans la recherche tiologique des pleursies d'exsudatives Madagascar o la tuberculose svit encore en mode endmique. PMID:22145067

Rakotoson, Jolson Lovaniaina; Andrianasolo, Radonirina Lazasoa; Rakotomizao, Robert Jocelyn; Vololontiana, Marie Danielle Hanta; Ravahatra, Kiady; Rajaoarifetra, Jobeline; Andrianarisoa, Christophe Flix Ange

2011-01-01

314

Comparative and population mitogenomic analyses of Madagascar's extinct, giant 'subfossil' lemurs.  

PubMed

Humans first arrived on Madagascar only a few thousand years ago. Subsequent habitat destruction and hunting activities have had significant impacts on the island's biodiversity, including the extinction of megafauna. For example, we know of 17 recently extinct 'subfossil' lemur species, all of which were substantially larger (body mass ?11-160kg) than any living population of the ?100 extant lemur species (largest body mass ?6.8kg). We used ancient DNA and genomic methods to study subfossil lemur extinction biology and update our understanding of extant lemur conservation risk factors by i) reconstructing a comprehensive phylogeny of extinct and extant lemurs, and ii) testing whether low genetic diversity is associated with body size and extinction risk. We recovered complete or near-complete mitochondrial genomes from five subfossil lemur taxa, and generated sequence data from population samples of two extinct and eight extant lemur species. Phylogenetic comparisons resolved prior taxonomic uncertainties and confirmed that the extinct subfossil species did not comprise a single clade. Genetic diversity estimates for the two sampled extinct species were relatively low, suggesting small historical population sizes. Low genetic diversity and small population sizes are both risk factors that would have rendered giant lemurs especially susceptible to extinction. Surprisingly, among the extant lemurs, we did not observe a relationship between body size and genetic diversity. The decoupling of these variables suggests that risk factors other than body size may have as much or more meaning for establishing future lemur conservation priorities. PMID:25523037

Kistler, Logan; Ratan, Aakrosh; Godfrey, Laurie R; Crowley, Brooke E; Hughes, Cris E; Lei, Runhua; Cui, Yinqiu; Wood, Mindy L; Muldoon, Kathleen M; Andriamialison, Haingoson; McGraw, John J; Tomsho, Lynn P; Schuster, Stephan C; Miller, Webb; Louis, Edward E; Yoder, Anne D; Malhi, Ripan S; Perry, George H

2015-02-01

315

Complex epidemiology and zoonotic potential for Cryptosporidium suis in rural Madagascar.  

PubMed

Cryptosporidium spp. is the most important parasitic diarrheal agent in the world, is among the top four causes of moderate-to-severe diarrheal disease in young children in developing nations, and is problematic as an opportunistic co-infection with HIV. In addition, Cryptosporidium is a persistent challenge for livestock production. Despite its zoonotic potential, few studies have examined the ecology and epidemiology of this pathogen in rural systems characterized by high rates of overlap among humans, domesticated animals, and wildlife. To improve our understanding of the zoonotic potential of Cryptosporidium species in the rural tropics, we screened humans, livestock, peridomestic rodents, and wildlife using PCR-RFLP and sequencing-based approaches to distinguish species of Cryptosporidium in rural southeastern Madagascar. Cryptosporidium of multiple species/genotypes were apparent in this study system. Interestingly, C. suis was the dominant species of Cryptosporidium in the region, infecting humans (n=1), cattle (n=18), pigs (n=3), and rodents (n=1). The broad species range of C. suis and the lack of common cattle Cryptosporidium species (Cryptosporidium parvum and Cryptosporidium andersoni) in this system are unique. This report represents the fifth confirmed case of C. suis infection in humans, and the first case in Africa. Few rural human and livestock populations have been screened for Cryptosporidium using genus-specific genotyping methods. Consequently, C. suis may be more widespread in human and cattle populations than previously believed. PMID:25481280

Bodager, Jonathan R; Parsons, Michele B; Wright, Patricia C; Rasambainarivo, Fidisoa; Roellig, Dawn; Xiao, Lihua; Gillespie, Thomas R

2015-01-15

316

Insights on the evolution of plant succulence from a remarkable radiation in Madagascar (Euphorbia).  

PubMed

Patterns of adaptation in response to environmental variation are central to our understanding of biodiversity, but predictions of how and when broad-scale environmental conditions such as climate affect organismal form and function remain incomplete. Succulent plants have evolved in response to arid conditions repeatedly, with various plant organs such as leaves, stems, and roots physically modified to increase water storage. Here, we investigate the role played by climate conditions in shaping the evolution of succulent forms in a plant clade endemic to Madagascar and the surrounding islands, part of the hyper-diverse genus Euphorbia (Euphorbiaceae). We used multivariate ordination of 19 climate variables to identify links between particular climate variables and three major forms of succulence-succulent leaves, cactiform stem succulence, and tubers. We then tested the relationship between climatic conditions and succulence, using comparative methods that account for shared evolutionary history. We confirm that plant water storage is associated with the two components of aridity, temperature, and precipitation. Cactiform stem succulence, however, is not prevalent in the driest environments, countering the widely held view of cactiforms as desert icons. Instead, leaf succulence and tubers are significantly associated with the lowest levels of precipitation. Our findings provide a clear link between broad-scale climatic conditions and adaptation in land plants, and new insights into the climatic conditions favoring different forms of succulence. This evidence for adaptation to climate raises concern over the evolutionary future of succulent plants as they, along with other organisms, face anthropogenic climate change. PMID:24852061

Evans, Margaret; Aubriot, Xavier; Hearn, David; Lanciaux, Maxime; Lavergne, Sebastien; Cruaud, Corinne; Lowry, Porter P; Haevermans, Thomas

2014-09-01

317

Anatomical Correlates to Nectar Feeding among the Strepsirrhines of Madagascar: Implications for Interpreting the Fossil Record  

PubMed Central

One possible ecological scenario for the origin of primates is the archaic pollination and coevolution hypothesis. Its proponents contend that the consumption of nectar by some early primates and the resulting cross-pollination is an example of coevolution that drove adaptive radiations in some primates. This hypothesis is perhaps ecologically sound, but it lacks the morphology-behavior links that would allow us to test it using the fossil record. Here we attempt to identify cranial adaptations to nectar feeding among the strepsirrhines of Madagascar in order to provide such links. Many Malagasy strepsirrhines are considered effective cross-pollinators of the flowers they feed from, and nectar consumption represents as much as 75% of total feeding time. Previous studies identified skeletal correlates to nectar feeding in the crania of nonprimate mammals; from these, nine cranial measurements were chosen to be the focus of the present study. Results indicate that Cheirogaleus, Varecia, and Eulemur mirror other nectar-feeding mammals in having elongated crania and/or muzzles. These strepsirrhines might be effective cross-pollinators, lending support to the coevolution hypothesis. PMID:22567292

Muchlinski, Magdalena N.; Perry, Jonathan M. G.

2011-01-01

318

Geometry and kinematics of the late Proterozoic Angavo Shear Zone, Central Madagascar: Implications for Gondwana Assembly  

NASA Astrophysics Data System (ADS)

This paper documents the 20 to 60 km wide N-S trending Angavo Shear Zone (ASZ) in central Madagascar and its tectonic implications by examining its structural styles, kinematics and geometry. Our study indicates that the ASZ is characterized by at least two ductile Late Proterozoic deformation events (D1 and D2) followed by a brittle neotectonic deformation (D3). The early D1 event produced a regionally extensive S1 foliation, stretching/flattening mineral lineation L1 and symmetrical structural fabrics such as recumbent and isoclinal intra-folial folds (F1), implying a flattening deformation. D1 deformational fabrics are locally overprinted by D2 structures. D2 is characterized by a penetrative S2 foliation, shallow south plunging L2 lineation, asymmetric and sheath folds (F2) consistent with a right lateral sense of movement exhibited by delta- and sigma-type porphyroclast systems and asymmetric boudinage fabrics. D2 represents a non-coaxial flow regime formed in a dextral west over east shear zone during a partitioned transpression in response to east-west-directed compression during the assembly of Gondwana. A close resemblance with the Achankovil shear zone in India is noticed; however the continuation of the ASZ in Africa is uncertain.

Raharimahefa, Tsilavo; Kusky, Timothy M.; Toraman, Erkan; Rasoazanamparany, Christine; Rasaonina, Imboarina

2013-04-01

319

Post-collisional magmatism in the central East African Orogen: The Maevarano Suite of north Madagascar  

USGS Publications Warehouse

Late tectonic, post-collisional granite suites are a feature of many parts of the Late Neoproterozoic to Cambrian East African Orogen (EAO), where they are generally attributed to late extensional collapse of the orogen, accompanied by high heat flow and asthenospheric uprise. The Maevarano Suite comprises voluminous plutons which were emplaced in some of the tectonostratigraphic terranes of northern Madagascar, in the central part of the EAO, following collision and assembly during a major orogeny at ca. 550 Ma. The suite comprises three main magmatic phases: a minor early phase of foliated gabbros, quartz diorites, and granodiorites; a main phase of large batholiths of porphyritic granitoids and charnockites; and a late phase of small-scale plutons and sheets of monzonite, syenite, leucogranite and microgranite. The main phase intrusions tend to be massive, but with variably foliated margins. New U-Pb SHRIMP zircon data show that the whole suite was emplaced between ca. 537 and 522 Ma. Geochemically, all the rocks of the suite are enriched in the LILE, especially K, and the LREE, but are relatively depleted in Nb, Ta and the HREE. These characteristics are typical of post-collisional granitoids in the EAO and many other orogenic belts. It is proposed that the Maevarano Suite magmas were derived by melting of sub-continental lithospheric mantle that had been enriched in the LILE during earlier subduction events. The melting occurred during lithospheric delamination, which was associated with extensional collapse of the East African Orogen. ?? 2009 Natural Environment Research Council.

Goodenough, K.M.; Thomas, R.J.; De Waele, B.; Key, R.M.; Schofield, D.I.; Bauer, W.; Tucker, R.D.; Rafahatelo, J.-M.; Rabarimanana, M.; Ralison, A.V.; Randriamananjara, T.

2010-01-01

320

High resolution regional soil carbon mapping in Madagascar : towards easy to update maps  

NASA Astrophysics Data System (ADS)

The soil organic carbon plays an important role in climate change regulation through carbon emissions and sequestration due to land use changes, notably tropical deforestation. Monitoring soil carbon emissions from shifting-cultivation requires to evaluate the amount of carbon stored at plot scale with a sufficient level of accuracy to be able to detect changes. The objective of this work was to map soil carbon stocks (30 cm and 100 cm depths) for different land use at regional scale using high resolution satellite dataset. The Andohahela National Parc and its surroundings (South-Est Madagascar) - a region with the largest deforestation rate in the country - was selected as a pilot area for the development of the methodology. A three steps approach was set up: (i) carbon inventory using mid infra-red spectroscopy and stock calculation, (ii) spatial data processing and (iii) modeling and mapping. Soil spectroscopy was successfully used for measuring organic carbon in this region. The results show that Random Forest was the inference model that produced the best estimates on calibration and validation datasets. By using a simple and robust method, we estimated uncertainty levels of of 35% and 43% for 30-cm and 100-cm carbon maps respectively. The approach developed in this study was based on open data and open source software that can be easily replicated to other regions and for other time periods using updated satellite images.

Grinand, Clovis; Dessay, Nadine; Razafimbelo, Tantely; Razakamanarivo, Herintsitoaina; Albrecht, Alain; Vaudry, Romuald; Tiberghien, Matthieu; Rasamoelina, Maminiaina; Bernoux, Martial

2013-04-01

321

Extreme vulnerability of smallholder farmers to agricultural risks and climate change in Madagascar.  

PubMed

Across the tropics, smallholder farmers already face numerous risks to agricultural production. Climate change is expected to disproportionately affect smallholder farmers and make their livelihoods even more precarious; however, there is limited information on their overall vulnerability and adaptation needs. We conducted surveys of 600 households in Madagascar to characterize the vulnerability of smallholder farmers, identify how farmers cope with risks and explore what strategies are needed to help them adapt to climate change. Malagasy farmers are particularly vulnerable to any shocks to their agricultural system owing to their high dependence on agriculture for their livelihoods, chronic food insecurity, physical isolation and lack of access to formal safety nets. Farmers are frequently exposed to pest and disease outbreaks and extreme weather events (particularly cyclones), which cause significant crop and income losses and exacerbate food insecurity. Although farmers use a variety of risk-coping strategies, these are insufficient to prevent them from remaining food insecure. Few farmers have adjusted their farming strategies in response to climate change, owing to limited resources and capacity. Urgent technical, financial and institutional support is needed to improve the agricultural production and food security of Malagasy farmers and make their livelihoods resilient to climate change. PMID:24535397

Harvey, Celia A; Rakotobe, Zo Lalaina; Rao, Nalini S; Dave, Radhika; Razafimahatratra, Hery; Rabarijohn, Rivo Hasinandrianina; Rajaofara, Haingo; Mackinnon, James L

2014-04-01

322

Extreme vulnerability of smallholder farmers to agricultural risks and climate change in Madagascar  

PubMed Central

Across the tropics, smallholder farmers already face numerous risks to agricultural production. Climate change is expected to disproportionately affect smallholder farmers and make their livelihoods even more precarious; however, there is limited information on their overall vulnerability and adaptation needs. We conducted surveys of 600 households in Madagascar to characterize the vulnerability of smallholder farmers, identify how farmers cope with risks and explore what strategies are needed to help them adapt to climate change. Malagasy farmers are particularly vulnerable to any shocks to their agricultural system owing to their high dependence on agriculture for their livelihoods, chronic food insecurity, physical isolation and lack of access to formal safety nets. Farmers are frequently exposed to pest and disease outbreaks and extreme weather events (particularly cyclones), which cause significant crop and income losses and exacerbate food insecurity. Although farmers use a variety of risk-coping strategies, these are insufficient to prevent them from remaining food insecure. Few farmers have adjusted their farming strategies in response to climate change, owing to limited resources and capacity. Urgent technical, financial and institutional support is needed to improve the agricultural production and food security of Malagasy farmers and make their livelihoods resilient to climate change. PMID:24535397

Harvey, Celia A.; Rakotobe, Zo Lalaina; Rao, Nalini S.; Dave, Radhika; Razafimahatratra, Hery; Rabarijohn, Rivo Hasinandrianina; Rajaofara, Haingo; MacKinnon, James L.

2014-01-01

323

Multi-gene phylogeny of Madagascar's plated lizards, Zonosaurus and Tracheloptychus (Squamata: Gerrhosauridae).  

PubMed

We analyzed the phylogenetic relationships of the Malagasy plated lizards in the family Gerrhosauridae based on DNA sequence fragments of four mitochondrial and five nuclear genes. Various clades were strongly supported by the concatenated data set and also recovered by separate analyses of mtDNA and nucDNA. In particular, two clades here named the Z. rufipes group (containing Z. bemaraha , Z. brygooi , Z. rufipes , Z. subunicolor , Z. tsingy and an undescribed candidate species from northern Madagascar) and the Z. ornatus group (containing Z. anelanelany , Z. laticaudatus , Z. karsteni , Z. ornatus , Z. quadrilineaus, and Z. trilineatus) were resolved with strong support. A third clade named the Z. madagascariensis group contains Z. madagascariensis with a nested Z. haraldmeieri; the status of that species requires further investigation. Tentatively we also include Z. aeneus in this species group although its phylogenetic relationships were poorly resolved. A fourth clade with less support included Z. boettgeri and Z. maximus. The phylogenetic position of the genus Tracheloptychus remains uncertain: whereas in the species tree it was recovered as the sister group to Zonosaurus, other methods indicated that it was nested within Zonosaurus, albeit alternative topologies were rejected with only marginal statistical support. PMID:23831454

Recknagel, Hans; Elmer, Kathryn R; Noonan, Brice P; Raselimanana, Achille P; Meyer, Axel; Vences, Miguel

2013-12-01

324

Temporal patterns in a fish assemblage of a semiarid mangrove zone in Madagascar  

PubMed

Gillnet sampling was conducted for a year in a tropical mangrove creek (SW Madagascar), characterized by a limited freshwater influence, a high turbidity and a tidal range up to 3 m. Sixty species of juvenile fishes were caught, 44 species being of commercial interest. Catches were dominated by Gerreidae (27% of total abundance), Teraponidae (16%), Carangidae (13%) and Sparidae (12%). The temporary resident fishes in the mangrove zone represented 50% of the species and 97% of the total abundance, the other species being rare (less than five individuals). The species richness, abundance and biomass per netting were low in the middle of the cool season (July-August). Monthly changes in the fish assemblage were particularly complex, with three species groups displaying a clear seasonal pattern, some species succeeding one another in a rather unstructured way, and three species abundant throughout the year. There was no clear structuring effect of temperature, salinity and turbidity on the fish assemblage. However, tidal, lunar and diel effects on the composition of the fish assemblage were evident. The species overlap between the Sarodrano mangrove fauna and the adjacent coral reef fauna is particularly weak with six species in common and shows that the mangrove plays only a very limited nursery role for coral reef species. PMID:9236084

Laroche; Baran; Rasoanandrasana

1997-07-01

325

Treatment of an amelanotic melanoma using radiation therapy in a lesser Madagascar hedgehog tenrec (Echinops telfairi).  

PubMed

A 15-yr-old, male lesser Madagascar hedgehog tenrec (Echinops telfairi) presented with a mass caudal to the right ear. Cytology suggested a sarcoma. Surgical removal was attempted. Histology was consistent with a soft tissue sarcoma. The mass recurred within 331 days post operation. Radiation therapy was initiated. Computed tomography was used for staging in conjunction with three-dimensional computerized treatment planning software to permit accurate lesion localization and to optimize normal tissue sparing. A total dose of 6,480 cGy was administered in 24 fractions over 46 days. Transient hind limb paresis developed during the course of the radiation therapy, but resolved after 7 days with prednisone treatment. Minimal acute radiation toxicity was observed. The mass responded with at least a 90% reduction in volume following radiation treatment. The animal survived 266 days from the initiation of treatment. On necropsy, a small mass and granulation tissue were found at the site of the initial neoplasm, indicating good regional control of the tumor; however, extensive metastases to the spleen and liver were present. Immunohistochemically, the original, recurrent, and metastatic populations were strongly positive for HMB 45 and weakly positive for S-100, and the final diagnosis was metastatic amelanotic melanoma. PMID:20722271

Harrison, Tara M; Dominguez, Pedro; Hanzlik, Kim; Sikarskie, James G; Agnew, Dalen; Bergin, Ingrid; Fitzgerald, Scott D; Kitchell, Barbara E; McNiel, Elizabeth

2010-03-01

326

Seroprevalence of Antibodies against Chikungunya, Dengue, and Rift Valley Fever Viruses after Febrile Illness Outbreak, Madagascar  

PubMed Central

In October 2009, two3 months after an outbreak of a febrile disease with joint pain on the eastern coast of Madagascar, we assessed serologic markers for chikungunya virus (CHIKV), dengue virus (DENV), and Rift Valley fever virus (RVFV) in 1,244 pregnant women at 6 locations. In 2 eastern coast towns, IgG seroprevalence against CHIKV was 45% and 23%; IgM seroprevalence was 28% and 5%. IgG seroprevalence against DENV was 17% and 11%. No anti-DENV IgM was detected. At 4 locations, 4501,300 m high, IgG seroprevalence against CHIKV was 0%3%, suggesting CHIKV had not spread to higher inland-altitudes. Four women had IgG against RVFV, probably antibodies from a 2008 epidemic. Most (78%) women from coastal locations with CHIKV-specific IgG reported joint pain and stiffness; 21% reported no symptoms. CHIKV infection was significantly associated with high bodyweight. The outbreak was an isolated CHIKV epidemic without relevant DENV co-transmission. PMID:23092548

Girmann, Mirko; Randriamampionona, Njary; Bialonski, Alexandra; Maus, Deborah; Krefis, Anne Caroline; Njarasoa, Christine; Rajanalison, Jeanne Fleury; Ramandrisoa, Herly Daniel; Randriarison, Maurice Lucien; May, Jrgen; Schmidt-Chanasit, Jonas; Rakotozandrindrainy, Raphael

2012-01-01

327

Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar  

PubMed Central

Madagascar is one of the worlds top twelve megadiversity hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899) filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar. PMID:25224723

Maia, Joo P.; Crottini, Angelica; Harris, David James

2014-01-01

328

Kinematic evolution of the Morondava rift basin of SW Madagascar--from wrench tectonics to normal extension  

NASA Astrophysics Data System (ADS)

The evolution of the Karoo Basin system in SW Madagascar (Morondava Basin) may be considered to be an initial break-up attempt between East- and West-Gondwana in East Africa. The early rift evolution in the Morondava extensional basin in Madagascar was previously described in terms of orthogonal crustal extension with either E-W or NW-SE directed extensional strain. Detailed field investigations in three areas of the Morondava Basin, subsequent to LANDSAT TM 5 and SPOT 4 satellite image interpretations, revealed, that crustal extension in the Morondava Basin and associated sedimentation of the Karoo Supergroup sequences occurred in three different periods under three different stress and kinematic regimes (referred to the actual position of Madagascar): Sinistral strike-slip movement (Early-?Late Permian), post-dating lower Sakoa Group deposition, and syn-depositional with middle Sakoa Group sedimentation. Formation of N-trending pull-apart basins. Sinistral strike-slip movement (post-latest Permian), post-dating lower Sakamena Group sediments and syn-depositional normal faulting (latest Permian). Formation of transtensional basins. NW-directed normal extension (Early-Middle Triassic) post-dating the middle Sakamena to lower Isalo Group I and pre-dating lower Isalo Group II deposition. Formation of half-grabens. Throughout the Permian period, strike-slip deformation, triggered by approximately N-S oriented compressive intraplate stresses, resulted in the formation of relatively limited pull-apart basins. At around the Permian-Triassic transition, the stress system gradually developed towards transtension with the consequence of significant widening of the depositional system. From the Early Triassic onwards, the stress system was purely tensional with widespread normal faulting prevailing, resulting in the increasing formation of half-graben systems, characterised by orthogonal extensional strain.

Schandelmeier, H.; Bremer, F.; Holl, H.-G.

2004-03-01

329

Extinction vulnerability of tropical montane endemism from warming and upslope displacement: a preliminary appraisal for the highest massif in Madagascar  

PubMed Central

One of the predicted biological responses to climate warming is the upslope displacement of species distributions. In the tropics, because montane assemblages frequently include local endemics that are distributed close to summits, these species may be especially vulnerable to experiencing complete habitat loss from warming. However, there is currently a dearth of information available for tropical regions. Here, we present a preliminary appraisal of this extinction threat using the herpetological assemblage of the Tsaratanana Massif in northern Madagascar (the island's highest massif), which is rich with montane endemism. We present meteorological evidence (individual and combined regional weather station data and reanalysis forecast data) for recent warming in Madagascar, and show that this trend is consistent with recent climate model simulations. Using standard moist adiabatic lapse rates, these observed meteorological warming trends in northern Madagascar predict upslope species displacement of 1774 m per decade between 1993 and 2003. Over this same period, we also report preliminary data supporting a trend for upslope distribution movements, based on two surveys we completed at Tsaratanana. For 30 species, representing five families of reptiles and amphibians, we found overall mean shifts in elevational midpoint of 1951 m upslope (mean lower elevation limit 29114 m; mean upper elevation limit ?8 to 53 m). We also found upslope trends in mean and median elevational observations in seven and six of nine species analysed. Phenological differences between these surveys do not appear to be substantial, but these upslope shifts are consistent with the predictions based on meteorological warming. An elevational range displacement analysis projects complete habitat loss for three species below the 2 C dangerous warming threshold. One of these species is not contracting its distribution, but the other two were not resampled in 2003. A preliminary review of the other massifs in Madagascar indicates potential similar vulnerability to habitat loss and upslope extinction. Consequently, we urgently recommend additional elevational surveys for these and other tropical montane assemblages, which should also include, when possible, the monitoring of local meteorological conditions and habitat change.

