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1.
Mol Phylogenet Evol ; 130: 81-91, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30321698

RESUMO

North Africa is a climatically and topographically complex region with unique biotic assemblages resulting from the combination of multiple biogeographic realms. Here, we assess the role of climate in promoting intra-specific diversification in a Palearctic relict, the North African fire salamander, Salamandra algira, using a combination of phylogenetic and population genetic analyses, paleoclimatic modelling and niche overlap tests. We used mitochondrial DNA (Cyt-b), 9838 ddRADseq loci, and 14 microsatellite loci to characterize patterns of genetic diversity and population structure. Phylogenetic analyses recover two major clades, each including several lineages with mito-nuclear discordances suggesting introgressive patterns between lineages in the Middle Atlas, associated with a melting pot of genetic diversity. Paleoclimatic modelling identified putative climatic refugia, largely matching areas of high genetic diversity, and supports the role of aridity in promoting allopatric diversification associated with ecological niche conservatism. Overall, our results highlight the role of climatic microrefugia as drivers of populations' persistence and diversification in the face of climatic oscillations in North Africa, and stress the importance of accounting for different genomic regions when reconstructing biogeographic processes from molecular markers.


Assuntos
Filogenia , Salamandra/classificação , África do Norte , Animais , DNA Mitocondrial/genética , Ecossistema , Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Modelos Biológicos , Filogeografia , Salamandra/genética
2.
Naturwissenschaften ; 100(9): 877-89, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23942550

RESUMO

The identification of species-rich areas and their prognosticated turnover under climate change are crucial for the conservation of endemic taxa. This study aims to identify areas of reptile endemicity richness in a global biodiversity hot spot (Morocco) under current and future climatic conditions and to investigate the role of protected areas in biodiversity conservation under climate change. Species distribution models (SDM) were performed over the distribution of 21 endemic reptiles, combined to estimate current species richness at 1 × 1 km resolution and projected to years 2050 and 2080 according to distinct story lines and ensemble global circulation models, assuming unlimited and null dispersion ability. Generalized additive models were performed between species richness and geographic characteristics of 43 protected areas. SDM found precipitation as the most important factor related to current species distributions. Important reductions in future suitable areas were predicted for 50 % of species, and four species were identified as highly vulnerable to extinction. Drastic reductions in species-rich areas were predicted for the future, with considerable variability between years and dispersal scenarios. High turnover rates of species composition were predicted for eastern Morocco, whereas low values were forecasted for the Northern Atlantic coast and mountains. Species richness for current and future conditions was significantly related to the altitude and latitude of protected areas. Protected areas located in mountains and/or in the Northern Atlantic coast were identified as refugia, where population monitoring and conservation management is needed.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Répteis/fisiologia , Animais , Modelos Teóricos , Marrocos
3.
Sci Total Environ ; 732: 139205, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32438172

RESUMO

Fire is one of the main disturbances to terrestrial environments, transforming habitat structure and affecting community composition. Coupled with fire, forest type and vegetation structure modulate the taxonomic response to fire by ectotherm organisms such as reptiles. The response of each reptile species to fire is based on their functional attributes, which make some species resilient to fire and others vulnerable to that disturbance and only adapted to long-unburnt landscapes. We studied the functional response of a reptile community at 13 burnt sites within the African rim of the Western Mediterranean, and in two contrasting forest types, i.e. native cork oak forests (five sites) and pine plantations (eight sites). We compiled seven functional traits for the reptile species in the study areas, and quantified reptile functional diversity at each sampled plot. Variation in this index was examined from burnt to nearby unburnt plots, both in cork oak and pine forests, with generalized linear mixed models. Redundancy analysis was used to identify which functional traits were associated with particular plot types. We found 2149 individual reptiles from 15 species. The functional response of reptiles to fire was forest-type dependent: functional richness did not change with fire in cork oak forest plots, but increased with fire in the pine plantation ones. High reptile functional richness in cork oak plots was due to high species richness in this forest type. The functional-redundancy analysis showed that cork oak forest hosts a reptile community functionally composed of small Mediterranean ground- and rock-dwelling lizards. In pine plantation plots, however, saxicolous geckos and phytophagous tortoises indicate the availability of other microhabitat and food resources to be exploited by reptile species with different functional traits.


Assuntos
Lagartos , Tartarugas , Animais , Biodiversidade , Florestas , Pinus , Quercus
4.
PLoS One ; 14(8): e0220969, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31419242

RESUMO

Fire is a key ecological process in several biomes worldwide. Over recent decades, human activities (e.g. rural abandonment, monoculture plantations) and global warming are magnifying the risk of fire, with changes in fire intensity and frequency. Here, we offer the first study that examines the impact of fire on the spur-thighed tortoise Testudo graeca living in a native cork oak forest and pine plantation in north-western Africa. A total of 44 transects (22 burnt and 22 unburnt) were sampled at 8 sites affected by fires of natural cork oak forest and pine plantation with 8 surveys per site in 2015-2017 (264 hours of sampling effort). Tortoise densities were estimated with line-transect distance sampling. The detection probability of tortoises was higher in burnt (0.915) than unburnt (0.474) transects. The density of tortoises was negatively associated with elevation and declined with fire by c. 50% in both forest types. The negative response of T. graeca to fire should be considered in conservation planning of this species in north-western Africa in a future scenario of changes in fire regime.


