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1.
Sci Rep ; 14(1): 569, 2024 01 04.
Article in English | MEDLINE | ID: mdl-38177203

ABSTRACT

Since Malagasy human culture became established in a multi-layered way by genetic admixture of Austronesian (Indonesia), Bantu (East Africa) and West Asian populations, the Malagasy native livestock should also have originated from these regions. While recent genetic studies revealed that Malagasy native dogs and goats were propagated from Africa, the origin of Malagasy native chickens is still controversial. Here, we conducted a phylogeographic analysis of the native chickens, focusing on the historical relationships among the Indian Ocean rim countries and based on mitochondrial D-loop sequences. Although previous work suggested that the rare Haplogroup D occurs with high frequencies in Island Southeast Asia-Pacific, East Africa and Madagascar, the major mitochondrial lineage in Malagasy populations is actually not Haplogroup D but the Sub-haplogroup C2, which is also observed in East Africa, North Africa, India and West Asia. We demonstrate that the Malagasy native chickens were propagated directly from West Asia (including India and North Africa), and not via East Africa. Furthermore, they display clear genetic differentiation within Madagascar, separated into the Highland and Lowland regions as seen in the human genomic landscape on this island. Our findings provide new insights for better understanding the intercommunion of material/non-material cultures within and around Madagascar.


Subject(s)
Chickens , DNA, Mitochondrial , Animals , Africa , Chickens/genetics , DNA, Mitochondrial/genetics , Genetic Variation , Genetics, Population , Haplotypes/genetics , Madagascar , Mitochondria/genetics , Phylogeny
2.
Nat Commun ; 13(1): 4127, 2022 07 26.
Article in English | MEDLINE | ID: mdl-35882849

ABSTRACT

Resolving ecological-economic trade-offs between biodiversity and yields is a key challenge when addressing the biodiversity crisis in tropical agricultural landscapes. Here, we focused on the relation between seven different taxa (trees, herbaceous plants, birds, amphibians, reptiles, butterflies, and ants) and yields in vanilla agroforests in Madagascar. Agroforests established in forests supported overall 23% fewer species and 47% fewer endemic species than old-growth forests, and 14% fewer endemic species than forest fragments. In contrast, agroforests established on fallows had overall 12% more species and 38% more endemic species than fallows. While yields increased with vanilla vine density and length, non-yield related variables largely determined biodiversity. Nonetheless, trade-offs existed between yields and butterflies as well as  reptiles. Vanilla yields were generally unrelated to richness of trees, herbaceous plants, birds, amphibians, reptiles, and ants, opening up possibilities for conservation outside of protected areas and restoring degraded land to benefit farmers and biodiversity alike.


Subject(s)
Ants , Butterflies , Amphibians , Animals , Biodiversity , Birds , Conservation of Natural Resources , Forests , Plants , Reptiles , Trees
3.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Article in English | MEDLINE | ID: mdl-35165148

ABSTRACT

Sustainable land-system transformations are necessary to avert biodiversity and climate collapse. However, it remains unclear where entry points for transformations exist in complex land systems. Here, we conceptualize land systems along land-use trajectories, which allows us to identify and evaluate leverage points, i.e., entry points on the trajectory where targeted interventions have particular leverage to influence land-use decisions. We apply this framework in the biodiversity hotspot Madagascar. In the northeast, smallholder agriculture results in a land-use trajectory originating in old-growth forests and spanning from forest fragments to shifting hill rice cultivation and vanilla agroforests. Integrating interdisciplinary empirical data on seven taxa, five ecosystem services, and three measures of agricultural productivity, we assess trade-offs and cobenefits of land-use decisions at three leverage points along the trajectory. These trade-offs and cobenefits differ between leverage points: Two leverage points are situated at the conversion of old-growth forests and forest fragments to shifting cultivation and agroforestry, resulting in considerable trade-offs, especially between endemic biodiversity and agricultural productivity. Here, interventions enabling smallholders to conserve forests are necessary. This is urgent since ongoing forest loss threatens to eliminate these leverage points due to path dependency. The third leverage point allows for the restoration of land under shifting cultivation through vanilla agroforests and offers cobenefits between restoration goals and agricultural productivity. The co-occurring leverage points highlight that conservation and restoration are simultaneously necessary to avert collapse of multifunctional mosaic landscapes. Methodologically, the framework highlights the importance of considering path dependency along trajectories to achieve sustainable land-system transformations.


Subject(s)
Agriculture , Biodiversity , Conservation of Natural Resources/methods , Forestry , Models, Biological , Animals , Humans , Madagascar
4.
Ecol Evol ; 11(2): 682-687, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33520157

ABSTRACT

Predation can take unexpected turns. For instance, various invertebrate species-most commonly spiders-may prey on vertebrates. Here, we report one observation of a spider (Sparassidae, Damastes sp.) feeding on an amphibian (Hyperoliidae, Heterixalus andrakata) inside a retreat in northeastern Madagascar. To our knowledge, this is the second report of vertebrate predation by spiders in Madagascar. Three additional observations of retreats built by the same spider species show that the spiders built similar retreats and were hiding at the rear end of the retreat. The retreats were built by weaving two green leaves together which were still attached to the tree. We speculate from the observations, that the retreat serves as a targeted trap that deceives frogs seeking shelter during daytime.