RAXWORTHY, CHRISTOPHER J; PEARSON, RICHARD G; RABIBISOA, NIRHY; RAKOTONDRAZAFY, ANDRY M; RAMANAMANJATO, JEAN-BAPTISTE; RASELIMANANA, ACHILLE P; WU, SHENGHAI; NUSSBAUM, RONALD A; STONE, DITH A

2008-01-01

330

Biogeography of the two major arbovirus mosquito vectors, Aedes aegypti and Aedes albopictus (Diptera, Culicidae), in Madagascar  

PubMed Central

Background In the past ten years, the Indian Ocean region has been the theatre of severe epidemics of chikungunya and dengue. These outbreaks coincided with a high increase in populations of Aedes albopictus that outcompete its sister taxon Aedes aegypti in most islands sampled. The objective of this work was to update the entomological survey of the two Aedes species in the island of Madagascar which has to face these arboviroses. Methods The sampling of Aedes mosquitoes was conducted during two years, from October 2007 to October 2009, in fifteen localities from eight regions of contrasting climates. Captured adults were identified immediately whereas immature stages were bred until adult stage for determination. Phylogenetic analysis was performed using two mtDNA genes, COI and ND5 and trees were constructed by the maximum likelihood (ML) method with the gene time reversible (GTR) model. Experimental infections with the chikungunya virus strain 06.21 at a titer of 107.5 pfu/mL were performed to evaluate the vector competence of field-collected mosquitoes. Disseminated infection rates were measured fourteen days after infection by immunofluorescence assay performed on head squashes. Results The species Aedes aegypti was detected in only six sites in native forests and natural reserves. In contrast, the species Aedes albopictus was found in 13 out of the 15 sites sampled. Breeding sites were mostly found in man-made environments such as discarded containers, used tires, abandoned buckets, coconuts, and bamboo cuts. Linear regression models showed that the abundance of Ae. albopictus was significantly influenced by the sampling region (F = 62.00, p < 2.2 10-16) and period (F = 36.22, p = 2.548 10-13), that are associated with ecological and climate variations. Phylogenetic analysis of the invasive Ae. albopictus distinguished haplotypes from South Asia and South America from those of Madagascar, but the markers used were not discriminant enough to discern Malagasy populations. The experimental oral infection method showed that six Ae. albopictus populations exhibited high dissemination infection rates for chikungunya virus ranging from 98 to 100%. Conclusion In Madagascar, Ae. albopictus has extended its geographical distribution whereas, Ae. aegypti has become rare, contrasting with what was previously observed. Changes are predominantly driven by human activities and the rainfall regime that provide suitable breeding sites for the highly anthropophilic mosquito Ae. albopictus. Moreover, these populations were found to be highly susceptible to chikungunya virus. In the light of this study, Ae. albopictus may have been involved in the recent outbreaks of chikungunya and dengue epidemics in Madagascar, and consequently, control measures should be promoted to limit its current expansion. PMID:22433186

2012-01-01

331

Top soil radioactivity assessment in a high natural radiation background area: the case of Vinaninkarena, Antsirabe-Madagascar.  

PubMed

The village of Vinaninkarena, Antsirabe, Madagascar (47 degrees 02'40''E, 19 degrees 57'17''S) is located in a high natural radioactivity area. In order to evaluate the natural radionuclide content in soil, sampling was done on-site by the transect method (85 soil samples) and off-site through transects across and beyond the region (up to a range of 100 km), to determine the natural radioactivity variation within vs. outside the region, and to detect significant differences, taking into account spatial variability. PMID:18502647

Rabesiranana, Naivo; Rasolonirina, Martin; Terina, Franck; Solonjara, Asivelo F; Andriambololona, Raoelina

2008-11-01

332

Rainforest Pharmacopeia in Madagascar Provides High Value for Current Local and Prospective Global Uses  

PubMed Central

Botanical diversity provides value to humans through carbon sequestration, air and water purification, and the provisioning of wild foods and ethnomedicines. Here we calculate the value of botanical ethnomedicines in a rainforest region of Madagascar, the Makira Protected Area, using a substitution method that combines replacement costs and choice modeling. The Makira watershed may comprise approximately 0.8% of global botanical diversity and possesses enormous value both in its ability to provision botanical ethnomedicines to local people and as a source of potentially novel pharmaceutical drugs for society as a whole. Approximately 241 locally-recognized species are used as ethnomedicines, including 113 agricultural or weed species. We equated each ethnomedicinal treatment to the monetary value of a comparable pharmaceutical treatment adjusted by personal preferences in perceived efficacy (rather than from known or assumed medicinal equivalency). The benefit value of these botanical ethnomedicines per individual is $5.407.90 per year when using the value of highly subsidized Malagasy pharmaceuticals and $100.60287.40 when using the value of American pharmaceuticals. Using local pharmaceuticals as substitutes, the value per household is $30.2444.30 per year, equivalent to 4363% of median annual household income, demonstrating their local importance. Using the value of American pharmaceuticals, the amount is equivalent to 2263% of the median annual health care expenditures for American adults under 45 in 2006. The potential for developing novel biomedicines from the Makira watersheds unique flora ranges in untapped benefit value from $0.35.7 billion for American pharmaceutical companies, non-inclusive of the importance of providing novel medicines and improved healthcare to society. This study provides evidence of the tremendous current local and prospective global value of botanical ethnomedicines and furthers arguments for the conservation of tropical forests for sustainable use. Botanique de la diversit apporte de la valeur lhomme par la squestration du carbone, de lair et de purification de leau, et le provisionnement des aliments sauvages et ethnomedicines. Ici, nous calculons la valeur de ethnomedicines botaniques dans une rgion de fort de Madagascar, la zone protge de Makira, en utilisant une mthode de substitution qui combine les cots de remplacement et la modlisation des choix. Le bassin versant de Makira peut comprendre environ 0,8% de la diversit botanique mondiale et possde une valeur norme la fois dans sa capacit fournir ethnomedicines botaniques la population locale et en tant que source de nouveaux mdicaments potentiellement pharmaceutiques pour la socit dans son ensemble. Environ 241 espces localement reconnus sont utiliss comme ethnomedicines, y compris 113 espces dagricoles ou de mauvaises herbes. Nous assimil chaque traitement ethnomdicales la valeur montaire dun traitement comparable pharmaceutique ajust en fonction des prfrences personnelles en matire defficacit perue (plutt que de lquivalence mdicament connu ou suppos). La valeur de lavantage de ces ethnomedicines botaniques par individu est de $5,40 7.90 par anne lors de lutilisation de la valeur des produits pharmaceutiques malgaches fortement subventionns et de $100,60 287,40 lors de lutilisation de la valeur des produits pharmaceutiques amricains. Utilisation de produits pharmaceutiques locales comme des substituts, la valeur par mnage est de $30.24 44.30 par an, quivalent 4363% du revenu mdian des mnages annuelle, ce qui dmontre leur importance locale. Utilisation de la valeur des produits pharmaceutiques

Golden, Christopher D.; Rasolofoniaina, B. J. Rodolph; Anjaranirina, E. J. Gasta; Nicolas, Lilien; Ravaoliny, Laurent; Kremen, Claire

2012-01-01

333

Patterns of Loss and Regeneration of Tropical Dry Forest in Madagascar: The Social Institutional Context  

PubMed Central

Loss of tropical forests and changes in land-use/land-cover are of growing concern worldwide. Although knowledge exists about the institutional context in which tropical forest loss is embedded, little is known about the role of social institutions in influencing regeneration of tropical forests. In the present study we used Landsat images from southern Madagascar from three different years (1984, 1993 and 2000) and covering 5500 km2, and made a time-series analysis of three distinct large-scale patterns: 1) loss of forest cover, 2) increased forest cover, and 3) stable forest cover. Institutional characteristics underlying these three patterns were analyzed, testing the hypothesis that forest cover change is a function of strength and enforcement of local social institutions. The results showed a minor decrease of 7% total forest cover in the study area during the whole period 19842000, but an overall net increase of 4% during the period 19932000. The highest loss of forest cover occurred in a low human population density area with long distances to markets, while a stable forest cover occurred in the area with highest population density and good market access. Analyses of institutions revealed that loss of forest cover occurred mainly in areas characterized by insecure property rights, while areas with well-defined property rights showed either regenerating or stable forest cover. The results thus corroborate our hypothesis. The large-scale spontaneous regeneration dominated by native endemic species appears to be a result of a combination of changes in precipitation, migration and decreased human population and livestock grazing pressure, but under conditions of maintained and well-defined property rights. Our study emphasizes the large capacity of a semi-arid system to spontaneously regenerate, triggered by decreased pressures, but where existing social institutions mitigate other drivers of deforestation and alternative land-use. PMID:17476324

Elmqvist, Thomas; Pyyknen, Markku; Teng, Maria; Rakotondrasoa, Fanambinantsoa; Rabakonandrianina, Elisabeth; Radimilahy, Chantal

2007-01-01

334

Epidemiology of Pathogenic Enterobacteria in Humans, Livestock, and Peridomestic Rodents in Rural Madagascar  

PubMed Central

Background Among the families of enteric bacteria are globally important diarrheal agents. Despite their potential for zoonotic and environmental transmission, few studies have examined the epidemiology of these pathogens in rural systems characterized by extensive overlap among humans, domesticated and peridomestic animals. We investigated patterns of infection with Enterotoxigenic Escherichia coli, Shigella spp., Salmonella enterica, Vibrio cholerae, and Yersinia spp. (enterocolitica, and pseudotuberculosis) in Southeastern Madagascar where the potential for the aforementioned interactions is high. In this pilot project we conducted surveys to examine behaviors potentially associated with risk of infection and if infection with specific enterobacteria species was associated with diarrheal disease. Methodology/Principal Findings PCR was conducted on DNA from human, livestock, and rodent fecal samples from three villages. Overall, human prevalence was highest (77%), followed by rodents (51%) and livestock (18%). Rodents were ?2.8 times more likely than livestock to carry one of the bacteria. The incidence of individual species varied between villages, with the observation that, E. coli and Shigella spp. were consistently associated with co-infections. As an aggregate, there was a significant risk of infection linked to a water source in one village. Individually, different pathogens were associated with certain behaviors, including: those who had used medication, experienced diarrhea in the past four weeks, or do not use toilets. Conclusions/Significance Different bacteria were associated with an elevated risk of infection for various human activities or characteristics. Certain bacteria may also predispose people to co-infections. These data suggest that a high potential for transmission among these groups, either directly or via contaminated water sources. As these bacteria were most prevalent in humans, it is possible that they are maintained in humans and that transmission to other species is infrequent. Further studies are needed to understand bacterial persistence, transmission dynamics, and associated consequences in this and similar systems. PMID:24983990

Bublitz, DeAnna C.; Wright, Patricia C.; Bodager, Jonathan R.; Rasambainarivo, Fidisoa T.; Bliska, James B.; Gillespie, Thomas R.

2014-01-01

335

A 12-month survey of gastrointestinal helminth infections of lemurs kept in two zoos in Madagascar.  

PubMed

Infections with gastrointestinal parasites may be a major threat to lemurs kept in captivity, as they are a common cause of diarrhea. In this study, fecal egg count patterns and clinical signs associated with gastrointestinal nematodes were assessed for 12 mo in 40 lemurs kept under different husbandry and climatic conditions at two sites in Madagascar. Involved species were black-and-white ruffed lemurs (Varecia variegata), eastern grey bamboo lemurs (Hapalemur griseus), greater bamboo lemurs (Prolemur simus), red-bellied lemurs (Eulemur rubriventer), common brown lemurs (Eulemurfulvus), crowned lemurs (Eulemur coronatus), and Sclater's black lemurs (Eulemur macaco flavifrons). At site 1 (Tsimbazaza Zoological Park), lemurs were kept in small enclosures with daily cleaning of the cement soiling and without routine anthelmintic program, whereas at site 2 (Ivoloina Zoological Park), lemurs received routine anthelmintic prophylaxis and were housed in small enclosure with daily cleaning of sandy soil enclosures. A total of five genera of nematode eggs from the orders Strongylida, Oxyurida, and Enoplida were recovered and identified from 198 out of 240 samples (83%) at site 1 and 79% (189 out of 240) at site 2 with the use of a modified McMaster technique. Significant differences were found for parasites from the order Strongylida between the two sites. The differences may be due to climate conditions and the presumed life cycle of these parasites. No significant differences were found for parasites from the other orders. No significant differences were noted between sexes or between seasons. No clinical signs of parasitic gastroenteritis were seen in either lemur collection. PMID:21370644

Rasambainarivo, Fidisoa T; Junge, Randall E

2010-12-01

336

Physical influence on biological production along the western shelf of Madagascar  

NASA Astrophysics Data System (ADS)

In September 2009, the R.V. Dr. Fridtjof Nansen surveyed the western coast of Madagascar. Environmental parameters of temperature, salinity, fluorescence and oxygen were profiled with a CTD probe and continuously underway at 5 m utilising a thermosalinograph equipped with a fluorescence sensor. A ship mounted Acoustic Doppler Current Profiler (ADCP) provided current profiles down to 250 m, while estimates of biomass were obtained from acoustics and trawling was used for species identification. In addition, visual whale observations were conducted. The survey revealed three areas that were identified as upwelling regions, namely the Southern Coast (26S), offshore from Cap St. Andr (16S) and near Nosy Be Island (13S). In these upwelling regions, acoustic estimates, trawling and whale observations indicated high biological productivity. The total acoustic estimate for the whole western coast was as low as 62 000 t, typical for tropical waters. In addition to the upwelling areas, high biological productivity was also found outside river mouths. Ship born wind measurements, as well as re-analysed wind fields, indicated that the southern coast upwelling cell was wind-driven and had a larger extent than reported earlier. The wind conditions were not favourable for upwelling in the two northernmost upwelling cells. Here the ADCP showed high bottom velocities (>1 m s-1) oriented northeast. These currents were probably forced by the migrating eddies in the area as indicated by the remotely sensed Sea Level Anomaly (SLA). Such currents induce bottom friction layer transport oriented towards the coast, thus driving upwelling, although not necessarily penetrating all the way to the surface layer as was the case near Cap St. Andr.

Pripp, T.; Gammelsrd, T.; Krakstad, J. O.

2014-02-01

337

Phase equilibrium modeling of Pan-African incipient charnockite from southern Madagascar  

NASA Astrophysics Data System (ADS)

Dark brownish patches and/or veins of coarse-grained orthopyroxene-bearing felsic granulite (charnockite) within foliated amphibolite-facies gneiss/migmatite, are considered as examples of 'metamorphic' charnockite, and represent the transformation of amphibolite-facies rocks to dry granulites on a local scale. Such 'incipient' charnockites have been reported so far from many localities in southern India and Sri Lanka which corresponds to the central part of the East African - Antarctic Orogenic Belt related to the assembly of the Gondwana Supercontinent. Detailed petrological investigations of incipient charnockites therefore provide important insights into granulite-forming processes in the lower crust during Neoproterozoic to Cambrian. Here, we report the first occurrence of incipient charnockite from Ihosy area in southern Madagascar, and discuss the petrogenesis of granulite formation in an arrested stage on the basis of petrography, geothermobarometry, fluid inclusion study, and mineral equilibrium modeling. In the study area, patches of brownish charnockite (Pl+ Qtz + Kfs + Bt + Grt + Opx + Ilm + Mag) of about 20 to 50 cm in length occur within host orthopyroxene-free garnet-biotite gneiss (Pl + Qtz + Kfs + Bt + Grt + Ilm + Mag). The application of mineral equilibrium modeling on charnockite assemblage in NCKFMASHTO system to constrain the conditions of charnockitization defines a P - T range of 8-10.5 kbar and 820-880 C, which is broadly consistent with the results from the conventional geothermobarometry (820-880 C at 9 kbar) on Grt-Bt gneiss. The result of T versus mole H2O (M(H2O)) modeling demonstrated that orthopyroxene-free assemblage in Grt-Bt gneiss is stable only at M(H2O) >0.1 mol.%, while orthopyroxene in charnockite occurs as a stable mineral at very low M(H2O) condition of

Tsunogae, Toshiaki; Endo, Takahiro; Santosh, Mw; Thierry Rakotonandrasana, N. O.; Shaji, Erath; Rambeloson, Roger A.

2013-04-01

338

Phylogenomics and taxonomy of Lecomtelleae (Poaceae), an isolated panicoid lineage from Madagascar  

PubMed Central

Background and Aims An accurate characterization of biodiversity requires analyses of DNA sequences in addition to classical morphological descriptions. New methods based on high-throughput sequencing may allow investigation of specimens with a large set of genetic markers to infer their evolutionary history. In the grass family, the phylogenetic position of the monotypic genus Lecomtella, a rare bamboo-like endemic from Madagascar, has never been appropriately evaluated. Until now its taxonomic treatment has remained controversial, indicating the need for re-evaluation based on a combination of molecular and morphological data. Methods The phylogenetic position of Lecomtella in Poaceae was evaluated based on sequences from the nuclear and plastid genomes generated by next-generation sequencing (NGS). In addition, a detailed morphological description of L. madagascariensis was produced, and its distribution and habit were investigated in order to assess its conservation status. Key Results The complete plastid sequence, a ribosomal DNA unit and fragments of low-copy nuclear genes (phyB and ppc) were obtained. All phylogenetic analyses place Lecomtella as an isolated member of the core panicoids, which last shared a common ancestor with other species >20 million years ago. Although Lecomtella exhibits morphological characters typical of Panicoideae, an unusual combination of traits supports its treatment as a separate group. Conclusions The study showed that NGS can be used to generate abundant phylogenetic information rapidly, opening new avenues for grass phylogenetics. These data clearly showed that Lecomtella forms an isolated lineage, which, in combination with its morphological peculiarities, justifies its treatment as a separate tribe: Lecomtelleae. New descriptions of the tribe, genus and species are presented with a typification, a distribution map and an IUCN conservation assessment. PMID:23985988

Besnard, Guillaume; Christin, Pascal-Antoine; Mal, Pierre-Jean G.; Coissac, Eric; Ralimanana, Hlne; Vorontsova, Maria S.

2013-01-01

339

Renaud Paulian et le programme du CNRS sur les hautes montagnes Madagascar: tage vs domaine  

PubMed Central

Rsum Le programme intitul tude des cosystmes montagnards dans la rgion malgache (RCP 225/CNRS; responsable: Recteur Renaud Paulian) avait pour ambition de dgager leurs caractres gnraux, l'origine des lments constitutifs et de tester la validit d'un Domaine malgache des Hautes Montagnes propos par Humbert ds 1951. De 1970 1973, trois campagnes (Andringitra; Chanes anosyennes et Ankaratra; Itremo, Ibity et Marojejy) ont permis une caractrisation cologique des milieux particuliers ainsi que des analyses de systmatique sur certains taxa connus pour leur intrt biogographique. La succession altitudinale des formations vgtales, dfinies par des critres physionomiques et structuraux, est prcise par massif. Le dernier tage caractris par le fourr ricode et ses groupements associs ne correspond pas l'tage des Hautes Montagnes de l'Est africain. Des groupes de la faune (invertbrs hexapodes: Collemboles et Dermaptres) indiquent une disjonction entre les massifs du Nord (Tsaratanana, Marojejy), ceux du Centre et du Sud; des lments de la flore (Pandanaceae, Araliaceae, Asteraceae) sont en cours d'analyse dans le mme sens. Le Domaine des Hautes montagnes Madagascar est une ralit cologique mais ne peut tre dfini floristiquement; chaque massif montagneux est une entit phytogographique d'tages de vgtation interdpendants inclus dans les diffrents Sous-Domaines du Centre. Les groupes peu mobiles de la faune indiquent globalement une dpendance trophique et bioclimatique (effet tampon du climat intraforestier) vis--vis des tages de vgtation, mais peuvent ragir des microclimats locaux par des dcalages leurs limites. PMID:21731422

Guillaumet, Jean-Louis; Betsch, Jean-Marie; Callmander, Martin W.

2011-01-01

340

Semi-quantitative tests of cyanide in foods and excreta of Three Hapalemur species in Madagascar.  

PubMed

Three sympatric Hapalemur species (H. g. griseus, H. aureus, and H. (Prolemur) simus) in Ranomafana National Park, Madagascar are known to eat bamboo food parts that contain cyanide. How these lemurs avoid cyanide poisoning remains unknown. In this study, we tested for the presence/absence of cyanide in bamboo lemur foods and excreta to (1) document patterns of cyanide consumption among species with respect to diet, (2) identify routes of elimination of cyanide from the gastrointestinal tract, and (3) determine whether cyanide is absorbed from the diet. We tested 102 food, urine, and fecal samples for hydrogen cyanide (HCN) during two "pre-dry" seasons (April 2006, May 2007) using commercially available Cyantesmo test strips. The test strips changed color in the presence of HCN, and we recorded color change on a scale of 0 (no change) to 5 (cobalt) at preset intervals with a final score taken at 24 hr. We detected cyanide in bamboo food parts and urine of all three Hapalemur species. Time to color change of the test strips ranged from almost instantaneous to >12 hr incubation. Of the foods tested, only bamboo contained cyanide, but results differed among bamboo species and plant parts of the same species. Specifically, branch shoot and culm pith of the giant bamboo produced strong, immediate reactions to the test paper, whereas parts of liana bamboos produced either weak or no color change. Cyanide was present in almost all urine samples but rarely in fecal samples. This suggests that dietary cyanide is absorbed in the gastrointestinal tract of the Hapalemur species and excreted, at least in part, by the kidneys. Samples from H. griseus exhibited lower, though still detectable, cyanide levels compared with H. simus and H. aureus. Differences among lemur species appear to be related to the specific bamboo parts consumed. PMID:19790190

Yamashita, Nayuta; Tan, Chia L; Vinyard, Christopher J; Williams, Cathy

2010-01-01

341

Petrology of ultramafic xenoliths in Cenozoic alkaline rocks of northern Madagascar (Nosy Be Archipelago)  

NASA Astrophysics Data System (ADS)

Late Miocene basanites of Nosy Be and Nosy Sakatia islands (Nosy Be Archipelago, northern Madagascar) carry spinel-facies anhydrous ultramafic xenoliths (lherzolites, harzburgites and wehrlites). Geothermobarometric estimates indicate that these xenoliths derive from shallow mantle depths of 35-40 km, with those from Nosy Be island showing equilibration T (averages in the range of 945-985 C) lower than the Nosy Sakatia analogues (averages ranging from 1010 to 1110 C). One Nosy Sakatia mantle xenolith exhibits relatively fertile lherzolite composition, with trace and major element mineral chemistry consistent with a residual character after low degrees (1-2%) of mafic melt extraction. We interpret this composition as that resembling a depleted mantle (DM)-like lithospheric composition before metasomatic overprints. The other lherzolites and harzburgites display petrochemical characters consistent with variable extent of partial melting (up to 18%), associated with pronounced metasomatic overprints caused by migrating melts, as highlighted by enrichments in highly incompatible trace elements (e.g. light rare earth elements, LREE and Sr), together with the abundant occurrence of wehrlitic lithologies. The variability of petrochemical features points to different styles of metasomatism and metasomatic agents. The estimated composition of the parental melts of wehrlites matches that of host basanites. The combination of this evidence with the petrographic features, characterized by coarse-granular to porphyroclastic textures and by the presence of olivine without kink-banding, suggests that wehrlites are veins or pockets of high pressure cumulates within the mantle peridotite. The same melts also metasomatized via porous-flow percolation some lherzolites and harzburgites. Distinctly, a group of lherzolites and harzburgites was metasomatized by a different alkaline melt having markedly lower incompatible trace element contents. Late infiltration of metasomatic fluids is responsible for the spongy texture of some clinopyroxenes of lherzolites, harzburgites and wehrlites.

Rocco, Ivana; Lustrino, Michele; Zanetti, Alberto; Morra, Vincenzo; Melluso, Leone

2013-01-01

342

The importance of taboos and social norms to conservation in Madagascar.  

PubMed

Informal institutions governing the use of wild species are present in many societies. A system of prohibitions known as fady is central to Malagasy culture. We examined whether fady that relate to the use of natural resources in the eastern rainforests of Madagascar play an important conservation role. Prohibitions ranged from strict taboos in which a species or area was forbidden by the ancestors to social norms that concerned acceptable behavior when harvesting wild species. Strict taboos offered real protection to threatened species, such as the lemur Propithecus edwardsi and the carnivore Cryptoprocta ferox. Taboos also reduced pressure on some economically important endemic species by preventing their sale or limiting the harvest season. Despite their value for conservation, the taboos did not appear to originate from attempts to sustainably manage resources. Nevertheless, social norms, in which the sanction was social disapproval rather than supernatural retribution, encouraged sustainable harvesting practices for tenrecs (Tenrec ecudatus) and pandans (Pandanus spp.). Unfortunately, the social norms concerning methods of harvesting pandans appeared to be breaking down in villages surrounding Ranomafana National Park, and we suggest that the imposition of external conservation rules is weakening traditional management. Informal institutions are important to conservation because they suggest ways of improving cultural understanding and conservation communication. Food taboos influence societal preferences, which affect the wider demand for a species. Most important, where capacity to enforce external conservation rules is limited, informal institutions may provide the only effective regulations. Informal institutions should receive greater attention from conservation biologists so that local people's conservation roles can be acknowledged fairly and so that potential synergies with conservation objectives can be realized. PMID:18616743

Jones, Julia P G; Andriamarovololona, Mijasoa M; Hockley, Neal

2008-08-01

343

Molecular evidence for the monophyly of tenrecidae (mammalia) and the timing of the colonization of Madagascar by Malagasy Tenrecs.  

PubMed

Tenrecs are a diverse family of insectivores, with an Afro-Malagasian biogeographic distribution. Three subfamilies (Geogalinae, Oryzorictinae, Tenrecinae) are restricted to Madagascar and one subfamily, the otter shrews (Potamogalinae), occurs on the mainland. Morphological studies have generated conflicting hypotheses according to which both tenrecids and Malagassy tenrecs are either monophyletic or paraphyletic. Competing hypotheses have different implications for the biogeographic history of Tenrecidae. At present, there are no molecular studies that address these hypotheses. The present study provides sequences of a nuclear protein-coding gene (vWF) and the mitochondrial 12S rRNA, tRNA valine, and 16S rRNA genes from a potamogaline (Micropotamogale). New sequences of these genes are also reported for the tenrecine, Tenrec ecaudatus. The 12S sequences from these taxa were combined with data already available for this locus from two other tenrecids (Echinops telfairi, subfamily Tenrecinae and Oryzorictes talpoides, subfamily Oryzorictinae). Phylogenetic analyses provided strong bootstrap support for the monophyly of Tenrecidae and Malagasy tenrecs. The majority of statistical tests rejected morphological claims for both a Tenrecinae--Chrysochloridae clade and an Oryzorictinae--Potamogalinae clade. Molecular clock estimates suggest a split of otter shrews and Malagasy tenrecs at approximately 53 MYA. We estimate that the ancestor of Malagasy tenrecs dispersed to Madagascar subsequent to this split but prior to about 37 MYA. PMID:11884160

Douady, Christophe J; Catzeflis, Francois; Kao, Diana J; Springer, Mark S; Stanhope, Michael J

2002-03-01

344

The Arabo-Islamic migrations in Madagascar: first genetic study of the GM system in three Malagasy populations.  

PubMed

The Antemoro are an ethnic group from the southeast coast of Madagascar who claims an Arab origin. Cultural signatures of an Arabo-Islamic influence have been found in this region. Nevertheless, their origins are very contentious. Through this study, we want to determine whether this ethnic group had a particular GM profile that differentiated it from other Malagasy populations, and whether there were detectable genetic traces of the Arabo-Islamic migration. The Gm polymorphisms of IgG immunoglobulins was analysed in a population of Antemoro (N = 85), two other Malagasy populations from northern Fihere?a (N = 82) and southern Fihere?a (N = 50) and in a Comorian population (N = 171). This last group was used to enlarge the database for genetic comparisons. Results revealed significant contributions from Africa (60%, 0.092 ?F(ST) ? 0.280) and Southeast Asia (40%, 0.043 ? F(ST) ? 0.590) to the Antemoro genetic pool. No direct genetic relationships with the Middle East. These results bring new insights into the population history of Madagascar. PMID:22168175

Capredon, M; Sanchez-Mazas, A; Guitard, E; Razafindrazaka, H; Chiaroni, J; Champion, B; Dugoujon, J-M

2012-04-01

345

Genome-wide evidence of AustronesianBantu admixture and cultural reversion in a hunter-gatherer group of Madagascar  

PubMed Central

Linguistic and cultural evidence suggest that Madagascar was the final point of two major dispersals of Austronesian- and Bantu-speaking populations. Today, the Mikea are described as the last-known Malagasy population reported to be still practicing a hunter-gatherer lifestyle. It is unclear, however, whether the Mikea descend from a remnant population that existed before the arrival of Austronesian and Bantu agriculturalists or whether it is only their lifestyle that separates them from the other contemporary populations of South Madagascar. To address these questions we have performed a genome-wide analysis of >700,000 SNP markers on 21 Mikea, 24 Vezo, and 24 Temoro individuals, together with 50 individuals from Bajo and Lebbo populations from Indonesia. Our analyses of these data in the context of data available from other Southeast Asian and African populations reveal that all three Malagasy populations are derived from the same admixture event involving Austronesian and Bantu sources. In contrast to the fact that most of the vocabulary of the Malagasy speakers is derived from the Barito group of the Austronesian language family, we observe that only one-third of their genetic ancestry is related to the populations of the Java-Kalimantan-Sulawesi area. Because no additional ancestry components distinctive for the Mikea were found, it is likely that they have adopted their hunter-gatherer way of life through cultural reversion, and selection signals suggest a genetic adaptation to their new lifestyle. PMID:24395773

Pierron, Denis; Razafindrazaka, Harilanto; Pagani, Luca; Ricaut, Franois-Xavier; Antao, Tiago; Capredon, Mlanie; Sambo, Clment; Radimilahy, Chantal; Rakotoarisoa, Jean-Aim; Blench, Roger M.; Letellier, Thierry; Kivisild, Toomas

2014-01-01

346

First description of autumn migration of Sooty Falcon Falco concolor from the United Arab Emirates to Madagascar using satellite telemetry  

USGS Publications Warehouse

The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon's autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

Javed, Salim; Douglas, David C.; Khan, Shahid Noor; Nazeer Shah, Junid; Ali Al Hammadi, Abdullah

2012-01-01

347

Look at That!: Using Madagascar Hissing Cockroaches to Develop and Enhance the Scientific Inquiry Skill of Observation in Middle School Students  

ERIC Educational Resources Information Center

Middle school students can develop and enhance their observation skills by participating in teacher-guided scientific inquiry (NRC 1996) activities where they observe animals that tend to act in known, predictable ways. Madagascar hissing cockroaches ("Gromphadorhina portentosa") are one such animal. This article presents beginning, intermediate,

Wagler, Ron

2011-01-01

348

Similarities, differences, and seasonal patterns in the diets of Eulemur rubriventer and Eulemur fulvus rufus in the Ranomafana National Park, Madagascar  

Microsoft Academic Search

I studied the diets of two sympatric species ofEulemur (E. fulvus rufus andE. rubriventer) in the Ranomafana National Part in southeastern Madagascar from July 1988 through August 1989. Both species were highly frugivorous throughout the year and devoted similar amounts of time to feeding daily; the composition of their diets were similar. Three aspects of both lemur species' diets were

Deborah J. Overdorff

1993-01-01

349

"Even with Higher Education You Remain a Woman": A Gender Perspective on Higher Education and Social Change in the Toliara Region of Madagascar  

ERIC Educational Resources Information Center

This article investigates some issues related to gender and education based on a qualitative, empirical study of women in higher education in the Toliara region of Madagascar. The focus is on how women's participation in higher education has created changes in gender relations, and how these women have succeeded in achieving higher education. In

Skjortnes, Marianne; Zachariassen, Heidi Holt

2010-01-01

350

The skull and pectoral girdle of the parasemionotid fish Watsonulus eugnathoides from the Early Triassic Sakamena Group of Madagascar, with comments on the relationships of the holostean fishes  

Microsoft Academic Search

Watsonulus eugnathoides (Piveteau, 1935) is a parasemionotid fish from Early Triassic rocks of Madagascar. The skull and pectoral girdle of this holostean are described from new material. The braincase retains a number of primitive chondrostean-like characters such as an open lateral cranial fissure and frequently open vestibular fontanelle, presence of an endochondral intercalar without membranous outgrowths, and fusion between most

Paul Eric Olsen

1984-01-01

351

Developpement, amenagement linguistique et terminologie: Un mythe? L'exemple de la malgachisation (Development, Language Planning, and Terminology: A Myth? The Example of Madagascar).  

ERIC Educational Resources Information Center

The French language provides a context for comparison of the modernization efforts of Quebec and Madagascar, looking at the following issues: the beginning role of the language in the society, political influences, language needs for technology transfer and the introduction of terminology in societies with well-documented and poorly-documented

Boulanger, Jean-Claude

1989-01-01

352

A TAXONOMIC REVISION OF GOUANIA (RHAMNACEAE) IN MADAGASCAR AND THE OTHER ISLANDS OF THE WESTERN INDIAN OCEAN (THE COMORO AND MASCARENE ISLANDS, AND THE SEYCHELLES)1  

PubMed Central

A taxonomic revision of the genus Gouania Jacq. (Rhamnaceae) is presented for Madagascar and the other western Indian Ocean islands. Seventeen species are recognized, of which nine are described and published as new (all endemic to Madagascar): G. ambrensis Buerki, Phillipson & Callm., G. callmanderi Buerki, G. cupreifolia Buerki, Phillipson & Callm., G. cupuliflora Buerki, Phillipson & Callm., G. gautieri Buerki, Phillipson & Callm., G. perrieri Buerki, Phillipson & Callm., G. phillipsonii Buerki, G. taolagnarensis Buerki, Phillipson & Callm., and G. zebrifolia Buerki, Phillipson & Callm. Sixteen species occur in Madagascar, of which 13 are endemic and three are common to Madagascar and one or more of the smaller Indian Ocean islands. The latter include G. laxiflora Tul., a species which is also present on mainland Africa. One species, G. mauritiana Lam., is endemic to Runion Island. We recognize two subspecies within G. scandens (Gaertn.) R. B. Drumm.: G. scandens subsp. scandens and G. scandens subsp. glandulosa (Boivin ex Tul.) Buerki, Phillipson & Callm., the latter transferred from G. glandulosa Boivin ex Tul. Past confusion about the identity of this species is discussed. Five names are lectotypified: G. aphrodes Tul., G. glandulosa [= G. scandens subsp. glandulosa], G. laxiflora, G. lineata Tul., and G. tiliifolia Lam. Both lectotype and epitype are designated for G. mauritiana. Conservation assessments are provided for all species within their primary areas of occurrence. PMID:22053117

Buerki, Sven; Phillipson, Peter B.; Callmander, Martin W.

2011-01-01

353

Habitat structure and proximity to forest edge affect the abundance and distribution of forest-dependent birds in tropical coastal forests of southeastern Madagascar  

Microsoft Academic Search

Despite the fact that Madagascar is classified a biological `hotspot' due to having both high levels of species endemism and high forest loss, there has been no published research on how Madagascan bird species respond to the creation of a forest edge or to degradation of their habitat. In this study, we examined how forest bird communities and different foraging

James E. M. Watson; Robert J. Whittaker; Terence P. Dawson

2004-01-01

354

A new tree hole breeding Anodonthyla (Chordata: Anura: Microhylidae: Cophylinae) from low-altitude rainforests of the Masoala Peninsula, northeastern Madagascar  

Microsoft Academic Search

We describe a new arboreal, cophyline, microhylid frog from the rainforest of northeastern Madagascar belonging to the genus Anodonthyla. Anodonthyla hutchisoni, new species, is named in honor of a lifetime of dedication to excellence in herpetology by V. H. Hutchison. Anodonthyla hutchisoni differs from a close relative, A. boulengeri, in having generally larger morphometric features and in aspects of pattern

Dant B. Fenolio; Mark E. Walvoord; Jim F. Stout; Jasmin E. Randrianirina; Franco Andreone

2007-01-01

355

Detrital footprint of the Mozambique ocean: U/Pb SHRIMP and Pb evaporation zircon geochronology of metasedimentary gneisses in eastern Madagascar  

NASA Astrophysics Data System (ADS)

U-Pb Sensitive High-mass Resolution Microprobe (SHRIMP) and Pb evaporation analyses of detrital zircons from metasedimentary rocks in eastern Madagascar reveal that: 1) The protoliths of many of these rocks were deposited between 800 and 550 Ma; 2) these rocks are sourced from regions with rocks that date back to over 3400 Ma, with dominant age populations of 3200--3000 Ma, 2650 Ma, 2500 Ma, and 800--700 Ma. The Dharwar Craton of southern India is a potential source region for these sediments, as here rocks date back to over 3400 Ma and include abundant gneissic rocks with protoliths older than 3000 Ma, sedimentary rocks deposited at 3000--2600 Ma and granitoids that crystallised at 2513--2552 Ma. The 800-700 Ma zircons could potentially be sourced from elsewhere in India or from the Antananarivo Block of central Madagascar in the latter stages of closure of the Mozambique Ocean. The region of East Africa adjacent to Madagascar in Gondwana reconstructions (the Tanzania craton) is rejected as a potential source as there are no known rocks here older than 3000 Ma, and no detrital grains in our samples sourced from Mesoproterozoic and early Neoproterozoic rocks that are common throughout central east Africa. In contrast, coeval sediments 200 km west, in the Itremo sheet of central Madagascar, have detrital zircon age profiles consistent with a central East African source, suggesting that two late Neoproterozoic provenance fronts crop out in east Madagascar at approximately the position of the Betsimisaraka suture. These observations support an interpretation that the Betsimisaraka suture separates rocks that were derived from different locations within, or at the margins of, the Mozambique Ocean basin and therefore, that the suture is the site of subduction of a strand of Mozambique Ocean crust.

Collins, A. S.; Krner, A.; Fitzsimons, I. C. W.; Razakamanana, T.; Windley, B. F.

2003-04-01

356

Mesoscale eddy variability in the southern extension of the East Madagascar Current: Seasonal cycle, energy conversion terms, and eddy mean properties  

NASA Astrophysics Data System (ADS)

this study, we used more than 17 years of satellite altimetry observations and output from an ocean model to investigate the mesoscale eddy variability and forcing mechanisms to the south of Madagascar. Analysis of energy conversion terms in the model has shown seasonality on eddy formation, both by barotropic and baroclinic instabilities: maximum in winter (JJA) and minimum in summer (DJF). The eddies were mainly formed in the upper ocean (0-300 m) and at intermediate depths (800-2000 m) by barotropic and baroclinic instabilities, respectively. The former dominated in the southeastern margin of Madagascar, and the latter to the southwest, where the South-East Madagascar Current (SEMC) separates from the continental shelf. Seasonality of the eddy formation appeared linked with the seasonal intensification of the SEMC. The energy conversion terms indicated that the eddies have a significant contribution to the large-scale circulation, but not being persistent throughout the year, occurring mainly during the fall season (MAM). Eddy demography from altimetry and model provided information on eddy preferential sites for birth, annual occurrence (6-13 per year), eddy mean diameter (124-178 km), mean amplitude (9-28 cm), life-time (90-183 days), and maximum traveling distances (325-1052 km). Eddies formed to the southwest of Madagascar exhibited distinct characteristics from those formed in the southeast. Nevertheless, all eddies were highly nonlinear, suggesting that they are potential vectors of connectivity between Madagascar and Africa. This may have a significant impact on the ecology of this region.

Halo, Issufo; Penven, Pierrick; Backeberg, Bjrn; Ansorge, Isabelle; Shillington, Frank; Roman, Raymond

2014-10-01

357

Proximal and distal styles of pegmatite-related metasomatic emerald mineralization at Ianapera, southern Madagascar  

NASA Astrophysics Data System (ADS)

The Ianapera emerald deposit is located in the Neoproterozoic Vohibory Block of southern Madagascar. The local geology consists of intercalated migmatitic gneissic units and calcareous metasedimentary rocks, containing boudinaged metamorphosed mafic/ultramafic lenses, all intruded by pegmatite veins. These units occur near the hinge of the tightly folded Ianapera antiform, within a few kilometers of the Ampanihy shear zone. Emerald mineralization is hosted by metasomatic phlogopite veins, and bodies developed within the mafic/ultramafic rocks. Based on field and textural relationships, we distinguish proximal and distal styles of mineralization. Proximal mineralization occurs at the contact of pegmatite veins with mafic/ultramafic units; in the distal style, pegmatites are not observed. Three types of emeralds could be distinguished, mainly on the basis of color and mineral zoning. Some of these emeralds have the most Al-depleted and Cr-rich composition ever recorded. Another characteristic feature to the Ianapera deposit and, to our knowledge, yet unreported, is the association of some emeralds with scapolite in metasomatised mafic rocks. Mineral inclusions are common in most emeralds and include phlogopite, carbonates, barite, K-feldspar, quartz, pyrite, zircon, monazite, bastnaesite, phenakite, plus Fe and Cr oxides. However, feldspar and rare earth element-bearing minerals occur predominantly in proximal emeralds, which also have a more incompatible trace-element signature than distal emeralds. We propose a model related to syn- to post-tectonic magmatic-hydrothermal activity. Pegmatitic bodies intruded units of the Ianapera antiform probably during tectonic relaxation. Exsolution of fluids rich in halogens and incompatible elements from the cooling pegmatites caused hydrothermal metasomatism of Cr-bearing mafic/ultramafic rocks in direct contact with the pegmatites. Local fracturing favored fluid infiltration, permitting the formation of distal mineralization. Emerald composition was controlled by the chemistry of the host rock. The presence of carbonate mineral inclusions in the emeralds and the high F-activity indicated by elevated F-contents in newly formed minerals suggest transport of Be as a fluoride-carbonate complex. It seems likely that beryl formation was triggered by precipitation of F-rich phlogopite, which removed the complexing ligand from the fluid.

Andrianjakavah, Prosper Rakotovao; Salvi, Stefano; Bziat, Didier; Rakotondrazafy, Michel; Giuliani, Gaston

2009-10-01

358

Risk factors for avian influenza and Newcastle disease in smallholder farming systems, Madagascar highlands.  