5.
Zootaxa ; 4545(4): 563-577, 2019 Jan 21.
Article in English | MEDLINE | ID: mdl-30790891

ABSTRACT

The Marojejy Massif in northern Madagascar is a constant source of herpetological surprises. Herein we describe a new species of leaf-mimicking leaf-tailed gecko, Uroplatus finaritra sp. nov., based on morphological and molecular phylogenetic evidence. This new species inhabits the rainforests of Marojejy National Park at low elevations and is morphologically similar to Uroplatus phantasticus, but differs by having a larger body size, relatively shorter tail, and dark-red pigmentation of the oral mucosa. Molecular data reveals a distance of 14.0-14.7% in the 16S rRNA gene to U. phantasticus, and haplotype sharing in the c-mos nuclear gene only with species of much shorter tails (i.e., with U. kelirambo and two undescribed candidate species). Similar to other members of the leaf-mimicking Uroplatus species in northern Madagascar, Uroplatus finaritra sp. nov. likely has a small geographic distribution, and is currently known only from the lowland rainforests of Marojejy. We discuss the value of the buccal mucosa colouration and tail dimensions of Uroplatus as taxonomic characters, and the potential drivers of their evolution. In order to reduce the risk of international trade under incorrect species names we suggest that exported CITES species should be obligatorily accompanied by information about their precide geographic origin within Madagascar.


Subject(s)
Lizards , Parks, Recreational , Animals , Madagascar , Phylogeny , RNA, Ribosomal, 16S
6.
Zoolog Sci ; 36(4): 294-298, 2019 Aug.
Article in English | MEDLINE | ID: mdl-34664899

ABSTRACT

In the present study, we estimated the genetic diversity and relationships, as well as the propagation routes, of Madagascan goats using mtDNA control region and SRY gene sequences. The mtDNA sequences of 40 Madagascan goats revealed 10 haplotypes and a quite low nucleotide diversity (0.0014), suggesting a founder and/or bottleneck effect resulting from goat migration to Madagascar island. The analysis of sequences identical to Madagascan haplotypes indicated close genetic relationships between goats from Madagascar and Africa. Sequence analysis of the SRY gene in 40 male Madagascan goats revealed two haplotypes: Y1A (45%) and Y2A (55%). The paternal result indicated genetic influences from Africa, South Asia, and the Near East proximal to Madagascar. The analyses of the mtDNA control region and SRY gene sequences suggested a genetic relationship between Africa and Madagascar. Moreover, SRY sequences indicated influences from South Asia and the Near East. These phylogenetic results provide important genetic information for elucidating the propagation routes of Madagascan goats.

7.
Zootaxa ; 4006(1): 143-60, 2015 Aug 21.
Article in English | MEDLINE | ID: mdl-26623762

ABSTRACT

We describe a new leaf-tailed gecko species of the Uroplatus ebenaui group from the eastern central rainforests of Madagascar, which had previously been considered as a confirmed candidate species. Our description of Uroplatus fiera sp. nov. relies on integrating evidence from molecular and morphological characters and is based on newly collected material from two localities. A phylogenetic analysis based on multiple mitochondrial DNA fragments places the new species as sister to a lineage of uncertain status (Uroplatus ebenaui [Ca8]), and the clade consisting of these two lineages is sister to a further undescribed candidate species (U. ebenaui [Ca1]). This entire clade is sister to U. phantasticus plus another candidate species. The new species differs from these close relatives, and all other congenerics, by strong differences in DNA sequences of mitochondrial genes (>8.5% uncorrected p-distance in 16S rDNA to all nominal species of the genus) and lacks shared alleles with any of the nominal species in the nuclear CMOS gene. From its closest relatives the new species further differs in its much smaller tail size (relative to U. phantasticus), and a narrower tail, fewer supralabials, and more toe lamellae (relative to U. ebenaui [Ca1]). Morphologically the new species is most similar to U. ebenaui but differs in its larger body size and unpigmented oral mucosa. Given its distribution in central eastern Madagascar, with records from near Fierenana and Ambatovy, its range overlaps with that of U. phantasticus. Based on examination of the U. phantasticus holotype, we confirm that this latter has a blackish pigmented oral mucosa as do those specimens typically attributed to this nomen, thereby confirming its distinctness from U. fiera sp. nov., in which the mucosa is unpigmented.


Subject(s)
Lizards/anatomy & histology , Lizards/classification , Animals , DNA, Mitochondrial/genetics , Female , Lizards/genetics , Madagascar , Male , Phylogeny , RNA, Ribosomal, 16S , Rainforest , Species Specificity
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