PubMed

Newcastle disease (ND) and avian influenza (AI) are issues of interest to avian producers in Madagascar. Newcastle disease virus (NDV) is the major constraint for village aviculture, and avian influenza viruses type A (AIAV) are known to circulate in bird flocks. This study aims at classifying smallholder poultry farms, according to the combination of risk factors potentially associated with NDV and AIAV transmission and to assess the level of infection for each farm class. Two study sites, Lake Alaotra and Grand Antananarivo, were chosen with respect to their differences in terms of agro-ecological features and poultry productions. A typology survey involving 526 farms was performed to identify possible risk factors for (i) within-village, and (ii) between-village virus transmission. A cross-sectional serological study was also carried out in 270 farms to assess sero-prevalences of NDV and AIAV for each farm class and the link between them and risk factor patterns. For within-village transmission, four classes of farms were identified in Grand Antananarivo and five in Lake Alaotra. For between-village virus transmission, four classes of farms were identified for each site. In both sites, NDV sero-prevalence was higher than for AIAV. There was no evidence of the presence of H5 or H7 subtypes of AIAV. Sero-prevalences were significantly higher in Lake Alaotra than in Grand Antananarivo for both viruses (OR=2.4, p=0.02 for NDV, and OR=9.6, p<0.0001 for AIAV). For within-village NDV transmission in Grand Antananarivo, backyard chicken farms (OR=3.6, p<0.001), and chicken farms with biosecurity awareness (OR=3.4, p<0.01) had greater odds of having antibodies against NDV than the others. For between-village virus transmission, farms with multiple external contacts, and farms using many small markets had greater odds of having antibodies against NDV than the others (OR=5.4, p<0.01). For AIAV, there were no differences in sero-prevalences among farm classes. In Lake Alaotra, the observed high density of palmipeds and widespread rice paddies were associated with high sero-prevalences for both viruses, and a homogeneous risk of virus transmission between the different farm classes. In Grand Antananarivo, farm visits by collectors or animal health workers, and farm contacts with several markets were identified as potential risk factors for NDV transmission. Further studies are needed to identify the circulating virus genotypes, model their transmission risk, and provide adapted control measures. PMID:22130311

Rasamoelina Andriamanivo, H; Lancelot, R; Maminiaina, O F; Rakotondrafara, T F; Jourdan, M; Renard, J F; Gil, P; Servan de Almeida, R; Albina, E; Martinez, D; Tillard, E; Rakotondravao, R; Chevalier, V

2012-04-01

359

Ethnobotanical and economic value of Ravenala madagascariensis Sonn. in Eastern Madagascar  

PubMed Central

Background Known worldwide as the travelers tree, the Malagasy endemic species Ravenala madagascariensis Sonn. (Strelitziaceae) is considered as an iconic symbol of Madagascar. It is a widespread species in the eastern part of the country with four different varieties which are well represented in Ambalabe community. All of them are used for different purposes and the species represents an important cultural value in the lives of the local population. However, uses of Ravenala are only generally well known by local population. Thus, in this study, we report on the different uses of Ravenala and its importance to the Ambalabe local people. Methods Semi-structured interviews among 116 people, 59 men and 57 women with ages ranging from 17 to 84years old, free listing and market surveys were conducted in order to collect the vernacular names, the uses of Ravenala madagascariensis and the price of plant parts sold in local market. Then, the uses were categorized according to Cmara-Leret et al. classification. Results Different parts of the plant are currently used by local population, which are grouped as heart, trunk, leaves, petioles and rachis. Seven categories of use were recorded, most cited include: human food, utensils and tools, and house building. The most commonly used parts are trunk, heart, leaves and petioles for which the price varies between $3-15. Uses mentioned for construction (floor, roofs and wall), human food and utensils and tools are the most frequent and salient for local population. But the use of the plant as first materials for house building is revealed to be the most important for them. Conclusions Ravenala madagascariensis is very important to the Ambalabe communities because for local population, it represents the Betsimisaraka cultural and traditional use of the plant for house building. Moreover, none of its parts are discarded. The harvest and sale of R. madagascariensis for building materials can also provide an additional source of income to the family. Besides, using Ravenala in house construction reduces the use of slow growing trees and contributes to the sustainable use of natural forest resources. PMID:25027625

2014-01-01

360

Consuming sex: the association between modern goods, lifestyles and sexual behaviour among youth in Madagascar  

PubMed Central

Background Ethnographic evidence suggests that transactional sex is sometimes motivated by youths interest in the consumption of modern goods as much as it is in basic survival. There are very few quantitative studies that examine the association between young peoples interests in the consumption of modern goods and their sexual behaviour. We examined this association in two regions and four residence zones of Madagascar: urban, peri-urban and rural Antananarivo, and urban Antsiranana. We expected risky sexual behaviour would be associated with interests in consuming modern goods or lifestyles; urban residence; and socio-cultural characteristics. Methods We administered a population-based survey to 2, 255 youth ages 1524 in all four residence zones. Focus group discussions guided the survey instrument which assessed socio-demographic and economic characteristics, consumption of modern goods, preferred activities and sexual behaviour. Our outcomes measures included: multiple sexual partners in the last year (for men and women); and ever practicing transactional sex (for women). Results Overall, 7.3% of women and 30.7% of men reported having had multiple partners in the last year; and 5.9% of women reported ever practicing transactional sex. Bivariate results suggested that for both men and women having multiple partners was associated with perceptions concerning the importance of fashion and a series of activities associated with modern lifestyles. A subset of lifestyle characteristics remained significant in multivariate models. For transactional sex bivariate results suggested perceptions around fashion, nightclub attendance, and getting to know a foreigner were key determinants; and all remained significant in multivariate analysis. We found peri-urban residence more associated with transactional sex than urban residence; and ethnic origin was the strongest predictor of both outcomes for women. Conclusions While we found indication of an association between sexual behaviour and interest in modern goods, or modern lifestyles, such processes did not single-handedly explain risky sexual behaviour among youth; these behaviours were also shaped by culture and conditions of economic uncertainty. These determinants must all be accounted for when developing interventions to reduce risky transactional sex and vulnerability to HIV. PMID:23510104

2013-01-01

361

Entomological and parasitological impacts of indoor residual spraying with DDT, alphacypermethrin and deltamethrin in the western foothill area of Madagascar  

PubMed Central

Background In Madagascar, indoor residual spraying (IRS) with insecticide was part of the national malaria control programme since the middle of the twentieth century. It was mainly employed in the highlands and the foothill areas, which are prone to malaria epidemics. Prior to a policy change foreseeing a shift from DDT to pyrethroids, a study was carried out to assess the entomological and parasitological impacts of IRS in areas with DDT or pyrethroids and in areas without IRS. Methods The study was carried out from October 2002 to February 2005 in three communes of the western foothill area of Madagascar. Two communes received IRS with DDT in February 2003, then IRS with pyrethroids (alphacypermethrin or deltamethrin) in February 2004. The third commune remained untreated. Mosquitoes were collected at night using human landing catches and early in the morning in resting places. Blood smears were obtained from schoolchildren and microscopically examined for Plasmodium presence. Results In total, 18,168 human landing mosquitoes and 12,932 resting anophelines were collected. The Anopheles species caught comprised 10 species. The main and most abundant malaria vector was Anopheles funestus (72.3% of human-seeking malaria vectors caught indoors). After IRS had taken place, this species exhibited a lower human biting rate and a lower sporozoite index. Overall, 5,174 blood smears were examined with a mean plasmodic index of 19.9%. A total of four Plasmodium species were detected. Amongst tested school children the highest plasmodial index was 54.6% in the untreated commune, compared to 19.9% in the commune sprayed with DDT and 11.9% in the commune sprayed with pyrethroid. The highest prevalence of clinical malaria attacks in children present at school the day of the survey was 33% in the untreated commune compared to 8% in the areas which received IRS. Conclusion In terms of public health, the present study shows (1) a high efficacy of IRS with insecticide, (2) a similar efficacy of DDT and pyrethroid and (3) a similar efficacy of alphacypermethrin and deltamethrin. The use of IRS with DDT and pyrethroid greatly decreased the vector-human contact, with an associated decrease of the plasmodial index. However malaria transmission did not reach zero, probably due to the exophilic host-seeking and resting behaviours of the malaria vectors, thus avoiding contact with insecticide-treated surfaces indoors. The study highlights the strengths and weaknesses of the IRS implementation and the need for complementary tools for an optimal vector control in Madagascar. PMID:24423246

2014-01-01

362

Early initiation of and exclusive breastfeeding in large-scale community-based programmes in Bolivia and Madagascar.  

PubMed

About one-fourth to one-half of all infant deaths in developing countries occur in the first week of life. Immediate breastfeeding within the first hour, followed by early exclusive breastfeeding, improves the health and survival status of newborns. The aim of this study was to demonstrate that breastfeeding practices, crucial to infant health, can be improved at scale in developing countries. During 1999-2003, the LINKAGES Project, funded by the United States Agency for International Development, implemented its community-based model to bring about rapid change in individual behaviours and community norms regarding early and exclusive breastfeeding, at a scale [LINKAGES' definition of 'scale' was adapted from a CORE Group background paper on 'Scaling-up' maternal, newborn, and child health services, 11 July 2005] that could achieve significant public-health impact. 'Scale' was defined as bringing improved infant-feeding practices to more people over a wider geographic area, more quickly, more equitably, and with sustainability as a goal. During this time, country-specific programmes were designed and implemented in Bolivia and Madagascar, with catchment populations of one million and six million respectively. These country programmes were implemented with multiple local government, private voluntary organizations, and partners of non-governmental organizations (NGOs) through existing health and nutrition activities. Breastfeeding was an entry point to work at all levels of the healthcare system and, within communities, using policy/advocacy and training for healthcare workers, with a particular emphasis on front-line health workers and community members. Harmonized messages and materials, including mass media, were developed and used by partners. Timely initiation of breastfeeding was one indicator measured. Data collected through rapid assessment surveys showed statistically significant increases (p<0.001) in timely initiation of breastfeeding in both the countries. In Bolivia, timely initiation of breastfeeding went from 56% in 2000 to 69% in 2001 and reached 74% by the end of 2003. In Madagascar, the initiation rate went from 34% at baseline in 2000 to 69% in 2001, 76% in 2002, and rose to 78% in 2004. Exclusive breastfeeding during the first month of life was also measured. At baseline in Bolivia, the rate of exclusive breastfeeding for the first month of life was 81% (2000), decreased slightly in 2001, and then increased to 88% by the end of the Project in 2003. In Madagascar, it started high at 86% in 2000, increased during the implementation of the programme, and by 2004, was 91%. These results were achieved quickly and sustained over the course of the intervention. PMID:17591350

Baker, Elizabeth Jean; Sanei, Linda C; Franklin, Nadra

2006-12-01

363

Seasonal changes in general activity, body mass and reproduction of two small nocturnal primates: a comparison of the golden brown mouse lemur ( Microcebus ravelobensis) in Northwestern Madagascar and the brown mouse lemur ( Microcebus rufus) in Eastern Madagascar.  

PubMed

To investigate for the first time the relationship between contrasting patterns of seasonal changes of the environment and activity, body mass and reproduction for small nocturnal primates in nature, we compared a population of golden brown mouse lemur ( Microcebus ravelobensis) in a dry deciduous forest of northwestern Madagascar and of the brown mouse lemur ( Microcebus rufus) in an evergreen rain forest of eastern Madagascar. Both species live under similar photoperiodic conditions. Golden brown mouse lemurs (GBML) were active during the whole period (May to December) irrespective of changing environmental conditions. In contrast, a part of the population of brown mouse lemurs (BML) showed prolonged seasonal torpor, related to body mass during periods of short day length and low ambient temperatures. Differences between species might be due to differences in ambient temperature and food supply. Body weight and tail thickness (adipose tissue reserve) did not show prominent differences between short and long photoperiods in GBML, whereas both differ significantly in BML, suggesting species-specific differences in the photoperiodically driven control of metabolism. Both species showed a seasonal reproduction. The rate of growth and size of the testes were similar and preceded estrous onset in both species suggesting a photoperiodic control of reproduction in males. The estrous onset in females occurred earlier in GBML than in BML. Estrous females were observed over at least 4 months in the former, but in only 1 month in the latter species. Intraspecific variation of estrous onset in GBML may be explained by body mass. Interspecific variation of female reproduction indicates species-specific differences in the control of reproduction. Thus, environmentally related differences in annual rhythms between closely related small nocturnal lemurs emerged that allow them to cope with contrasting patterns of seasonal changes in their habitats. PMID:14593515

Randrianambinina, Blanchard; Rakotondravony, Daniel; Radespiel, Ute; Zimmermann, Elke

2003-10-01

364

lsothennes d'hiver ausrml Madagascar(moyennedu mois d'aot), d'aprs Le Bourdiccetal. (1969)et Le ravenala dans ses environnements. emplacements des deux transccts ouest-est (Andasibe-Brickaville et Ranomafana-Mananjary) o De haut en bas : en fort, sur une  

E-print Network

lsothennes d'hiver ausrml à Madagascar(moyennedu mois d'août), d'après Le Bourdiccetal. (1969)et Le IDadik: et Claude Marcel Hladik* PREMI?RE PARTIE Le ravenala est une plante endémique deMadagascar, bien, dans la forêt d'Andasibe (à l'est de Madagascar), de deux popu- lations de ravenala différant

Paris-Sud XI, Université de

365

Forecasting deforestation and carbon emissions in tropical developing countries facing demographic expansion: a case study in Madagascar  

PubMed Central

Anthropogenic deforestation in tropical countries is responsible for a significant part of global carbon dioxide emissions in the atmosphere. To plan efficient climate change mitigation programs (such as REDD+, Reducing Emissions from Deforestation and forest Degradation), reliable forecasts of deforestation and carbon dioxide emissions are necessary. Although population density has been recognized as a key factor in tropical deforestation, current methods of prediction do not allow the population explosion that is occurring in many tropical developing countries to be taken into account. Here, we propose an innovative approach using novel computational and statistical tools, including R/GRASS scripts and the new phcfM R package, to model the intensity and location of deforestation including the effect of population density. We used the model to forecast anthropogenic deforestation and carbon dioxide emissions in five large study areas in the humid and spiny-dry forests of Madagascar. Using our approach, we were able to demonstrate that the current rapid population growth in Madagascar (+3.39% per year) will significantly increase the intensity of deforestation by 2030 (up to +1.17% per year in densely populated areas). We estimated the carbon dioxide emissions associated with the loss of aboveground biomass to be of 2.24 and 0.26 tons per hectare and per year in the humid and spiny-dry forest, respectively. Our models showed better predictive ability than previous deforestation models (the figure of merit ranged from 10 to 23). We recommend this approach to reduce the uncertainty associated with deforestation forecasts. We also underline the risk of an increase in the speed of deforestation in the short term in tropical developing countries undergoing rapid population expansion. PMID:23789079

Vieilledent, Ghislain; Grinand, Clovis; Vaudry, Romuald

2013-01-01

366

Late Quaternary history of the Vakinankaratra volcanic field (central Madagascar): insights from luminescence dating of phreatomagmatic eruption deposits  

NASA Astrophysics Data System (ADS)

The Quaternary Vakinankaratra volcanic field in the central Madagascar highlands consists of scoria cones, lava flows, tuff rings, and maars. These volcanic landforms are the result of processes triggered by intracontinental rifting and overlie Precambrian basement or Neogene volcanic rocks. Infrared-stimulated luminescence (IRSL) dating was applied to 13 samples taken from phreatomagmatic eruption deposits in the Antsirabe-Betafo region with the aim of constraining the chronology of the volcanic activity. Establishing such a chronology is important for evaluating volcanic hazards in this densely populated area. Stratigraphic correlations of eruption deposits and IRSL ages suggest at least five phreatomagmatic eruption events in Late Pleistocene times. In the Lake Andraikiba region, two such eruption layers can be clearly distinguished. The older one yields ages between 109 15 and 90 11 ka and is possibly related to an eruption at the Amboniloha volcanic complex to the north. The younger one gives ages between 58 4 and 47 7 ka and is clearly related to the phreatomagmatic eruption that formed Lake Andraikiba. IRSL ages of a similar eruption deposit directly overlying basement laterite in the vicinity of the Fizinana and Ampasamihaiky volcanic complexes yield coherent ages of 68 7 and 65 8 ka. These ages provide the upper age limit for the subsequently developed Iavoko, Antsifotra, and Fizinana scoria cones and their associated lava flows. Two phreatomagmatic deposits, identified near Lake Tritrivakely, yield the youngest IRSL ages in the region, with respective ages of 32 3 and 19 2 ka. The reported K-feldspar IRSL ages are the first recorded numerical ages of phreatomagmatic eruption deposits in Madagascar, and our results confirm the huge potential of this dating approach for reconstructing the volcanic activity of Late Pleistocene to Holocene volcanic provinces.

Rufer, Daniel; Preusser, Frank; Schreurs, Guido; Gnos, Edwin; Berger, Alfons

2014-05-01

367

Assessing Water Management of Mining Effluent Using Temporal and Spatial Hydrologic Analyses: The Case of QIT Madagascar Minerals  

NASA Astrophysics Data System (ADS)

Associated with the commencement of any water-intensive mining operation is the formation of a set of policies, standards, and sampling protocols that guide the management of all water resources connected to the mining facility, surrounding environment, and affected communities. This study explores the interface between corporate water management and hydrologic methods by evaluating changes in water quality over the course of the mining cycle at QIT Madagascar Minerals (QMM) in Tolagnaro, Madagascar. Sampling and lab research of processed water were conducted following established QMM procedures and then analyzed in conjunction with the complete QMM water quality database. Water quality was analyzed spatially to exhibit how processed water changes as it moves throughout the mining cycle before release into the environment. Graphical representation of the spatial changes in various parameters exhibit deterioration in water quality relative to the source, improvement in quality before being released as effluent, and natural remediation by wetlands before discharge into the Mandromondromotra River. In addition, water quality parameters were evaluated temporally, using data supplied by QMM's Service de l'Eau et Dchets. Yearly and monthly comparisons of hydrological parameters highlight data gaps, the effects of seasonality, and the evolution of water quality monitoring at QMM. Technical evaluation of processed water as it flows through the mining system provides insight into how water monitoring and management can best be adapted at the corporate level to prevent negative impacts on the environment. Water quality data for various parameters from April 2013 at each of the sampling locations. The graphs highlight spatial changes in parameters as water moves from the sources (WD90, Paddock 3), to sites on the mine (500M, Basmin, SCC2), to release points (WMC703, WMC803), to discharge points into the MMM River.

Hoagland, N. E.

2013-12-01

368

Stratigraphic Analysis of Upper Cretaceous Rocks in the Mahajanga Basin, Northwestern Madagascar: Implications for Ancient and Modern Faunas.  

PubMed

Upper Cretaceous strata of the Mahajanga Basin, northwestern Madagascar, yield some of the most significant and exquisitely preserved vertebrate fossils known from Gondwana. The sedimentology of these strata and their stratigraphic relations have been the focus of renewed geological investigations during the course of five expeditions since 1993. We here designate stratotypes and formalize the terrestrial Maevarano Formation, with three new members (Masorobe, Anembalemba, Miadana), and the overlying marine Berivotra Formation. The Maevarano Formation accumulated on a broad, semiarid alluvial plain bounded to the southeast by crystalline highlands and to the northwest by the Mozambique Channel. The Berivotra Formation was deposited in an open marine setting that evolved from a clastic- to a carbonate-dominated shelf, resulting in deposition of the overlying Betsiboka limestone of Danian age. New stratigraphic data clearly indicate that the Maevarano Formation correlates, at least in part, with the Maastrichtian Berivotra Formation, and this in turn indicates that the most fossiliferous portions of the Maevarano Formation are Maastrichtian in age, rather than Campanian as previously reported. This revised age for the Maevarano vertebrate assemblage indicates that it is approximately contemporaneous with the vertebrate fauna recovered from the Deccan basalt volcano-sedimentary sequence of India. The comparable age of these two faunas is significant because the faunas appear to be more similar to one another than either is to those from any other major Gondwanan landmass. The revised age of the Maevarano Formation, when considered in the light of our recent fossil discoveries, further indicates that the ancestral stocks of Madagascar's overwhelmingly endemic modern vertebrate fauna arrived on the island in post-Mesozoic times. The basal stocks of the modern vertebrate fauna are conspicuously absent in the Maevarano Formation. Finally, the revised age of the Maevarano Formation serves to expand our global perspective on the K/T event by clarifying the age of a diverse, and arguably the best preserved, sample of Gondwanan vertebrates from the terminal Cretaceous. PMID:10769157

Rogers; Hartman; Krause

2000-05-01

369

A revision of the genus Herminella Spaeth (Chrysomelidae: Cassidinae:Notosacanthini), with a description of a new related genus and species from Madagascar.  

PubMed

The genus Herminella Spaeth from southern Africa is revised. It comprises four species: Herminella liliputana Spaeth and H. marshalli Spaeth are redescribed and two species are described as new-H. quadrimaculata from South Africa and H. flavocostata from Nambia and South Africa. A new related genus and species Hermosacantha madagascarica from Madagascar is described. Members of both genera belong to the smallest world cassids. PMID:25543568

Borowiec, Lech; Wietojaska, Jolanta

2014-01-01

370

Natural Disasters and Primate Populations: The Effects of a 2Year Drought on a Naturally Occurring Population of Ring-Tailed Lemurs ( Lemur catta ) in Southwestern Madagascar  

Microsoft Academic Search

We examine demographic patterns from a long-term study (19871996) of the population of ring-tailed lemurs in the Beza-Mahafaly Special Reserve, in southwestern Madagascar. In particular, we focus on the effects that a severe drought in 1991 and 1992 had on the population. The population of adult animals peaked in 1991 but decreased rapidly during the subsequent drought and immediate postdrought

Lisa Gould; Robert W. Sussman; Michelle L. Sauther

1999-01-01

371

A review of agricultural research issues raised by the system of rice intensification (SRI) from Madagascar: opportunities for improving farming systems for resource-poor farmers  

Microsoft Academic Search

The system of rice intensification (SRI) that evolved in the 1980s and 1990s in Madagascar permits resource-limited farmers to realise yields of up to 15 t of paddy\\/hectare on infertile soils, with greatly reduced rates of irrigation and without external inputs. This paper reviews the plant physiological and bio-ecological factors associated with agronomic practices that could explain the extraordinary yields

Willem A. Stoop; Norman Uphoff; Amir Kassam

2002-01-01

372

Mountain refugia play a role in soil arthropod speciation on Madagascar: a case study of the endemic giant fire-millipede genus Aphistogoniulus.  

PubMed

To elucidate the speciation mechanisms prevalent within hotspots of biodiversity, and the evolutionary processes behind the rise of their species-rich and endemic biota, we investigated the phylogeny of the giant fire-millipede genus Aphistogoniulus Silvestri, 1897, a Malagasy endemic. This study is the first comprehensive (molecular and morphological) phylogenetic study focusing on millipede (class Diplopoda) speciation on Madagascar. The morphological analysis is based on 35 morphological characters and incorporates ten described as well as two newly described species (A. rubrodorsalisn. sp. and A. jeekelin. sp.) of Aphistogoniulus. The molecular analysis is based on both mitochondrial (COI and 16S), and nuclear genes (complete 18S rDNA), together comprised of 3031 base pairs, which were successfully sequenced for 31 individual specimens and eight species of Aphistogoniulus. In addition to the null-model (speciation by distance), two diversification models, mountain refugia and ecotone shift, were discovered to play a role in the speciation of soil arthropods on Madagascar. Mountain refugia were important in the speciation of the A. cowani clade, with three species occurring in the Andringitra and Ranomafana Mountains in the southeast (A. cowani), the Ambohijanahary and Ambohitantely Mountains in the mid-west (A. sanguineus), and the Marojejy Mountain in the northeast (A. rubrodorsalisn. sp.). An ecotone shift from the eastern rainforest to the unique subarid spiny forest of Mahavelo was discovered in the A. vampyrus-A. aridus species-pair. In the monophyletic A. diabolicus clade, evidence for divergent evolution of sexual morphology was detected: species with greatly enlarged gonopods are sister-taxa to species with normal sized gonopods. Among the large-bodied Spirobolida genera of Madagascar, Colossobolus and Sanguinobolus were found to be close sister-genera to Aphistogoniulus. Forest destruction has caused forest corridors between populations to disappear, which might limit the possible resolution of biogeographic analyses on Madagascar. PMID:22162998

Wesener, Thomas; Raupach, Michael J; Decker, Peter

2011-01-01

373

A new species of the Boophis rappiodes group (Anura, Mantellidae) from the Sahamalaza Peninsula, northwest Madagascar, with acoustic monitoring of its nocturnal calling activity  

PubMed Central

Abstract A new species of treefrog of the Boophis rappiodes group (Anura, Mantellidae) is described from the Sahamalaza Iles Radama National Park in northwest Madagascar. This new species is green in colour with bright red speckling across its head and dorsum; similar in morphology to other species of this group including: B. bottae, B. rappiodes, B. erythrodactylus and B. tasymena. The new species can be distinguished by its advertisement call and by a genetic divergence of more than 4.9% in the analysed mitochondrial 16S rRNA gene fragment. Its call consists of two note types: a trill and a click; although similar sounding to B. bottae, the trill note of the new species has a faster pulse rate while the click note is predominantly two-pulsed rather than three. All individuals were detected from the banks of two streams in Ankarafa Forest. The new species represents the only member of the B. rappiodes group endemic to Madagascars western coast, with the majority of other members known from the eastern rainforest belt. Despite its conspicuous call, it has not been detected from other surveys of northwest Madagascar and it is likely to be a local endemic to the peninsula. The ranges of two other amphibian species also appear restricted to Sahamalaza, and so the area seems to support a high level of endemicity. Although occurring inside a National Park, this species is highly threatened by the continuing decline in the quality and extent of its habitat. Due to these threats it is proposed that this species should be classified as Critically Endangered according to the IUCN Red List criteria. PMID:25152689

Penny, Samuel G.; Andreone, Franco; Crottini, Angelica; Holderied, Marc W.; Rakotozafy, Lovasoa Sylviane; Schwitzer, Christoph; Rosa, Gonalo M.

2014-01-01

374

The influence of certain taxonomic and environmental parameters on biomass production and triterpenoid content in the leaves of Centella asiatica (L.) Urb. from Madagascar.  

PubMed

Centella asiatica (Apiaceae family; Talapetraka in Malagasy) is a tropical and subtropical plant with leaves containing glycotriterpenoids (asiaticosides) used in traditional and modern medicine. C. asiatica is collected exclusively in natural stands. It is Madagascar's second most important indigenous plant export. The objective in this study is to provide data which will make it possible to optimize the harvest and thus effectively develop this resource. Two foliar morphotypes were identified: morphotype A with small reniform leaves (leaf area ca. 4.5 cm(2) ), found in the east of Madagascar, and morphotype B with large round leaves (up to 7.5 cm(2) ) found in the west, with sympatric zones in the central part of the island. Morphotype A produces a higher biomass, and is twice as rich in asiaticosides as morphotype B. Significant variations in biomass yield and asiaticoside content are observed depending on the date of collection: higher during the rainy season (December to April) and lower during the dry season (June to August). Inter-annual variations are also observed. Populations located at around 800-1400 m altitude on the eastern side of Madagascar, in a sub-humid climate, appeared to be more productive. These results provide more precise information to the economic sector, which confirms the empirical choices made by collectors. They represent the first elements towards sustainable management of the resource, and maybe even domestication. PMID:22344906

Rahajanirina, Voninavoko; Raoseta, Soaharin'ny Ony Rakotondralambo; Roger, Edmond; Razafindrazaka, Harena; Pirotais, Sarah; Boucher, Marie; Danthu, Pascal

2012-02-01

375

Structure and metamorphism of the granitic basement around Antananarivo: A key to the Pan-African history of central Madagascar and its Gondwana connections  

NASA Astrophysics Data System (ADS)

The Precambrian basement of Madagascar acquired a polyphase imprint during the Pan-African orogeny. In northern central Madagascar, emplacement of stratoid alkaline granites at midcrustal depth (4-5 kbars) led to formation of a layered crust in a postcollisional extensional regime at 630 Ma (D1). Subsequently, the structures of the stratoid granites were rotated by the sinistral and transpressive E-W Antananarivo flexure (or virgation) zone (D2). East of Antananarivo the structures of the D1 layered crust and the D2 virgation are crosscut by the steeply dipping N-S foliations of the Angavo belt. Lineations gently plunging to the north attest that the Angavo belt is a major strike-slip shear zone that formed under low-pressure granulitic conditions (3 kbars, 790C). The nearby porphyritic Carion granite was emplaced at the end of this period of N-S shearing (D3), which can thus be no younger than 530 Ma. Late-Pan-African (580-550 Ma) strike-slip motion along broadly N-S shear zones has been recognized elsewhere in Madagascar and in its Gondwana connections. Continuation of the Angavo belt as one of the high strain belts of the Arabian-Nubian Shield is discussed in the general framework of Gondwana assembly.

NDLec, Anne; Ralison, Bruno; Bouchez, Jean-Luc; GrGoire, Vincent

2000-10-01

376

Phylogeographic analysis of the true lemurs (genus Eulemur) underlines the role of river catchments for the evolution of micro-endemism in Madagascar  

PubMed Central

Introduction Due to its remarkable species diversity and micro-endemism, Madagascar has recently been suggested to serve as a biogeographic model region. However, hypothesis-based tests of various diversification mechanisms that have been proposed for the evolution of the islands micro-endemic lineages are still limited. Here, we test the fit of several diversification hypotheses with new data on the broadly distributed genus Eulemur using coalescent-based phylogeographic analyses. Results Time-calibrated species tree analyses and population genetic clustering resolved the previously polytomic species relationships among eulemurs. The most recent common ancestor of eulemurs was estimated to have lived about 4.45 million years ago (mya). Divergence date estimates furthermore suggested a very recent diversification among the members of the brown lemur complex, i.e. former subspecies of E. fulvus, during the Pleistocene (0.33-1.43 mya). Phylogeographic model comparisons of past migration rates showed significant levels of gene flow between lineages of neighboring river catchments as well as between eastern and western populations of the redfronted lemur (E. rufifrons). Conclusions Together, our results are concordant with the centers of endemism hypothesis (Wilm et al. 2006, Science 312:10631065), highlight the importance of river catchments for the evolution of Madagascars micro-endemic biota, and they underline the usefulness of testing diversification mechanisms using coalescent-based phylogeographic methods. PMID:24228694

2013-01-01

377

Vertebrate time-tree elucidates the biogeographic pattern of a major biotic change around the K-T boundary in Madagascar.  

PubMed

The geographic and temporal origins of Madagascar's biota have long been in the center of debate. We reconstructed a time-tree including nearly all native nonflying and nonmarine vertebrate clades present on the island, from DNA sequences of two single-copy protein-coding nuclear genes (BDNF and RAG1) and a set of congruent time constraints. Reconstructions calculated with autocorrelated or independent substitution rates over clades agreed in placing the origins of the 31 included clades in Cretaceous to Cenozoic times. The two clades with sister groups in South America were the oldest, followed by those of a putative Asian ancestry that were significantly older than the prevalent clades of African ancestry. No colonizations from Asia occurred after the Eocene, suggesting that dispersal and vicariance of Asian/Indian groups were favored over a comparatively short period during, and shortly after, the separation of India and Madagascar. Species richness of clades correlates with their age but those clades that have a large proportion of species diversity in rainforests are significantly more species-rich. This finding suggests an underlying pattern of continuous speciation through time in Madagascar's vertebrates, with accelerated episodes of adaptive diversification in those clades that succeeded radiating into the rainforests. PMID:22431616

Crottini, Angelica; Madsen, Ole; Poux, Celine; Strauss, Axel; Vieites, David R; Vences, Miguel

2012-04-01

378

Vertebrate time-tree elucidates the biogeographic pattern of a major biotic change around the KT boundary in Madagascar  

PubMed Central

The geographic and temporal origins of Madagascar's biota have long been in the center of debate. We reconstructed a time-tree including nearly all native nonflying and nonmarine vertebrate clades present on the island, from DNA sequences of two single-copy protein-coding nuclear genes (BDNF and RAG1) and a set of congruent time constraints. Reconstructions calculated with autocorrelated or independent substitution rates over clades agreed in placing the origins of the 31 included clades in Cretaceous to Cenozoic times. The two clades with sister groups in South America were the oldest, followed by those of a putative Asian ancestry that were significantly older than the prevalent clades of African ancestry. No colonizations from Asia occurred after the Eocene, suggesting that dispersal and vicariance of Asian/Indian groups were favored over a comparatively short period during, and shortly after, the separation of India and Madagascar. Species richness of clades correlates with their age but those clades that have a large proportion of species diversity in rainforests are significantly more species-rich. This finding suggests an underlying pattern of continuous speciation through time in Madagascar's vertebrates, with accelerated episodes of adaptive diversification in those clades that succeeded radiating into the rainforests. PMID:22431616

Crottini, Angelica; Madsen, Ole; Poux, Celine; Strau, Axel; Vieites, David R.; Vences, Miguel

2012-01-01

379

Redescription of 'Polyzonium' malagassum, a new synonym ofRhinotus purpureus (Pocock, 1894), with notes about the occurrence of the order Polyzoniida on Madagascar (Diplopoda).  

PubMed

Polyzonium malagassum de Saussure & Zehntner, 1902, the only indigenous record of the order Polyzoniida from Madagascar, is redescribed after a study of the type specimens. The only male specimen is selected as the lectotype and illustrated. P. malagassum is discovered to be a synonym of the widespread tropical tramp species Rhinotus purpureus (Pocock, 1894). A mapping of additional locality data of R. pupureus shows that the species is widespread in Malagasy rainforests and montane rainforests, and occurs locally in high densities. Seven potentially indigenous Polyzoniida morphospecies also occur on Madagascar, but these undescribed species are more localized and show a lower abundance than R. purpureus. Brief notes, locality data, and Museum acronyms are given for the undescribed Polyzoniida species, which will hopefully assist future studies on Malagasy representatives of this little-known but biogeographically interesting order. With the discovery of the ubiquitous presence of R. purpureus on Madagascar, the similarity of the defense secretions of South American and of endemic Malagasy poison dart frogs (family Mantellidae) might derive from the fact that both groups prey on and sequester alkaloids from the same species of millipede. PMID:24869890

Wesener, Thomas

2014-01-01

380

Detrital footprint of the Mozambique ocean: U-Pb SHRIMP and Pb evaporation zircon geochronology of metasedimentary gneisses in eastern Madagascar  

NASA Astrophysics Data System (ADS)

The southern East African Orogen is a collisional belt where the identification of major suture zones has proved elusive. In this study, we apply U-Pb isotopic techniques to date detrital zircons from a key part of the East African Orogen, analyse their possible source region and discuss how this information can help in unravelling the orogen. U-Pb sensitive high-mass resolution ion microprobe (SHRIMP) and Pb evaporation analyses of detrital zircons from metasedimentary rocks in eastern Madagascar reveal that: (1) the protoliths of many of these rocks were deposited between 800 and 550 Ma; and (2) these rocks are sourced from regions with rocks that date back to over 3400 Ma, with dominant age populations of 3200-3000, 2650, 2500 and 800-700 Ma. The Dharwar Craton of southern India is a potential source region for these sediments, as here rocks date back to over 3400 Ma and include abundant gneissic rocks with protoliths older than 3000 Ma, sedimentary rocks deposited at 3000-2600 Ma and granitoids that crystallised at 2513-2552 Ma. The 800-700 Ma zircons could potentially be sourced from elsewhere in India or from the Antananarivo Block of central Madagascar in the latter stages of closure of the Mozambique Ocean. The region of East Africa adjacent to Madagascar in Gondwana reconstructions (the Tanzania craton) is rejected as a potential source as there are no known rocks here older than 3000 Ma, and no detrital grains in our samples sourced from Mesoproterozoic and early Neoproterozoic rocks that are common throughout central east Africa. In contrast, coeval sediments 200 km west, in the Itremo sheet of central Madagascar, have detrital zircon age profiles consistent with a central East African source, suggesting that two late Neoproterozoic provenance fronts pass through east Madagascar at approximately the position of the Betsimisaraka suture. These observations support an interpretation that the Betsimisaraka suture separates rocks that were derived from different locations within, or at the margins of, the Mozambique Ocean basin and therefore, that the suture is the site of subduction of a strand of Mozambique Ocean crust.

Collins, Alan S.; Krner, Alfred; Fitzsimons, Ian C. W.; Razakamanana, Thodore

2003-11-01

381

Depositional history and stratigraphical evolution of the Sakoa Group (Lower Karoo Supergroup) in the southern Morondava Basin, Madagascar  

NASA Astrophysics Data System (ADS)

The Sakoa Group is the lowermost stratigraphical succession of the Karoo Supergroup and the oldest sedimentary unit in Madagascar, spanning the Late Carboniferous through Early Permian epochs. The Sakoa Group is exposed in the southern Morondava Basin. It is predominantly a siliciclastic sequence comprising seven lithofacies associations: (1) diamictites; (2) conglomeratic sandstones; (3) sandstones; (4) interbedded thin sandstones and mudstones; (5) mudstones; (6) coals; and (7) limestones. These facies represent deposition in the early extensional stages of continental rift development. The sediments were deposited predominantly on alluvial fans, and in braided to meandering stream and overbank environments. Locally lacustrine and coal swamp environments formed in low areas of the basin floor during rift initiation. Subsidence rates remained fairly constant throughout the Early Permian and were accompanied by a gradual reduction in relief of the basin margins and an increased geomorphic maturity of the fluvial systems flowing across the basin floor. Near the end of the Early Permian the southern Morondava Basin was inundated by a marine transgression , which resulted in deposition of the Vohitolia Limestone. Subsequent tectonic uplift and erosion resulted in a regional unconformity between the Sakoa Group and the overlying Sakamena Group.

Wescott, William A.; Diggens, John N.

1997-05-01

382

Hydraulique des units d'interfluves et de bas-fond tourbeux: un exemple en zone de socle altr (Madagascar)  

NASA Astrophysics Data System (ADS)

The hydrodynamics of the groundwater system of the upland granito-gneissic plateau of Madagascar is governed by the structure of the underlying aquifer. In the alteritic interfluves, the aquifer has two layers; the peat aquifer is multilayered. Groundwater levels and spring discharges observed over 3 successive years distinguish between two different types of hydraulic behaviour. (1) Under the interfluves, unconfined conditions are found in allochtonous weathered material, and semi-confined conditions in the autochtonous weathered basement. These two systems are separated by a semi-permeable clay layer. The first system responds rapidly to rainfall (approximately 15 days) whereas the second system responds more slowly (approximately 3 months). This leads to a vertical flux between the two aquifers, the direction of which depends on the season; at the beginning of the wet season the flux is downwards, but during the later part of the season the direction reverses. (2) In the low-lying regions, where sequences are superimposed, the direction of the vertical flow changes several times over a year. At the beginning of the wet season the flux is downwards, it reverses at the end of the season. A downwards flux is then observed towards the second part of the dry season. Such behaviour is only observed in the lowest third of the catchment where permeable silts take the place of less permeable peat. This pattern of fluxes suggests a close relationship between surface water and groundwater regimes, and has a major influence on the individual water balances of the two systems.

Grillot, J. C.; Dussarrat, B.

1992-07-01

383

Ornamental Exterior versus Therapeutic Interior of Madagascar Periwinkle (Catharanthus roseus): The Two Faces of a Versatile Herb  

PubMed Central

Catharanthus roseus (L.) known as Madagascar periwinkle (MP) is a legendary medicinal plant mostly because of possessing two invaluable antitumor terpenoid indole alkaloids (TIAs), vincristine and vinblastine. The plant has also high aesthetic value as an evergreen ornamental that yields prolific blooms of splendid colors. The plant possesses yet another unique characteristic as an amiable experimental host for the maintenance of the smallest bacteria found on earth, the phytoplasmas and spiroplasmas, and serves as a model for their study. Botanical information with respect to synonyms, vernacular names, cultivars, floral morphology, and reproduction adds to understanding of the plant while the geography and ecology of periwinkle illustrate the organism's ubiquity. Good agronomic practices ensure generous propagation of healthy plants that serve as a source of bioactive compounds and multitudinous horticultural applications. The correlation between genetic diversity, variants, and TIA production exists. MP is afflicted with a whole range of diseases that have to be properly managed. The ethnobotanical significance of MP is exemplified by its international usage as a traditional remedy for abundant ailments and not only for cancer. TIAs are present only in micro quantities in the plant and are highly poisonous per se rendering a challenge for researchers to increase yield and reduce toxicity.

Valdiani, Alireza; Cahill, David; Tan, Yee-How; Maziah, Mahmood; Abiri, Rambod

2015-01-01

384

[Seafood poisoning in Madagascar: current state of knowledge and results of a retrospective study of the inhabitants of coastal villages].  

PubMed

In 1996 and 1997, a knowledge, attitude and practice survey concerning seafood poisonings was conducted in 560 villages spread along the Madagascar coasts, gathering 585,000 people. 175 serious and 205 mild seafood poisonings after fish, shark and turtle meals occured during the period 1930 to 1996. Squales (mainly Sphyrnidae and Cacharinidae familiesi) are the most often responsible of serious poisoning (48% of episodes), then other fishes (37%), and mainly of the Clupeidae family (herrings, sardinels), then marine turtles (11%), with Eretmochelys imbricata and Chelonia mydas, and finally crabs (4%). Neurological symptoms are predominant in squale poisonings, neurological symptoms associated with gastrointestinal symptoms are present in 50% of all kind of seafood poisoning episods. Most of episods incame on the East Coast (mainly Toamasina and Antisiranana Region) and on the South-West Coast (Toliara Region). Mild seafood poisonings are spread along all the Coasts but central East Coast; fishes are the most often responsible (41% of episodes). Gastro-intestinal symptoms are the most conmon. More than 50% of t interviewed people knows about poisoning risks with some kind of marine animals, but less than 20% practice preventive measures such as giving a piece of fished animal to a domestic animal before eating. These results are used to plan a comprehensive epidemiological surveillance and control programme. PMID:10623871

Ribes, G C; Ramarokoto, S; Rabearintsoa, S; Robinson, R; Ranaivoson, G; Rakotonjanabelo, L A; Rabeson, D

1999-01-01

385

High Prevalence of Hepatitis E in Humans and Pigs and Evidence of Genotype-3 Virus in Swine, Madagascar  

PubMed Central

Hepatitis E virus (HEV) causes an orofecal disease transmitted through poor hygiene environments, contaminated food (mainly pork products), or by contacts with infected animals. Very little data are currently available regarding the disease in the Southwestern Indian Ocean Islands. We report the first sero- and viro-survey for HEV in human and swine in Madagascar. A seroprevalence rate of 14.1% (60 of 427) was measured in slaughterhouse workers. Seroprevalence to HEV in pigs was estimated to 71.2% (178 of 250), strongly suggesting the existence of a zoonotic cycle. Three out of 250 pig livers (1.2%) tested HEV RNA-positive by quantitative polymerase chain reaction. Phylogenetic analyses based on 1-kb sequences of the ORF 2-3 identified these viruses as HEV genotype 3. Sequences clustered in a distinct Malagasy sub-clade, possibly representative of a new sub-genotype, for which the date of emergence was estimated around 1989. Further studies are needed to confirm other transmission routes of HEV to humans, especially through non-zoonotic cycles. PMID:23208879

Temmam, Sarah; Besnard, Lydia; Andriamandimby, Soa Fy; Foray, Coralie; Rasamoelina-Andriamanivo, Harentsoaniaina; Hraud, Jean-Michel; Cardinale, Eric; Dellagi, Koussay; Pavio, Nicole; Pascalis, Herv; Porphyre, Vincent

2013-01-01

386

[Resurgence of the plague in the Ikongo district of Madagascar in 1998. 1. Epidemiological aspects in the human population].  

PubMed

Between the 20th October and the 18th November 1998, an outbreak of bubonic plague was declared in a hamlet in the Ikongo district of Madagascar. We conducted an epidemiological survey because of the re-emergence of the disease in this area (the last cases had been notified in 1965) and because of the low altitude compared to the classical Malagasy foci. The outbreak had been preceded by an important rat epizootics during September. A total of 21 cases were registered with an attack rate of 16.7% (21/126) and a lethality rate of 33% (7/21). The disease was more prevalent in males (66% of cases) and children aged < 15 years, as observed in general throughout the country. The anti-F1 seroprevalence among the contact population was 13.5% (13/96), probably attributable to subclinical infection by Yersinia pestis. No rodent was trapped during the survey, but an endemic hedgehog (Tenrec ecaudatus) was highly seropositive, suggesting a recent transmission of the plague bacillus among this species. The small mammals and vectors possibly involved in these new foci were investigated in May 1999. PMID:11475028

Migliani, R; Ratsitorahina, M; Rahalison, L; Rakotoarivony, I; Duchemin, J B; Duplantier, J M; Rakotonomenjanahary, J; Chanteau, S

2001-05-01

387

Expression patterns of genes involved in the defense and stress response of Spiroplasma citri infected Madagascar Periwinkle Catharanthus roseus.  

PubMed

Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of periwinkle. The response of plants to S. citri infection is very little known at the transcriptome level. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate the expression levels of four selected genes involved in defense and stress responses in naturally and experimentally Spiroplasma citri infected periwinkles. Strictosidine ?-glucosidase involved in terpenoid indole alkaloids (TIAs) biosynthesis pathway showed significant upregulation in experimentally and naturally infected periwinkles. The transcript level of extensin increased in leaves of periwinkles experimentally infected by S. citri in comparison to healthy ones. A similar level of heat shock protein 90 and metallothionein expression was observed in healthy, naturally and experimentally spiroplasma-diseased periwinkles. Overexpression of Strictosidine ?-glucosidase demonstrates the potential utility of this gene as a host biomarker to increase the fidelity of S. citri detection and can also be used in breeding programs to develop stable disease-resistance varieties. PMID:22408455

Nejat, Naghmeh; Vadamalai, Ganesan; Dickinson, Matthew

2012-01-01

388

A 7-Deoxyloganetic Acid Glucosyltransferase Contributes a Key Step in Secologanin Biosynthesis in Madagascar Periwinkle[C][W][OPEN  

PubMed Central

Iridoids form a broad and versatile class of biologically active molecules found in thousands of plant species. In addition to the many hundreds of iridoids occurring in plants, some iridoids, such as secologanin, serve as key building blocks in the biosynthesis of thousands of monoterpene indole alkaloids (MIAs) and many quinoline alkaloids. This study describes the molecular cloning and functional characterization of three iridoid glucosyltransfeases (UDP-SUGAR GLYCOSYLTRANSFERASE6 [UGT6], UGT7, and UGT8) from Madagascar periwinkle (Catharanthus roseus) with remarkably different catalytic efficiencies. Biochemical analyses reveal that UGT8 possessed a high catalytic efficiency toward its exclusive iridoid substrate, 7-deoxyloganetic acid, making it better suited for the biosynthesis of iridoids in periwinkle than the other two iridoid glucosyltransfeases. The role of UGT8 in the fourth to last step in secologanin biosynthesis was confirmed by virus-induced gene silencing in periwinkle plants, which reduced expression of this gene and resulted in a large decline in secologanin and MIA accumulation within silenced plants. Localization studies of UGT8 using a carborundum abrasion method for RNA extraction show that its expression occurs preferentially within periwinkle leaves rather than in epidermal cells, and in situ hybridization studies confirm that UGT8 is preferentially expressed in internal phloem associated parenchyma cells of periwinkle species. PMID:24104568

Asada, Keisuke; Salim, Vonny; Masada-Atsumi, Sayaka; Edmunds, Elizabeth; Nagatoshi, Mai; Terasaka, Kazuyoshi; Mizukami, Hajime; De Luca, Vincenzo

2013-01-01

389

A spatially explicit metapopulation model and cattle trade analysis suggests key determinants for the recurrent circulation of rift valley Fever virus in a pilot area of madagascar highlands.  

PubMed

Rift Valley fever (RVF) is a vector-borne zoonotic disease that causes high morbidity and mortality in ruminants. In 2008-2009, a RVF outbreak affected the whole Madagascar island, including the Anjozorobe district located in Madagascar highlands. An entomological survey showed the absence of Aedes among the potential RVF virus (RVFV) vector species identified in this area, and an overall low abundance of mosquitoes due to unfavorable climatic conditions during winter. No serological nor virological sign of infection was observed in wild terrestrial mammals of the area, suggesting an absence of wild RVF virus (RVFV) reservoir. However, a three years serological and virological follow-up in cattle showed a recurrent RVFV circulation. The objective of this study was to understand the key determinants of this unexpected recurrent transmission. To achieve this goal, a spatial deterministic discrete-time metapopulation model combined with cattle trade network was designed and parameterized to reproduce the local conditions using observational data collected in the area. Three scenarios that could explain the RVFV recurrent circulation in the area were analyzed: (i) RVFV overwintering thanks to a direct transmission between cattle when viraemic cows calve, vectors being absent during the winter, (ii) a low level vector-based circulation during winter thanks to a residual vector population, without direct transmission between cattle, (iii) combination of both above mentioned mechanisms. Multi-model inference methods resulted in a model incorporating both a low level RVFV winter vector-borne transmission and a direct transmission between animals when viraemic cows calve. Predictions satisfactorily reproduced field observations, 84% of cattle infections being attributed to vector-borne transmission, and 16% to direct transmission. These results appeared robust according to the sensitivity analysis. Interweaving between agricultural works in rice fields, seasonality of vector proliferation, and cattle exchange practices could be a key element for understanding RVFV circulation in this area of Madagascar highlands. PMID:25474116

Nicolas, Galle; Chevalier, Vronique; Tantely, Luciano Michal; Fontenille, Didier; Durand, Benot

2014-12-01

390

A Spatially Explicit Metapopulation Model and Cattle Trade Analysis Suggests Key Determinants for the Recurrent Circulation of Rift Valley Fever Virus in a Pilot Area of Madagascar Highlands  

PubMed Central

Rift Valley fever (RVF) is a vector-borne zoonotic disease that causes high morbidity and mortality in ruminants. In 20082009, a RVF outbreak affected the whole Madagascar island, including the Anjozorobe district located in Madagascar highlands. An entomological survey showed the absence of Aedes among the potential RVF virus (RVFV) vector species identified in this area, and an overall low abundance of mosquitoes due to unfavorable climatic conditions during winter. No serological nor virological sign of infection was observed in wild terrestrial mammals of the area, suggesting an absence of wild RVF virus (RVFV) reservoir. However, a three years serological and virological follow-up in cattle showed a recurrent RVFV circulation. The objective of this study was to understand the key determinants of this unexpected recurrent transmission. To achieve this goal, a spatial deterministic discrete-time metapopulation model combined with cattle trade network was designed and parameterized to reproduce the local conditions using observational data collected in the area. Three scenarios that could explain the RVFV recurrent circulation in the area were analyzed: (i) RVFV overwintering thanks to a direct transmission between cattle when viraemic cows calve, vectors being absent during the winter, (ii) a low level vector-based circulation during winter thanks to a residual vector population, without direct transmission between cattle, (iii) combination of both above mentioned mechanisms. Multi-model inference methods resulted in a model incorporating both a low level RVFV winter vector-borne transmission and a direct transmission between animals when viraemic cows calve. Predictions satisfactorily reproduced field observations, 84% of cattle infections being attributed to vector-borne transmission, and 16% to direct transmission. These results appeared robust according to the sensitivity analysis. Interweaving between agricultural works in rice fields, seasonality of vector proliferation, and cattle exchange practices could be a key element for understanding RVFV circulation in this area of Madagascar highlands. PMID:25474116

Nicolas, Galle; Chevalier, Vronique; Tantely, Luciano Michal; Fontenille, Didier; Durand, Benot

2014-01-01

391

A new species of the Boophis rappiodes group (Anura, Mantellidae) from the Sahamalaza Peninsula, northwest Madagascar, with acoustic monitoring of its nocturnal calling activity.  

PubMed

A new species of treefrog of the Boophis rappiodes group (Anura, Mantellidae) is described from the Sahamalaza - Iles Radama National Park in northwest Madagascar. This new species is green in colour with bright red speckling across its head and dorsum; similar in morphology to other species of this group including: B. bottae, B. rappiodes, B. erythrodactylus and B. tasymena. The new species can be distinguished by its advertisement call and by a genetic divergence of more than 4.9% in the analysed mitochondrial 16S rRNA gene fragment. Its call consists of two note types: a trill and a click; although similar sounding to B. bottae, the trill note of the new species has a faster pulse rate while the click note is predominantly two-pulsed rather than three. All individuals were detected from the banks of two streams in Ankarafa Forest. The new species represents the only member of the B. rappiodes group endemic to Madagascar's western coast, with the majority of other members known from the eastern rainforest belt. Despite its conspicuous call, it has not been detected from other surveys of northwest Madagascar and it is likely to be a local endemic to the peninsula. The ranges of two other amphibian species also appear restricted to Sahamalaza, and so the area seems to support a high level of endemicity. Although occurring inside a National Park, this species is highly threatened by the continuing decline in the quality and extent of its habitat. Due to these threats it is proposed that this species should be classified as Critically Endangered according to the IUCN Red List criteria. PMID:25152689

Penny, Samuel G; Andreone, Franco; Crottini, Angelica; Holderied, Marc W; Rakotozafy, Lovasoa Sylviane; Schwitzer, Christoph; Rosa, Gonalo M

2014-01-01

392

Phlebotomine sand flies from Madagascar (Diptera: Psychodidae). VII. An identification key for Phlebotomus with the description of Phlebotomus (Anaphlebotomus) vaomalalae n. sp.  

PubMed Central

An identification key of the Phlebotomus in Madagascar is proposed as well as the description of the male and female Phlebotomus (Anaphlebotomus) vaomalalae n. sp. from Mikea Forest in the south-west of Madagascar. The assignation of this new species to the genus Phlebotomus is based on the presence of mesanepisternal setae. Its inclusion in the subgenus Anaphlebotomus is based on the males on the presence of four spines on the style, the lack of a coxite basal process and the existence of a bifurcated paramere. The female has cibarial and pharyngeal armature and spermathecal architecture similar to Phlebotomus fertei and Phlebotomus berentiensis, two other Malagasy species which belong to Anaphlebotomus. Male and female are held to belong to the same species because of their morphological characters, the homology (100%) of their partial cytochrome b mtDNA sequences and their capture in the same trap. P. vaomalalae n. sp. is a small species compared to the other Phlebotomus species of Madagascar. The cibarium of the male and the female of P. vaomalalae n. sp. is armed with teeth, like those of other Malagasy Phlebotomus. However, it differs in the arrangement and shape of the respective teeth and denticles. The male of P. vaomalalae n. sp. looks like that of P. fontenillei due to its tuft of coxal setae (lacking in P. berentiensis and P. fertei) but differs from this species by the location of this tuft. As P. fertei and P. berentiensis, there is no spermathecal common duct in P. vaomalalae n. sp. PMID:23419267

Randrianambinintsoa, Fano Jos; Lger, Nicole; Robert, Vincent; Depaquit, Jrme

2013-01-01

393

Field evaluation of an immunoglobulin G anti-F1 enzyme-linked immunosorbent assay for serodiagnosis of human plague in Madagascar.  

PubMed

Bacteriological isolation of Yersinia pestis is the reference test for confirming plague infection, but recovery of the pathogen from human samples is usually very poor. When the etiology of the disease cannot be bacteriologically confirmed, it may be useful to possess alternative tests such as detection of specific circulating antibodies to help guide the diagnosis. In the present study, the immunoglobulin G (IgG) anti-F1 enzyme-linked immunosorbent assay (ELISA) has been applied to various human sera to evaluate its large-scale applicability in the high-endemicity plague foci of Madagascar. The sensitivity of the test was found to be 91.4%, and its specificity was 98.5%. The positive and negative predictive values were 96 and 96.6%, respectively. Seroconversion was observed on day 7 after onset of the disease. Patients with a positive ELISA result could be separated into high (82%) and low (18%) IgG anti-F1 responders. Cross-reactions with eight other infectious diseases prevalent in Madagascar were scarce and were found in 1 of 27 Mycobacterium tuberculosis-, 3 of 34 Schistosoma haematobium-, and 1 of 41 Salmonella-infected patients. Finally, the efficiency of the IgG anti-F1 ELISA was evaluated during the Mahajanga, Madagascar, plague outbreak of 1995. When the number of ELISA-positive patients was added to the number of bacteriologically confirmed and probable cases, the number of positive patients was increased by 35%. In conclusion, although it does not replace bacteriology, IgG anti-F1 ELISA is a useful and powerful tool for retrospective diagnosis and epidemiological surveillance of plague outbreaks. PMID:9302210

Rasoamanana, B; Leroy, F; Boisier, P; Rasolomaharo, M; Buchy, P; Carniel, E; Chanteau, S

1997-09-01

394

Ammonite and inoceramid biostratigraphy and biogeography of the Cenomanian through basal Middle Campanian (Upper Cretaceous) of the Morondava Basin, western Madagascar  

NASA Astrophysics Data System (ADS)

The stratigraphic distribution of ammonite and inoceramid faunas of the richly fossiliferous Cenomanian through basal Middle Campanian (Upper Cretaceous) succession of the Morondava Basin, western Madagascar, is provided, and biozonations, based on both groups, are established. The correlation with former schemes is discussed and the chronostratigraphic potential of each of the groups is evaluated, with reference to their biogeographic affinities. The study is based on entirely new field collections at four sections in the central and southern part of the Morondava Basin: (1) Antsirasira-Ampolipoly, (2) Mahaboboka, (3) Vohipaly, and (4) Manasoa-on-Onilahy. Geological logs and field details of these sections are also provided.

Walaszczyk, Ireneusz; James Kennedy, William; Dembicz, Krzysztof; Gale, Andrew S.; Praszkier, Tomasz; Rasoamiaramanana, Armand H.; Randrianaly, Hasina

2014-01-01

395

Effects of forest structure and composition on food availability for Varecia variegata at Ranomafana National Park, Madagascar.  

PubMed

We present a summary of a long-term field study that examined the effects of forest disturbance on the availability of palatable fruit and its utilization by V. variegata. Forest structure and tree species composition were measured in three adjacent study areas, with different histories of disturbance, in Ranomafana National Park (RNP), Madagascar. V. variegata abundance was monitored by frequent encounters with resident groups and periodic censuses conducted along trails. Finally, the abundance of mature fruit in species used by V. variegata was scored monthly at representative trees at several locations. V. variegata abundance was most consistent in the least anthropogenically disturbed site, while no established lemur groups were observed in the heavily logged site for over a decade post-harvest. Lemur abundance was variable in the selectively logged site. The presence of select food trees, particularly specimens with voluminous crowns capable of producing abundant fruit crops, appears to be key to the establishment and expansion of V. variegata groups. Our analysis of year-long fruit utilization revealed a high degree of preference for several species of trees. Two species exhibited mature fruit in a low percentage of stems but were available for a protracted period of time, while two additional species showed high intraspecific fruiting synchrony and were available for a shorter period of time. These contrasting phenologies, rather than the individual tree species, may be most important to V. variegata due to their coincident timing of fruit maturation with key lemur life-history events. Any disturbance-natural or anthropogenic-that disrupts the phenology cycles of food trees has the potential to impact lemur abundance and dispersion. Intense disturbances, such as heavy logging or severe cyclones, have long-lasting impacts on fruit production, while selective logging or moderate cyclonic windthrow cause more transient impacts. V. variegata is adapted to deal with an intrinsically erratic food supply by virtue of its reproductive biology and social behavior. PMID:15898066

Balko, Elizabeth A; Underwood, H Brian

2005-05-01

396

Does female dominance facilitate feeding priority in black-and-white ruffed lemurs (Varecia variegata) in southeastern Madagascar?  

PubMed

Although many Malagasy lemurs are thought to be female dominant and to have female feeding priority, to date the relationship between these behaviors has been rigorously established only in Lemur catta, and other ways that females might achieve feeding priority have not been examined closely. Erhart and Overdorff [International Journal of Primatology 20:927-940, 1999] suggested that one way female primates achieve feeding priority is to initiate and lead groups to food, thereby gaining access to the food first and positively influencing their food intake compared to other group members. Here we describe female dominance patterns and potential measures of feeding priority in two groups of black-and-white ruffed lemurs (Varecia variegata) that were observed over a 15-month period in southeastern Madagascar. We predicted that the females would 1) be consistently dominant to males, 2) lead groups to food sources more often than males, and 3) have higher feeding rates compared to males when they arrived at food sources first. The results were dissimilar between the study groups. During the study, the oldest adult female in group 1 died. There was no evidence for female dominance in this group, and the remaining (likely natal) female did not lead the group more often, nor did she have a higher food intake than males. Group 1 dispersed shortly after the time frame reported here. In contrast, the resident female in group 2 was dominant to group males (based on agonistic interactions), led the group to food sources more often, and experienced a higher food intake when she arrived first at a food source. How these patterns vary over time and are influenced by the number of females in groups, group stability, food quality, and reproductive condition will be examined in future analyses. PMID:15898069

Overdorff, Deborah J; Erhart, Elizabeth M; Mutschler, Thomas

2005-05-01

397

Effects of forest structure and composition on food availability for Varecia variegata at Ranomafana National Park, Madagascar  

USGS Publications Warehouse

We present a summary of a long-term field study that examined the effects of forest disturbance on the availability of palatable fruit and its utilization by V. variegata. Forest structure and tree species composition were measured in three adjacent study areas, with different histories of disturbance, in Ranomafana National Park (RNP), Madagascar. V. variegata abundance was monitored by frequent encounters with resident groups and periodic censuses conducted along trails. Finally, the abundance of mature fruit in species used by V. variegata was scored monthly at representative trees at several locations. V. variegata abundance was most consistent in the least anthropogenically disturbed site, while no established lemur groups were observed in the heavily logged site for over a decade post-harvest. Lemur abundance was variable in the selectively logged site. The presence of select food trees, particularly specimens with voluminous crowns capable of producing abundant fruit crops, appears to be key to the establishment and expansion of V variegata groups. Our analysis of year-long fruit utilization revealed a high degree of preference for several species of trees. Two species exhibited mature fruit in a low percentage of stems but were available for a protracted period of time, while two additional species showed high intraspecific fruiting synchrony and were available for a shorter period of time. These contrasting phenologies, rather than the individual tree species, may be most important to V. variegata due to their coincident timing of fruit maturation with key lemur life-history events. Any disturbance-natural or anthropogenic-that disrupts the phenology cycles of food trees has the potential to impact lemur abundance and dispersion. Intense disturbances, such as heavy logging or severe cyclones, have long-lasting impacts on fruit production, while selective logging or moderate cyclonic windthrow cause more transient impacts. V. variegata is adapted to deal with an intrinsically erratic food supply by virtue of its reproductive biology and social behavior.

Balko, E.A.; Underwood, H.B.

2005-01-01

398

Sex determination in Madagascar geckos of the genus Paroedura (Squamata: Gekkonidae): are differentiated sex chromosomes indeed so evolutionary stable?  

PubMed

Among amniote vertebrates, geckos represent a clade with exceptional variability in sex determination; however, only a minority of species of this highly diverse group has been studied in this respect. Here, we describe for the first time a female heterogamety in the genus Paroedura, the group radiated in Madagascar and adjacent islands. We identified homomorphic ZZ/ZW sex chromosomes with a highly heterochromatic W chromosome in Paroedura masobe, Paroedura oviceps, Paroedura karstophila, Paroedura stumpffi, and Paroedura lohatsara. Comparative genomic hybridization (CGH) revealed that female-specific sequences are greatly amplified in the W chromosome of P. lohatsara and that P. gracilis seems to possess a derived system of multiple sex chromosomes. Contrastingly, neither CGH nor heterochromatin visualization revealed differentiated sex chromosomes in the members of the Paroedura picta-Paroedura bastardi-Paroedura ibityensis clade, which is phylogenetically nested within lineages with a heterochromatic W chromosome. As a sex ratio consistent with genotypic sex determination has been reported in P. picta, it appears that the members of the P. picta-P. bastardi-P. ibityensis clade possess homomorphic, poorly differentiated sex chromosomes and may represent a rare example of evolutionary loss of highly differentiated sex chromosomes. Fluorescent in situ hybridization (FISH) with a telomeric probe revealed a telomere-typical pattern in all species and an accumulation of telomeric sequences in the centromeric region of autosomes in P. stumpffi and P. bastardi. Our study adds important information for the greater understanding of the variability and evolution of sex determination in geckos and demonstrates how the geckos of the genus Paroedura provide an interesting model for studying the evolution of the sex chromosomes. PMID:25056523

Koubov, Martina; Johnson Pokorn, Martina; Rovatsos, Michail; Farka?ov, Klra; Altmanov, Marie; Kratochvl, Luk

2014-12-01

399

The possibility of using photogrammetric and remote sensing techniques to model lavaka (gully erosion) development in Madagascar  

NASA Astrophysics Data System (ADS)

Gully erosion is a worldwide problem for it has a number of undesirable effects and their development is hard to follow. Madagascar is one of the most affected countries for its highlands are densely covered with gullies named lavakas. Lavaka formation and development seems to be triggered by many regional and local causes but the actual reasons are still poorly understood. Furthermore lavakas differ from normal gullies due to their enormous size and special shape. Field surveys are time consuming and data from two-dimensional measurements and pictures (even aerial) might lack major information for morphologic studies. Therefore close range surveying technologies should be used to get three-dimensional information about these unusual and complex features. This contribution discusses which remote sensing and photogrammetric techniques are adequate to survey the development of lavakas, their volume change and sediment budget. Depending on the types and properties (such as volume, depth, shape, vegetation) of the lavaka different methods will be proposed showing pros and cons of each one of them. Our goal is to review techniques to model, survey and analyze lavakas development to better understand the cause of their formation, special size and shape. Different methods are evaluated and compared from field survey through data processing, analyzing cost-effectiveness, potential errors and accuracy for each one of them. For this purpose we will also consider time- and cost-effectiveness of the softwares able to render the images into 3D model as well as the resolution and accuracy of the outputs. Further studies will concentrate on using the three dimensional models of lavakas which will be later on used for geomorphological studies in order to understand their special shape and size. This is ILARG-contribution #07.

Raveloson, Andrea; Szkely, Balzs; Molnr, Gbor; Rasztovits, Sascha

2013-04-01

400

Assessing Natural Resource Use by Forest-Reliant Communities in Madagascar Using Functional Diversity and Functional Redundancy Metrics  

PubMed Central

Biodiversity plays an integral role in the livelihoods of subsistence-based forest-dwelling communities and as a consequence it is increasingly important to develop quantitative approaches that capture not only changes in taxonomic diversity, but also variation in natural resources and provisioning services. We apply a functional diversity metric originally developed for addressing questions in community ecology to assess utilitarian diversity of 56 forest plots in Madagascar. The use categories for utilitarian plants were determined using expert knowledge and household questionnaires. We used a null model approach to examine the utilitarian (functional) diversity and utilitarian redundancy present within ecological communities. Additionally, variables that might influence fluctuations in utilitarian diversity and redundancyspecifically number of felled trees, number of trails, basal area, canopy height, elevation, distance from villagewere analyzed using Generalized Linear Models (GLMs). Eighteen of the 56 plots showed utilitarian diversity values significantly higher than expected. This result indicates that these habitats exhibited a low degree of utilitarian redundancy and were therefore comprised of plants with relatively distinct utilitarian properties. One implication of this finding is that minor losses in species richness may result in reductions in utilitarian diversity and redundancy, which may limit local residents' ability to switch between alternative choices. The GLM analysis showed that the most predictive model included basal area, canopy height and distance from village, which suggests that variation in utilitarian redundancy may be a result of local residents harvesting resources from the protected area. Our approach permits an assessment of the diversity of provisioning services available to local communities, offering unique insights that would not be possible using traditional taxonomic diversity measures. These analyses introduce another tool available to conservation biologists for assessing how future losses in biodiversity will lead to a reduction in natural resources and provisioning services from forests. PMID:21909413

Brown, Kerry A.; Flynn, Dan F. B.; Abram, Nicola K.; Ingram, J. Carter; Johnson, Steig E.; Wright, Patricia

2011-01-01

401

On the active principles of the Euphorbiaceae, XII. Highly unsaturated irritant diterpene esters from Euphorbia tirucalli originating from Madagascar.  

PubMed

The latex of Euphorbia tirucalli originating from Madagascar contains as irritant constituents ingenane- and tigliane-type diterpene esters derived from the parent alcohols ingenol and phorbol. The main irritant constituents are isomeric 12,13-acetates, acylates of phorbol as well as 3-acylates of ingenol. As acyl groups, they carry homologous, highly unsaturated aliphatic acids of the general structure CH3-(CH2)m-(CH = CH)n-COOH (m = 2,4; n = 2,3,4,5; total number N of C-atoms = 2n + m + 2). The lack of 4-deoxyphorbol esters in this latex as compared to latex of South African origin is probably indicative of the existence of chemical races of E. tirucalli. In the acyl moiety of phorbol esters investigated in detail, an increasing number of C-atoms or an increasing number of double bonds at a fixed number of C-atoms leads to an increase of irritant activity. As compared to their saturated analogs, corresponding unsaturated phorbol esters exhibit similar irritant activities. On the other hand, by an increasing number of conjugated double bonds in the acyl moieties of phorbol esters, the promoting activity is decreased, thus indicating that irritant activity is a necessary, but insufficient, requirement for promoting activity of phorbol esters. An assessment of a potential carcinogenic risk involved in mass production and handling of the plant should point to the very weak tumor-promoting activity and the chemical instability demonstrated for the diterpene constituents in the latex and hence in all plant parts. PMID:3760879

Frstenberger, G; Hecker, E

1986-01-01

402

First direct evidence of hibernation in an eastern dwarf lemur species ( Cheirogaleus crossleyi) from the high-altitude forest of Tsinjoarivo, central-eastern Madagascar  

NASA Astrophysics Data System (ADS)

The nocturnal dwarf lemurs of Madagascar (genus Cheirogaleus) are the only primates known to be obligate hibernators. Although the physiology of hibernation has been studied widely in the western, small-bodied species, Cheirogaleus medius, no direct evidence of hibernation, i.e., body temperature recordings, has been reported for any of the three recognized eastern dwarf lemur species. We present skin temperature data collected by external collar transmitters from two eastern dwarf lemur individuals ( Cheirogaleus crossleyi) captured in the high-altitude forest of Tsinjoarivo, central-eastern Madagascar. Our study species is larger in body size than western dwarf lemurs and inhabits much colder environments. We present the first evidence of hibernation in an eastern dwarf lemur species, and we compare the results with data available for the western species. Although the hibernation period is shorter in dwarf lemurs from Tsinjoarivo, minimum body temperatures are lower than those reported for C. medius. Both individuals at Tsinjoarivo showed limited passive and extended deep hibernation during which they did not track ambient temperature as observed in most western dwarf lemurs. Because ambient temperatures at Tsinjoarivo never exceed 30C, dwarf lemurs have to experience arousals to maintain homeostasis during periods of hibernation. We show that large dwarf lemurs (>400 g) are capable of undergoing deep hibernation and suggest that cold, high-altitude forests may render hibernation highly advantageous during periods of food scarcity. This study has implications for understanding the physiology of hibernation in small-bodied lemurs.

Blanco, Marina B.; Rahalinarivo, Vololonirina

2010-10-01

403

A new geological framework for south-central Madagascar, and its relevance to the "out-of-Africa" hypothesis  

USGS Publications Warehouse

The Precambrian shield of south-central Madagascar, excluding the Vohibory region, consists of three geologic domains, from north to south: Antananarivo, Ikalamavony-Itremo, and Anosyen-Androyen. The northern Antananarivo domain represents the Neoarchean sector of the Greater Dharwar Craton amalgamated at 2.52-2.48. Ga. The Greater Dharwar Craton is overlain by several groups of Meso- to Neoproterozoic supracrustal rocks (Ambatolampy, Manampotsy, Ampasary, Sahantaha, and Maha Groups) each with a common and diagnostic signature of Paleoproterozoic detrital zircons (2.2-1.8. Ga). The central domain (Ikalamavony-Itremo) consists of two distinct parts. The Itremo Sub-domain, in the east, is a structurally intercalated sequence of Neoarchean gneiss and shallow marine metasedimentary rocks of Paleo-Mesoproterozoic age (Itremo Group), the latter with Paleoproterozoic detrital zircons ranging in age between 2.2 and 1.8. Ga. The Ikalamavony Sub-domain, to the west, contains abundant volcano-clastic metasediments and lesser quartzite (Ikalamavony Group), formed between 1.03. Ga and 0.98. Ga, and intruded by igneous rocks (Dabolava Suite) of Stenian-Tonian age. Structurally intercalated with these are sheets of Neoarchean gneiss (~2.5. Ga) and Neoproterozoic metaclastic rocks (Molo Group). Like the Itremo Group, quartzite of the Ikalamavony Group has detrital zircons of Paleoproterozoic age (2.1-1.8. Ga). The southern domain of Anosyen-Androyen consists of a newly recognized suite of Paleoproterozoic igneous rocks (2.0-1.8. Ga), and stratified supracrustal rocks also having Paleoproterozoic detrital zircons (2.3-1.8. Ga). The contact between the Anosyen-Androyen and Ikalamavony-Itremo domains, formerly known as the Ranotsara-Bongolava shear zone, is a tightly folded and highly flattened boundary that was ductilely deformed in Ediacaran time. It is roughly equivalent to the Palghat-Cauvery shear zone in south India, and it defines approximately the boundary between the Archean Greater Dharwar Craton (to the north) and the Paleoproterozoic terrane of Anosyen-Androyen (to the south).

Tucker, R.D.; Roig, J.Y.; Macey, P.H.; Delor, C.; Amelin, Y.; Armstrong, R.A.; Rabarimanana, M.H.; Ralison, A.V.

2011-01-01

404

Molecular characterization of multidrug-resistant extended-spectrum ?-lactamase-producing Enterobacteriaceae isolated in Antananarivo, Madagascar  

PubMed Central

Background We investigated the molecular characteristics of multidrug-resistant, extended-spectrum ?-lactamase (ESBL)-producing Enterobacteriaceae isolated in community settings and in hospitals in Antananarivo, Madagascar. Results Forty-nine E. coli, K. pneumoniae, K. oxytoca and E. cloacae ESBL-producing isolates were studied. In antimicrobial susceptibility analyses, many of the isolates exhibited resistance to aminoglycosides, fluoroquinolones and trimethoprim-sulfamethoxazole. Gene amplification analysis and sequencing revealed that 75.5% (n=37) of the isolates harbored blaCTX-M-15 and 38.7% (n=19) harbored blaSHV-12. The non-ESBLs resistance genes detected were blaTEM-1, blaOXA-1, aac(6?)-Ib,aac(6?)-Ib-cr, tetA, sul-1, sul-2, qnrA, qnrB and catB-3. We found dfrA and aadA gene cassettes in the class 1 integron variable regions of the isolates, and the combination of dfrA17-aadA5 to be the most prevalent. All blaCTX-M-15 positive isolates also contained the ISEcp1 insertion element. Conjugation and transformation experiments indicated that 70.3% of the antibiotic resistance genes resided on plasmids. Through a PCR based replicon typing method, plasmids carrying the blaSHV-12 or blaCTX-M-15 genes were assigned to either the IncFII replicon type or, rarely, to the HI2 replicon type. All isolates were subtyped by the rep-PCR and ERIC-PCR methods. Phylogenetic grouping and virulence genotyping of the E. coli isolates revealed that most of them belonged to group A1. One isolate assigned to group B2 harbored blaCTX-M-15 and five virulence genes (traT, fyuA, iutA, iha and sfa) and was related to the O25b-ST131 clone. Conclusions Our results highlight the dissemination of multidrug resistant Enterobacteriaceae isolates in Antananarivo. These findings underline the need for a rational use of antibiotic and for appropriate methods of screening ESBL in routine laboratories in Antananarivo. PMID:23594374

2013-01-01

405

Unusual evolution of silica-under- and -oversaturated alkaline rocks in the Cenozoic Ambohimirahavavy Complex (Madagascar): Mineralogical and geochemical evidence  

NASA Astrophysics Data System (ADS)

The almost unknown Ambohimirahavavy ring complex in the Cenozoic alkaline province of northwestern Madagascar has recently attracted considerable interest because of the discovery of important rare-metal mineralization. The complex consists of arc-shaped bodies made up of silica-under- and -oversaturated syenites and extremely evolved peralkaline granitic dykes, as well as several mafic to felsic volcanic units, including basalt, phonolite and trachyte, all of which have an alkaline affinity. Uranium-lead zircon ages of 24.2 0.6 Ma and 23.5 6.8 Ma have been obtained for nepheline syenites and peralkaline granitic dykes, respectively, which, together with field data and ages of neighboring complexes, support emplacement controlled by regional lithospheric structures, rather than an evolving hot spot. Whole-rock major and trace-element and Sr-Nd isotopic data for the mafic suite suggest that the parental melt of this complex was generated by low degrees of melting of a metasomatized mantle source with residual amphibole. Fractional crystallization of this alkali basaltic melt likely produced the silica-undersaturated suite. We propose that the silica-oversaturated suite evolved from the undersaturated melt after contamination of the latter by crustal material. Further evolution to peralkaline compositions in both suites is attributed mainly to plagioclase and alkali feldspar segregation. Nepheline and feldspar compositions, as well as considerations of mineral equilibria among mafic silicates and Fe-Ti oxide minerals indicate crystallization temperatures of 1000 to 700 C and an oxygen fugacity of 0.4 to 0.8 log units below the fayalite-magnetite-quartz (FMQ) buffer at 1 kbar for the silica-undersaturated melt, and temperatures of 860 to 570 C and an oxygen fugacity of 1.5 to 3.8 log units below FMQ for the oversaturated syenitic melt. The undersaturated melt evolved towards a more peralkaline composition. Crystallization of arfvedsonite plus aegirine further reduced the melt the evolution of which ended with fluid exsolution. At late stages of crystallization, the oversaturated melt departed from the reducing trend of the undersaturated melt, evolving towards high oxygen fugacity. Very late exsolution of the fluid permitted concentration of the HFSE in the last stages of magmatic evolution with local production of low-temperature pegmatitic phases extremely enriched in these elements.

Estrade, Guillaume; Bziat, Didier; Salvi, Stefano; Tiepolo, Massimo; Paquette, Jean-Louis; Rakotovao, Soatsitohaina

2014-10-01

406

Viral and Atypical Bacterial Etiology of Acute Respiratory Infections in Children under 5 Years Old Living in a Rural Tropical Area of Madagascar  

PubMed Central

Background In Madagascar, very little is known about the etiology and prevalence of acute respiratory infections (ARIs) in a rural tropical area. Recent data are needed to determine the viral and atypical bacterial etiologies in children with defined clinical manifestations of ARIs. Methods During one year, we conducted a prospective study on ARIs in children between 2 to 59 months in the community hospital of Ampasimanjeva, located in the south-east of Madagascar. Respiratory samples were analyzed by multiplex real-time RT-PCR, including 18 viruses and 2 atypical bacteria. The various episodes of ARI were grouped into four clinical manifestations with well-documented diagnosis: Community Acquired Pneumonia(CAP, group I), Other acute lower respiratory infections (Other ALRIs, group II), Upper respiratory tract infections with cough (URTIs with cough, group III)and Upper respiratory tract infections without cough (URTIs without cough, group IV). Results 295 children were included in the study between February 2010 and February 2011. Viruses and/or atypical bacteria respiratory pathogens were detected in 74.6% of samples, the rate of co-infection was 27.3%. Human rhinovirus (HRV; 20.5%), metapneumovirus (HMPV A/B, 13.8%), coronaviruses (HCoV, 12.5%), parainfluenza virus (HPIV, 11.8%) and respiratory syncytial virus A and B (RSV A/B, 11.8%) were the most detected. HRV was predominantly single detected (23.8%) in all the clinical groups while HMPV A/B (23.9%) was mainly related to CAP (group I), HPIV (17.3%) to the Other ALRIs (group II), RSV A/B (19.5%) predominated in the group URTIs with cough (group III) and Adenovirus (HAdV, 17.8%) was mainly detected in the without cough (group IV). Interpretation This study describes for the first time the etiology of respiratory infections in febrile children under 5 years in a malaria rural area of Madagascar and highlights the role of respiratory viruses in a well clinically defined population of ARIs. PMID:22912897

Hoffmann, Jonathan; Rabezanahary, Henintsoa; Randriamarotia, Martin; Ratsimbasoa, Arsne; Najjar, Josette; Vernet, Guy; Contamin, Bndicte; Paranhos-Baccal, Glucia

2012-01-01

407

Diet and feeding behaviour of the black-and-white ruffed lemur (Varecia variegata variegata) in the Betampona Reserve, eastern Madagascar.  

PubMed

The feeding behaviour and diet of the black-and-white ruffed lemur (Varecia variegata variegata) was investigated in the Betampona Reserve, eastern Madagascar. The highly frugivorous diet of this subspecies was confirmed - feeding on fruits accounting for 92.0% of feeding records. Most feeding at Betampona was observed at 10-25 m above the forest floor amongst flexible, small (0.5-5.0 cm diameter) and oblique/horizontal (0-45 degrees ) supports. The Varecia spent on average 21.7% (+/- 1.5) of their daily activity budget feeding and employ a variety of postures that enable them to harvest fruits in the rain forest canopy. The suspensory postures were the most important in allowing Varecia to compete with other smaller-bodied frugivores. PMID:10828690

Britt, A

2000-01-01

408

Discovery of Sympatric Dwarf Lemur Species in the High-Altitude Rain Forest of Tsinjoarivo, Eastern Madagascar: Implications for Biogeography and Conservation  

PubMed Central

The number of species within the Malagasy lemur genus Cheirogaleus is currently under debate. Museum collections are spotty, and field work, supplemented by morphometric and genetic analysis, is essential for documenting geographic distributions, ecological characteristics and species boundaries. We report here field evidence for 2 dwarf lemur species at Tsinjoarivo, an eastern-central high-altitude rain forest: one, from a forest fragment, displaying coat and dental characteristics similar to C. sibreei (previously described only from museum specimens) and the other, from the continuous forest, resembling individuals of Cheirogaleus found today at Ranomafana National Park, further to the south. This study represents the first confirmation of a living population of grey-fawn, C.-sibreei-like, dwarf lemurs in Madagascar. PMID:19023214

Blanco, Marina B.; Godfrey, Laurie R.; Rakotondratsima, Mamihasimbola; Rahalinarivo, Vololonirina; Samonds, Karen E.; Raharison, Jean-Luc; Irwin, Mitchell T.

2009-01-01

409

But Then He Became My Sipa: The Implications of Relationship Fluidity for Condom Use Among Women Sex Workers in Antananarivo, Madagascar  

PubMed Central

Increasing evidence indicates that sex workers use condoms less consistently with regular (i.e., nonpaying) partners than with clients. Few studies have examined the extent to which these 2 categories are mutually exclusive. In an ethnographic study of women's sex work in Antananarivo, Madagascar, we examined how the meaning of women sex workers sexual relationships could shift among 3 different forms of sex work. Condom use was less likely in forms in which the distinction between client and lover (sipa in Malagasy) was fluid. For many sex workers, therefore, relationships they understood to be intimate imparted the greatest health vulnerability. It is important to examine the influence of the meaning of sexual relationships on condom use for HIV prevention. Policy implications for HIV prevention work with sex workers are considered. PMID:19299685

Hindin, Michelle J.; Nathanson, Constance A.; Rakotoarison, Paul Ghislain; Razafintsalama, Violette

2009-01-01

410

Nuclear factors GT1 and 3AF1 interact with multiple sequences within the promoter of the Tdc gene from Madagascar periwinkle: GT1 is involved in UV light-induced expression  

Microsoft Academic Search

Plant secondary metabolites of the terpenoid indole alkaloid (TIA) class comprise several compounds with pharmaceutical applications.\\u000a A key step in the TIA biosynthetic pathway is catalysed by the enzyme tryptophan decarboxylase (TDC), which channels the primary\\u000a metabolite tryptophan into TIA metabolism. In Catharanthus roseus (Madagascar periwinkle), the Tdc gene is expressed throughout plant development. Moreover, Tdc gene expression is induced

P. B. F. Ouwerkerk; T. O. Trimborn; F. Hilliou; J. Memelink

1999-01-01

411

Aspect Epidemiologique des Sequelles de Brulures a Marrakech, Maroc, a Travers Deux Observations  

PubMed Central

Summary La brlure est un accident qui reste toujours trs frquent au Maroc, ce qui fait d'elle un problme de la sant publique. Les brlures, quand elles sont graves ou profondes, entranent de faon quasi inluctable des squelles fonctionnelles et esthtiques. A travers deux observations de deux enfants prsentant des squelles de brlures graves, ayant retenti pjorativement sur leurs scolarits, on a essay de mettre en vidence quelques facteurs incrimins dans cette tragdie (feu, petites bouteilles de gaz et le manque d'infrastructure, du personnel mdical et paramdical, du matriel ainsi que de la prvention) comme tant une grande cause dans la survenue de ces squelles. Le but de notre travail est d'numrer ces diffrents facteurs intriqus, ainsi que de proposer quelques solutions, tout en insistant sur la prvention. PMID:21991156

Ettalbi, S.; Ibnouzahir, M.; Droussi, H.; Wahbi, S.; Bahaichar, N.; Boukind, E.H.

2009-01-01

412

APPORT DU DECOUPAGE INFRA-COMMUNAL EN IRIS DANS LA SURVEILLANCE EPIDEMIOLOGIQUE DU CANCER DU POUMON  

Microsoft Academic Search

RESUME : La ralisation d'un Atlas du cancer dans l'agglomration grenobloise avait permis de rvler des disparits de rpartition spatiale de l'incidence du cancer du poumon masculin l'chelle communale. L'objectif de ce travail tait donc d'utiliser une nouvelle chelle spatiale d'analyse (l'IRIS) pour dterminer si les disparits observes ne cachaient pas des disparits infra-communales passes inaperues. Des excdents et

Alexandra Senkowski; Marc Colonna; Dominique Bicout

413

Petrogenesis of high-K metagranites in the Kerala Khondalite Belt, southern India: a possible magmatic-arc link between India, Sri Lanka, and Madagascar  

NASA Astrophysics Data System (ADS)

The Proterozoic Kerala Khondalite Belt (KKB), southern India preserves a distinct high-grade terrain that is interpreted to have been situated adjacent to Madagascar and Sri Lanka during Gondwana assembly. As such, it has become a major focus for testing models of supercontinent amalgamation and dispersal. The lithounits of KKB have remarkable petrological similarities to the Highland Complex (HC) of Sri Lanka and south-central Madagascar. However, there is no well-constrained petrogenetic model for the KKB that fits explicitly within a supercontinent reconstruction model. We present here results from our on-going studies on the origin and evolution of K-rich (potassic, where K2O/Na2O > 1) gneisses of KKB in relation to Proterozoic supercontinent events. Our results show, in a major departure from earlier metasedimentary origin, that potassic gneisses are metamorphosed granitoids. The metagranitoid samples display high K2O contents and low Al2O3/(FeO + MgO + TiO2) values. They are moderate to strongly peraluminous (ASI values ranging from 1.05 to 1.47) rocks showing mineralogical, petrological, and geochemical characteristics distinctive of the high-K calc-alkaline suites. Typical of igneous suites, the high-K metagranites show minor variation in chemical compositions with most oxides showing negative correlation with SiO2. Geochemistry illustrates distinctive features of arc-related magmas with LILE (K, Rb, and Th) and LREE enriched patterns and considerable depletion of HSFE (Nb, Zr, and Ti). The high-K metagranites are further characterized by strong negative anomalies of Eu (Eu/Eu* = 0.10-0.44) and Sr, suggesting melting in plagioclase stability field and retention of plagioclase in the residual phase. Petrogenetic discrimination for granitoids, using major and trace elements demonstrates that the high-K metagranites of the KKB formed by partial melting of igneous source in lower- to middle-crust levels. Overall the geochemical features are supportive of origin in relation to a convergent margin setting, possibly in a continental magmatic arc system, which can be connected to the amalgamation and dispersal of continental fragments in a supercontinent event. This study, therefore, provides a lead towards more robust comparisons between the Proterozoic supercontinent events and processes.

Sreejith, C.; Ravindra Kumar, G. R.

2013-01-01

414

The Colposcopic Atlas of Schistosomiasis in the Lower Female Genital Tract Based on Studies in Malawi, Zimbabwe, Madagascar and South Africa  

PubMed Central

Background Schistosoma (S.) haematobium is a neglected tropical disease which may affect any part of the genital tract in women. Female genital schistosomiasis (FGS) may cause abnormal vaginal discharge, contact bleeding, genital tumours, ectopic pregnancies and increased susceptibility to HIV. Symptoms may mimic those typical of sexually transmitted infections (STIs) and women with genital schistosomiasis may be incorrectly diagnosed. An expert consensus meeting suggested that the following findings by visual inspection should serve as proxy indicators for the diagnosis of schistosomiasis of the lower genital tract in women from S. haematobium endemic areas: sandy patches appearing as (1) single or clustered grains or (2) sandy patches appearing as homogenous, yellow areas, or (3) rubbery papules. In this atlas we aim to provide an overview of the genital mucosal manifestations of schistosomiasis in women. Methodology/Principal findings Photocolposcopic images were captured from women, between 1994 and 2012 in four different study sites endemic for S. haematobium in Malawi, Zimbabwe, South Africa and Madagascar. Images and specimens were sampled from sexually active women between 15 and 49 years of age. Colposcopic images of other diseases are included for differential diagnostic purposes. Significance This is the first atlas to present the clinical manifestations of schistosomiasis in the lower female genital tract. It will be freely available for online use, downloadable as a presentation and for print. It could be used for training purposes, further research, and in clinical practice. PMID:25412334

Norseth, Hanne M.; Ndhlovu, Patricia D.; Kleppa, Elisabeth; Randrianasolo, Bodo S.; Jourdan, Peter M.; Roald, Borghild; Holmen, Sigve D.; Gundersen, Svein G.; Bagratee, Jayanthilall; Onsrud, Mathias; Kjetland, Eyrun F.

2014-01-01

415

Studying the nutritional beliefs and food practices of Malagasy school children parents. A contribution to the understanding of malnutrition in Madagascar.  

PubMed

Madagascar is severely affected by the problem of children malnutrition. The present study aimed at exploring school children Malagasy parents' food practices and beliefs structures about the nutritional value of foods, to better understand the causes of this malnutrition. A combination of Focus Groups (72 participants), and questionnaires (1000 interviewees) was used to evaluate the food beliefs and the nutritional habits of low income parents of school age children in urban and rural areas of Antananarivo and Antsiranana. The respondents' beliefs were shown to focus not only on the nutrient and energetic composition of food, but also to involve more general relations between food and health and particularly the sanitary properties of food. Compared with such sanitary properties, nutrient content was not considered to be the priority in food choice and food preparation. The food category considered to be the most nutritive was cereals, ahead of protein foods, or vegetables and fruit. Nutritional beliefs were not the same in the Antananarivo and Antsiranana areas, nor between urban and rural areas of Antsiranana. Different socio-economic contexts, food availability and information may explain these differences. This study could guide actors involved in nutrition promotion to adapt to specific areas their nutrition programmes in the fight against malnutrition. PMID:24887056

Ramaroson Rakotosamimanana, Vonimihaingo; Arvisenet, Galle; Valentin, Dominique

2014-10-01

416

Air pollution studies in terms of PM2.5, PM2.5-10, PM10, lead and black carbon in urban areas of Antananarivo - Madagascar  

E-print Network

Atmospheric aerosols or particulate matters are chemically complex and dynamic mixtures of solid and liquid particles. Sources of particulate matters include both natural and anthropogenic processes. The present work consists in determining the concentrations of existing elements in the aerosols collected in Andravoahangy and in Ambodin'Isotry in Antananarivo city (Madagascar). The size distribution of these elements and their main sources are also studied. The Total Reflection X-Ray Fluorescence spectrometer is used for the qualitative and quantitative analyses. The results show that the concentrations of the airborne particulate matters PM2.5-10 are higher than those of PM2.5. The identified elements in the aerosol samples are Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb. The average concentrations of these elements are also higher in the coarse particles than in the fine particles. The calculation of the enrichment factors by Mason's model shows that Cr, Ni, Cu, Zn, Br and Pb are of anthropogenic origins. The...

Rasoazanany, E O; Ravoson, H N; Andriambololona, Raoelina; Randriamanivo, L V; Ramaherison, H; Ahmed, H; Harinoely, M

2012-01-01

417

Emergence of rice yellow mottle virus in eastern Uganda: Recent and singular interplay between strains in East Africa and in Madagascar.  

PubMed

Epidemics of rice yellow mottle virus (RYMV) have developed recently in eastern Uganda, close to Lake Victoria in East Africa. Unexpectedly, all isolates from the affected area belonged to a single strain (named S4ug), a strain that is different from the S4lv strain that has been prevalent in the Lake Victoria basin for the past five decades. Interestingly, the S4ug strain is most closely related at the genomic level (except ORF1) to the strain present in Madagascar (S4mg), 2000km away. The minor parent of the S4mg recombinant strain could not be detected. Molecular clock dating analysis indicated that the singular sequence of events - that associated the emergence of a new strain (S4ug), a modular recombination between closely related strains (S4mg and S4ug) and a long distance transmission (S4mg) - occurred recently, within the past few decades. This finding is at variance with the process of gradual strain dispersal and diversification over two centuries throughout Africa that was previously established. PMID:25245592

Ochola, Dennis; Issaka, Souley; Rakotomalala, Mbolarinosy; Pinel-Galzi, Agns; Ndikumana, Innocent; Hubert, Judith; Hbrard, Eugnie; Sr, Yacouba; Tusiime, Geoffrey; Fargette, Denis

2015-01-01

418

Chemical composition and in vitro biological activities of the essential oil of Vepris macrophylla (BAKER) I.VERD. endemic to Madagascar.  

PubMed

Vepris macrophylla is an evergreen tree occurring in sub-humid forest of Madagascar and traditionally used in the Island to treat several complaints as well as to prepare aromatic teas and alcoholic drinks. In the present work, the essential oil distilled from the leaves was analyzed for the first time by gas chromatography (GC-FID) and gas chromatography/mass spectrometry (GC/MS). The major compounds were citral (56.3%), i.e., mixture of neral (23.1%) and geranial (33.2%), citronellol (14.5%), and myrcene (8.3%). The essential oil exhibited antimicrobial activity against S. aureus, P. aeruginosa, and C. albicans as determined by vapor-diffusion assay, supporting the traditional use of the plant for preparing steam bath for the treatment of infectious diseases. The essential oil was evaluated for cytotoxic activity on human tumor cell lines by MTT (=3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay, showing inhibitory effects comparable to those of cisplatin, notably on MDA-MB 231 (human breast adenocarcinoma) and HCT116 (human colon carcinoma) cell lines. Finally, the essential oil was also subjected to screening for its antioxidant activity and the free radical scavenging capacity. PMID:23495153

Maggi, Filippo; Fortun Randriana, Richard; Rasoanaivo, Philippe; Nicoletti, Marcello; Quassinti, Luana; Bramucci, Massimo; Lupidi, Giulio; Petrelli, Dezemona; Vitali, Luca A; Papa, Fabrizio; Vittori, Sauro

2013-03-01

419

Baobab trees (Adansonia) in Madagascar use stored water to flush new leaves but not to support stomatal opening before the rainy season.  

PubMed

Baobab trees (Adansonia, Bombacaceae) are widely thought to store water in their stems for use when water availability is low. We tested this hypothesis by assessing the role of stored water during the dry season in three baobab species in Madagascar. In the dry season, leaves are present only during and after leaf flush. We quantified the relative contributions of stem and soil water during this period through measures of stem water content, sap flow and stomatal conductance. Rates of sap flow at the base of the trunk were near zero, indicating that leaf flushing was almost entirely dependent on stem water. Stem water content declined by up to 12% during this period, yet stomatal conductance and branch sap flow rates remained very low. Stem water reserves were used to support new leaf growth and cuticular transpiration, but not to support stomatal opening before the rainy season. Stomatal opening coincided with the onset of sap flow at the base of the trunk and occurred only after significant rainfall. PMID:16411957

Chapotin, Saharah Moon; Razanameharizaka, Juvet H; Holbrook, N Michele

2006-01-01

420

Cation distribution in a Fe-bearing K-feldspar from Itrongay,Madagascar. A combined neutron- and X-ray single crystal diffractionstudy  

SciTech Connect

We determined the cation distribution and ordering of Si, Al and Fe on the tetrahedral sites of a monoclinic low-sanidine from Itrongay, Madagascar, by combined neutron- and X-ray single-crystal diffraction. The cation distribution was determined by means of a simultaneous refinement using neutron- and X-ray data, as well as by combining scattering densities obtained from separate refinements with chemical data from a microprobe experiment. The two methods give the same results and show that Fe is fully ordered on T1, whereas Al shows a high degree of disorder. Based on this and previously published temperature-dependent X-ray data, we conclude that it is preferential ordering of Fe on T1 even at high temperature, rather than a high diffusion kinetics of Fe, which causes this asymmetry in ordering behavior between Al and Fe. The preferential ordering of Fe3+ relative to Al3+ in T1 is consistent with its 25 percent larger ionic radius.

Ackermann, Sonia; Kunz, Martin; Armbruster, Thomas; Schefer,Jurg; Hanni, Henry

2005-05-02

421

Geochemistry of phlogopite, diopside, calcite, anhydrite and apatite pegmatites and syenites of southern Madagascar: evidence for crustal silicocarbonatitic (CSC) melt formation in a Panafrican collisional tectonic setting  

NASA Astrophysics Data System (ADS)

The phlogopite, diopside, calcite, anhydrite and apatite pegmatites of Ampandrandava and Beraketa are examples for the many other pegmatites of similar silicocarbonatitic composition found in the Bekily and Betroka-Beraketa Precambrian belts of southern Madagascar. The two studied pegmatites and associated syenites crystallised from immiscible silicocarbonatitic and peralkaline syenitic melts in a time span between 515 and 504 Ma in the final extensional phase of the Panafrican continental collision and connected metamorphic/metasomatic event. Model T Nd ages suggest that the melts were produced by partial melting of 3.5 Ga partially evaporitic continental crust. The studied pegmatites and genetically associated syenitic rocks are very rare examples for crustal silicocarbonatitic melts generated in a Panafrican collisional setting. The overwhelming majority of carbonatites and associated peralkaline rocks are mantle derived, much poorer in phosphate and sulfate and found in a cratonic environment. In light of the present results, genetic models for other sulfate- and phosphate-rich magmatic rocks (e.g., phlogopite-apatite-calcite mineralisations in the Grenville-Hasting formation in Canada and in the Sludyanka group in Eastern Siberia) should be reevaluated.

Morteani, G.; Kostitsyn, Y. A.; Gilg, H. A.; Preinfalk, C.; Razakamanana, T.

2013-04-01

422

A new microhylid frog, genus Rhombophryne, from northeastern Madagascar, and a re-description of R. serratopalpebrosa using micro-computed tomography.  

PubMed

The rainforests of the Marojejy massif in northern Madagascar are a well-known hotspot of amphibian species diversity and endemism. In the present paper, we re-describe Rhombophryne serratopalpebrosa (Guib 1975), a cophyline microhylid frog from high altitude on this massif, based on a re-examination of its holotype, and describe Rhombophryne vaventy sp. nov. using characters of external morphology and osteology, illustrated by pdf-embedded comparative 3D models of their skeletons. Rhombophryne serratopalpebrosa differs from R. vaventy sp. nov. by smaller size (28 mm snout-vent length vs. 52.9 mm), skin texture (granular vs. rough and tubercular skin respectively), supratympanic fold shape (strong, long and straight reaching the eye vs. curved and not extending anteriorly beyond the tympanum), relative tympanum diameter (78% vs. 41% of eye diameter), shape of the postchoanal prevomerine palate, shape of the footplate of the columella, length of prepollex, and by other subtle osteological features. Morphological comparisons suggest that a specimen from Ambolokopatrika assigned to R. serratopalpebrosa in previous genetic studies might belong to yet another undescribed species, closely related to R. vaventy sp. nov., whereas DNA sequences of the topotypic R. serratopalpebrosa remain unknown. We therefore emphasise the need for collecting additional material from high altitudes of the Marojejy massif to understand the systematics, as well as the natural history, of this poorly known species. For the new species described herein, we propose a Red List threat status of Vulnerable, in line with other Marojejy endemics from a similar altitude. PMID:25283290

Scherz, Mark D; Ruthensteiner, Bernhard; Vences, Miguel; Glaw, Frank

2014-01-01

423

Living within fallen palm leaves: the discovery of an unknown Blommersia (Mantellidae: Anura) reveals a new reproductive strategy in the amphibians of Madagascar  

NASA Astrophysics Data System (ADS)

We describe a new mantelline frog of the genus Blommersia found in rainforest in North East Madagascar, from the protected areas of Ambatovaky, Betampona, Masoala, and Zahamena. Blommersia angolafa n.sp. is a small frog, with a body size of 17-21 mm, expanded finger and toe tips, and colouration ranging from yellow to dark brown, with pale-bluish spots on the flanks and light tips of fingers and toes. A peculiar aspect characterising this new species is its novel life history and reproductive mode. Both sexes live and breed in a phytotelmic habitat of water accumulated within fallen prophylls and fallen leaf sheaths of at least three species of Dypsis palms. Within these phytotelmata, egg laying and complete larval development occur. Thus, B. angolafa n.sp. represents a new evolutionary lineage of Malagasy frogs in which phytotelmy is known. Up to now, reproduction in phytotelmata in Malagasy frogs has been reported for many cophyline microhylids, most species of Guibemantis, Mantella laevigata, and possibly in a still-undescribed species belonging to the genus Spinomantis. We consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding strategy. The new species, being specialised to a habitat represented by a few selected Dypsis species, potentially suffers the selective exploitation of these palms.

Andreone, Franco; Rosa, Gonalo M.; Nol, Jean; Crottini, Angelica; Vences, Miguel; Raxworthy, Christopher J.

2010-06-01

424

Integrative revision of the giant pill-millipede genus Sphaeromimus from Madagascar, with the description of seven new species (Diplopoda, Sphaerotheriida, Arthrosphaeridae).  

PubMed

The Malagasy giant pill-millipede genus Sphaeromimus de Saussure & Zehntner, 1902 is revised. Seven new species, S. titanus sp. n., S. vatovavy sp. n., S. lavasoa sp. n., S. andohahela sp. n., S. ivohibe sp. n., S. saintelucei sp. n., and S. andrahomana sp. n. were discovered, in one case with the help of sequence data, in the rainforests of southeastern Madagascar. The species are described using light- and scanning electron microscopy. A key to all 10 species of the genus is presented. All but one (S. andohahela) of the newly discovered species are microendemics each occurring in isolated forest fragments. The mitochondrial COI barcoding gene was amplified and sequenced for 18 Sphaeromimus specimens, and a dataset containing COI sequences of 28 specimens representing all Sphaeromimus species (except S. vatovavy) was analyzed. All species are genetically monophyletic. Interspecific uncorrected genetic distances were moderate (4-10%) to high (18-25%), whereas intraspecific variation is low (0-3.5%). Sequence data allowed the correct identification of three colour morphs of S. musicus, as well as the identity of a cave specimen, which although aberrant in its morphology and colouration, was genetically identical to the holotype of S. andrahoma. PMID:25009417

Wesener, Thomas; Le, Daniel Minh-Tu; Loria, Stephanie F

2014-01-01

425

Fifty years of changes in reef flat habitats of the Grand Rcif of Toliara (SW Madagascar) and the impact of gleaning  

NASA Astrophysics Data System (ADS)

The Grand Rcif of Toliara (GRT) in Madagascar is a large (33 km2) barrier reef system of the SW Indian Ocean that had been well investigated in the 1960s and early 1970s. A massive degradation of the reef has been reported since at least the early 1980s, just a few years after research activities ceased in the area. Examination of historical aerial photographs and modern high-resolution remote sensing images confirms a continuous loss of coral habitat on GRT outer reef flats between 1962 and 2011, with an average loss of 65 % and a range of 37-79 % loss during this 50-year period. The usual suspects of coral community declines (cyclones, bleaching and sedimentation) may have contributed to the demise of the GRT. However, an independent study (Salimo 1997) suggests that the chronic pressure of fisherman gleaning on reef flats with destructive tools is the main driver of the observed changes. Salimo's reported level of frequentation (6.8 fishermen per day and per km-2) and rates of destruction per fisherman (7.7 m2 of coral habitat h-1) yield a cumulated overall loss in agreement with the image-based rates of habitat loss. The GRT is unlikely to recover because this chronic stress is unlikely to decrease in the near future. Indeed, the GRT daily provides subsistence fishery resources for local Vezo people and to agriculturalist or pastoralist ethnic groups who have turned to exploiting coastal resources due to increasing aridity and dwindling agricultural and livestock production.

Andrfout, S.; Guillaume, M. M. M.; Delval, A.; Rasoamanendrika, F. M. A.; Blanchot, J.; Bruggemann, J. H.

2013-09-01

426

The Complete Plastid Genome Sequence of Madagascar Periwinkle Catharanthus roseus (L.) G. Don: Plastid Genome Evolution, Molecular Marker Identification, and Phylogenetic Implications in Asterids  

PubMed Central

The Madagascar periwinkle (Catharanthusroseus in the family Apocynaceae) is an important medicinal plant and is the source of several widely marketed chemotherapeutic drugs. It is also commonly grown for its ornamental values and, due to ease of infection and distinctiveness of symptoms, is often used as the host for studies on phytoplasmas, an important group of uncultivated plant pathogens. To gain insights into the characteristics of apocynaceous plastid genomes (plastomes), we used a reference-assisted approach to assemble the complete plastome of C. roseus, which could be applied to other C. roseus-related studies. The C. roseus plastome is the second completely sequenced plastome in the asterid order Gentianales. We performed comparative analyses with two other representative sequences in the same order, including the complete plastome of Coffeaarabica (from the basal Gentianales family Rubiaceae) and the nearly complete plastome of Asclepiassyriaca (Apocynaceae). The results demonstrated considerable variations in gene content and plastome organization within Apocynaceae, including the presence/absence of three essential genes (i.e., accD, clpP, and ycf1) and large size changes in non-coding regions (e.g., rps2-rpoC2 and IRb-ndhF). To find plastome markers of potential utility for Catharanthus breeding and phylogenetic analyses, we identified 41 C. roseus-specific simple sequence repeats. Furthermore, five intergenic regions with high divergence between C. roseus and three other euasterids I taxa were identified as candidate markers. To resolve the euasterids I interordinal relationships, 82 plastome genes were used for phylogenetic inference. With the addition of representatives from Apocynaceae and sampling of most other asterid orders, a sister relationship between Gentianales and Solanales is supported. PMID:23825699

Ku, Chuan; Chung, Wan-Chia; Chen, Ling-Ling; Kuo, Chih-Horng

2013-01-01

427

Spatial distribution and population composition of the brown mouse lemur (Microcebus rufus) in Ranomafana National Park, Madagascar, and its implications for social organization.  

PubMed

Through a 16-mo mark-recapture trap study, I examined aspects of spatial distribution and population composition in the brown mouse lemur, Microcebus rufus, a 42 g nocturnal strepsirhine. The study took place in the rainforest of Ranomafana National Park in southeastern Madagascar. Sherman live traps were set monthly for a variable number of nights in a quasi-grid 50 m apart. Captured individuals were marked for future identification and released at site of capture. More males than females were captured overall (102 versus 72) and at 83% of trap sites. Trap sex ratio fluctuated significantly over the course of the study. It was particularly male-biased between June and August (3.9:1), when more previously uncaptured males than females (14 versus 6) entered the trap population. Some of these males remained in the trap population. Although the average number of individuals captured was not significantly different between the first four and last four months of the study, the composition of the population changed. The female population, however, changed less: 28.9% of all females captured in the first four months of the study were recaptured in the last four months, compared to 9.7% of males. It is suggested that the pattern of appearance of new individuals and disappearance of others, both predominantly male, may indicate migratory activity. Furthermore, an average of eight individuals were captured at each trap site (approximately 70% of traps captured more than five), suggesting a high degree of spatial overlap. The average number of male and female individuals captured in each trap (5.5 males versus 2.5 females), the average number of trap sites at which males and females were captured (3.6 versus 2.4), and the average number of captures for males and females (9.8 versus 5.7) all differed significantly between the sexes. PMID:10811440

Atsalis, S

2000-05-01

428

Ecological Effects of the Invasive Giant Madagascar Day Gecko on Endemic Mauritian Geckos: Applications of Binomial-Mixture and Species Distribution Models  

PubMed Central

The invasion of the giant Madagascar day gecko Phelsuma grandis has increased the threats to the four endemic Mauritian day geckos (Phelsuma spp.) that have survived on mainland Mauritius. We had two main aims: (i) to predict the spatial distribution and overlap of P. grandis and the endemic geckos at a landscape level; and (ii) to investigate the effects of P. grandis on the abundance and risks of extinction of the endemic geckos at a local scale. An ensemble forecasting approach was used to predict the spatial distribution and overlap of P. grandis and the endemic geckos. We used hierarchical binomial mixture models and repeated visual estimate surveys to calculate the abundance of the endemic geckos in sites with and without P. grandis. The predicted range of each species varied from 85 km2 to 376 km2. Sixty percent of the predicted range of P. grandis overlapped with the combined predicted ranges of the four endemic geckos; 15% of the combined predicted ranges of the four endemic geckos overlapped with P. grandis. Levin's niche breadth varied from 0.140 to 0.652 between P. grandis and the four endemic geckos. The abundance of endemic geckos was 89% lower in sites with P. grandis compared to sites without P. grandis, and the endemic geckos had been extirpated at four of ten sites we surveyed with P. grandis. Species Distribution Modelling, together with the breadth metrics, predicted that P. grandis can partly share the equivalent niche with endemic species and survive in a range of environmental conditions. We provide strong evidence that smaller endemic geckos are unlikely to survive in sympatry with P. grandis. This is a cause of concern in both Mauritius and other countries with endemic species of Phelsuma. PMID:24785293

Buckland, Steeves; Cole, Nik C.; Aguirre-Gutirrez, Jess; Gallagher, Laura E.; Henshaw, Sion M.; Besnard, Aurlien; Tucker, Rachel M.; Bachraz, Vishnu; Ruhomaun, Kevin; Harris, Stephen

2014-01-01

429

Multiple colonizations from Madagascar and converged acquisition of dioecy in the Mascarene Dombeyoideae (Malvaceae) as inferred from chloroplast and nuclear DNA sequence analyses  

PubMed Central

Background and Aims In the Mascarenes, a young oceanic archipelago composed of three main islands, the Dombeyoideae (Malvaceae) have diversified extensively with a high endemism rate. With the exception of the genus Trochetia, Mascarene Dombeyoideae are described as dioecious whereas Malagasy and African species are considered to be monocline, species with individuals bearing hermaphrodite/perfect flowers. In this study, the phylogenetic relationships were reconstructed to clarify the taxonomy, understand the phylogeographic pattern of relationships and infer the evolution of the breeding systems for the Mascarenes Dombeyoideae. Methods Parsimony and Bayesian analysis of four DNA markers (ITS, rpl16 intron and two intergenic spacers trnQ-rsp16 and psbM-trnD) was used. The molecular matrix comprised 2985 characters and 48 taxa. The Bayesian phylogeny was used to infer phylogeographical hypotheses and the evolution of breeding systems. Key Results Parsimony and Bayesian trees produced similar results. The Dombeyoideae from the Mascarenes are polyphyletic and distributed among four clades. Species of Dombeya, Trochetia and Ruizia are nested in the same clade, which implies the paraphyly of Dombeya. Additionally, it is shown that each of the four clades has an independent Malagasy origin. Two adaptive radiation events have occurred within two endemic lineages of the Mascarenes. The polyphyly of the Mascarene Dombeyoideae suggests at least three independent acquisitions of dioecy. Conclusions This molecular phylogeny highlights the taxonomic issues within the Dombeyoideae. Indeed, the limits and distinctions of the genera Dombeya, Trochetia and Ruizia should be reconsidered. The close phylogeographic relationships between the flora of the Mascarenes and Madagascar are confirmed. Despite their independent origins and a distinct evolutionary history, each endemic clade has developed a different breeding systems (dioecy) compared with the Malagasy Dombeyoideae. Sex separation appears as an evolutionary convergence and may be the consequence of selective pressures particular to insular environments. PMID:20562131

Le Pchon, Timothe; Dubuisson, Jean-Yves; Haevermans, Thomas; Cruaud, Corinne; Couloux, Arnaud; Gigord, Luc D. B.

2010-01-01

430

Sources of tooth wear variation early in life among known-aged wild ring-tailed lemurs (Lemur catta) at the Bez Mahafaly Special Reserve, Madagascar.  

PubMed

Ring-tailed lemurs (Lemur catta) at the Bez Mahafaly Special Reserve (BMSR), Madagascar display a high frequency of individuals with notable and sometimes extreme tooth wear. Adult lemurs display a range of tooth wear even among individuals of the same age, but we do not know at what age this variation first appears. This study's goal was to determine whether wear variation occurs in younger wild lemurs. Based on the decade-long study of ring-tailed lemur feeding and dental ecology at BMSR, we hypothesized that younger, natal lemurs (under 5 years of age), would display variation in their degree of tooth wear that would correspond to microhabitat differences, given differences in food availability in different troops' home ranges. We also hypothesized that wear would differ between sexes at this young age, given differences in feeding between males and females in this population. Hypotheses were tested using dental topographic analyses using dental impressions collected from known-aged lemurs across 10 years at BMSR. Results illustrate significant differences in wear-related tooth topography (i.e., relief and slope, presented here as "occlusal lift") for microhabitat, sex and troop affiliation among lemurs under 5 years of age in this population. Although, all lemurs in this population consume mechanically challenging tamarind fruit, those in more disturbed habitats eat additional introduced foods, some of which are also mechanically challenging. Thus, dietary variation is the likely cause of variation in tooth wear. The wear variation we show at a young age suggests caution when assigning age based on tooth wear in living and fossil primates. These wear-related tooth shape changes early in life, which reflects sex, habitat variation and levels of anthropogenic disturbance, may potentially impact reproductive fitness later in life. PMID:24953664

Cuozzo, Frank P; Head, Brian R; Sauther, Michelle L; Ungar, Peter S; O'Mara, M Teague

2014-11-01

431

Mode of formation of hibonite (CaAl12O19) within the U-Th skarns from the granulites of S-E Madagascar  

NASA Astrophysics Data System (ADS)

In Madagascar, hibonite occurs as a rather frequent mineral within thorianite-bearing skarns which are widespread in the Pan African granulitic formations constituting the S-E part of the Island (Tranomaro area). In these skarns, leucocratic segregations made up of CO3-scapolite to meionite (Anequivalent=89 95% which implies T?850 C), spinel and corundum were formed at stage 1 of metasomatism in a titanite-bearing matrix consisting of scapolite (Aneq=77 88) and aluminous diopside. During stage 2 of metasomatism, scapolite from the lenses were altered to anorthite+calcite while the less calcic scapolite remained stable which indicates T?800 C. Hibonite crystallized at the expense of corundum and spinel. Expressed as mol% of the CaAl12O19/Ca(Al10TiR2+)O19/REE(Al11R2+)O19 [+Th (Al10R2+ 2)O19] end-members ( R 2+=Mg, Fe2+, Zn2+; Al=Al, Fe3+; Ti=Ti, Si), its composition varies from 26/72/2 to 50/23/27. The ideal activity of the CaAl12O19 component is about 0.25. Fluid inclusions in corundum, hibonite and anorthite are composed of nearly pure CO2. In corundum, the isochores for primary inclusions are in agreement with the P-T estimates for regional metamorphism and stage 1 metasomatism ( T?850 C, P?5 kbar). Inclusions with the highest density in hibonite and anorthite constrain P to about 3 3.5 kbar for T=800 C. Thermodynamic calculations indicate that, in addition to a low activity of CaAl12O19, stability of hibonite in equilibrium with anorthite and calcite implies an extremely low activity of silica (below the zircon-baddeleyite buffer). By contrast the activity of CO2 may be high, in agreement with the observed fluid compositions. These results are corroborated by a short comparison with the other granulite occurrences of hibonite in Tanzania and South India.

Rakotondrazafy, Michel A. F.; Moine, B.; Cuney, M.

1996-03-01

432

More than just talk: the framing of transactional sex and its implications for vulnerability to HIV in Lesotho, Madagascar and South Africa  

PubMed Central

Background 'Transactional sex' was regarded by the mid-1990s as an important determinant of HIV transmission, particularly in sub-Saharan Africa. Little attention has been paid to what the terms used to denote transactional sex suggest about how it is understood. This study provides a nuanced set of descriptions of the meaning of transactional sex in three settings. Furthermore, we discuss how discourses around transactional sex suggest linkages to processes of globalization and hold implications for vulnerability to HIV. Methods The analysis in this article is based on three case studies conducted as part of a multi-country research project that investigated linkages between economic globalization and HIV. In this analysis, we contextualize and contrast the 'talk' about transactional sex through the following research methods in three study sites: descriptions revealed through semi-structured interviews with garment workers in Lesotho; focus groups with young women and men in Antananarivo, Madagascar; and focus groups and in-depth interviews with young women and men in Mbekweni, South Africa. Results Participants' talk about transactional sex reveals two themes: (1) 'The politics of differentiation' reflects how participants used language to demarcate identities, and distance themselves from contextually-based marginalized identities; and (2) 'Gender, agency and power' describes how participants frame gendered-power within the context of transactional sex practices, and reflects on the limitations to women's power as sexual agents in these exchanges. Talk about transactional sex in our study settings supports the assertion that emerging transactional sexual practices are linked with processes of globalization tied to consumerism. Conclusions By focusing on 'talk' about transactional sex, we locate definitions of transactional sex, and how terms used to describe transactional sex are morally framed for people within their local context. We take advantage of an opportunity to comparatively explore such talk across three different study sites, and contribute to a better understanding of both emerging sexual practices and their implications for HIV vulnerability. Our work underlines that transactional sex needs to be reflected as it is perceived: something very different from, but of at least equal concern to, formal sex work in the efforts to curb HIV transmission. PMID:21961516

2011-01-01

433