Assuntos
Conservação dos Recursos Naturais , Monitorização de Parâmetros Ecológicos/tendências , Incêndios , Florestas , Tartarugas , África do Norte , África Ocidental , Animais , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Pinus , Densidade Demográfica , Quercus
5.
Zoology (Jena) ; 110(1): 9-19, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17161594

RESUMO

Eurosiberian vipers have been considered model organisms, and studies on their reproductive ecology have afforded much of the current knowledge concerning viviparity in snakes. However, such studies are biased towards northern species and there is little information on Mediterranean species and/or populations. The reproductive ecology of Vipera latastei in the Iberian Peninsula was studied by analysing a large sample of specimens from collections, to better understand the conservation status of this Mediterranean viper. Males and females matured at small and similar body sizes (240 and 265 mm snout-vent length, respectively) and reproductive cycles in both sexes were seasonal. Spermatogenesis peaked in August, vitellogenesis developed in spring and the timing of the mating period was puzzling, with populations mating in autumn, spring, or in both seasons. The most striking finding was that adult females reproduced triennially on average. Lataste's viper is currently in continuous decline in the IP, and most of its populations are isolated in Mediterranean mountains. We hypothesize that prey scarcity and the brevity of the activity period in mountain habitats diminishes the ability of vipers to recover over the short term the energy expended in reproduction. The species needs 2 years for the acquisition and storage of energy ("capital breeder"), and a third year for the expenditure of this energy (in vitellogenesis and embryogenesis), a year during which females feed consistently ("income breeder"). Thus, this viper combines both strategies to supply the reproductive energy cost. Current decline in population and distribution, together with a poor capacity to renew populations, renders Lataste's viper vulnerable to environmental stochasticity.


Assuntos
Ecossistema , Tamanho da Ninhada de Vivíparos/fisiologia , Maturidade Sexual/fisiologia , Viperidae/fisiologia , Animais , Corpo Adiposo/fisiologia , Comportamento Alimentar , Feminino , Masculino , Estações do Ano
6.
Biol Rev Camb Philos Soc ; 89(1): 215-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23848599

RESUMO

Deserts and arid regions are generally perceived as bare and rather homogeneous areas of low diversity. The Sahara is the largest warm desert in the world and together with the arid Sahel displays high topographical and climatic heterogeneity, and has experienced recent and strong climatic oscillations that have greatly shifted biodiversity distribution and community composition. The large size, remoteness and long-term political instability of the Sahara-Sahel, have limited knowledge on its biodiversity. However, over the last decade, there have been an increasing number of published scientific studies based on modern geomatic and molecular tools, and broad sampling of taxa of these regions. This review tracks trends in knowledge about biodiversity patterns, processes and threats across the Sahara-Sahel, and anticipates needs for biodiversity research and conservation. Recent studies are changing completely the perception of regional biodiversity patterns. Instead of relatively low species diversity with distribution covering most of the region, studies now suggest a high rate of endemism and larger number of species, with much narrower and fragmented ranges, frequently limited to micro-hotspots of biodiversity. Molecular-based studies are also unravelling cryptic diversity associated with mountains, which together with recent distribution atlases, allows identifying integrative biogeographic patterns in biodiversity distribution. Mapping of multivariate environmental variation (at 1 km × 1 km resolution) of the region illustrates main biogeographical features of the Sahara-Sahel and supports recently hypothesised dispersal corridors and refugia. Micro-scale water-features present mostly in mountains have been associated with local biodiversity hotspots. However, the distribution of available data on vertebrates highlights current knowledge gaps that still apply to a large proportion of the Sahara-Sahel. Current research is providing insights into key evolutionary and ecological processes, including causes and timing of radiation and divergence for multiple taxa, and associating the onset of the Sahara with diversification processes for low-mobility vertebrates. Examples of phylogeographic patterns are showing the importance of allopatric speciation in the Sahara-Sahel, and this review presents a synthetic overview of the most commonly hypothesised diversification mechanisms. Studies are also stressing that biodiversity is threatened by increasing human activities in the region, including overhunting and natural resources prospection, and in the future by predicted global warming. A representation of areas of conflict, landmines, and natural resources extraction illustrates how human activities and regional insecurity are hampering biodiversity research and conservation. Although there are still numerous knowledge gaps for the optimised conservation of biodiversity in the region, a set of research priorities is provided to identify the framework data needed to support regional conservation planning.


Assuntos
Biodiversidade , Evolução Biológica , Conservação dos Recursos Naturais , África do Norte , Animais , Clima Desértico
7.
Integr Zool ; 4(2): 188-195, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21392289

RESUMO

Northwestern Morocco is undergoing a sudden change in the level of infrastructure growth and pressure on the environment from increased tourism. The ongoing changes are raising questions about how the ecosystem will react, and the relevant drivers of these changes. The Oued Laou valley in north-west Morocco hosts high landscape, species and human cultural diversity. The Talassemtane National Park has been established to preserve the environment in this region; however, what information tools are available to children regarding this environment? The ecosystem is illustrated here using three components: herpetofauna (representing ecosystem components), problems related to water quantity and quality (representing interactions within ecosystem components) and Talassemtane National Park (representing a case of ecosystem management). A children's book was written on this topic, and when the book was delivered to pupils, a questionnaire was included, aimed at determining their sources of environmental information. The results identified major changes in the sources of information utilized by children in this part of Morocco, a clear role of schools in explaining ecosystem components, and an increasing role of TV in environmental information supply. The role of the family was found to be less important than TV or school. Another major source of pupils' environmental knowledge is personal observation and hands-on experience, both for rural and urban children. Children are willing to discover and understand complex systems, and researchers should be encouraged to supply children with correct and up-to-date information on environmental systems, focusing at first on the local environment, as a background for sustainable development.


Assuntos
Ecossistema , Meio Ambiente , Disseminação de Informação/métodos , População , Adolescente , Criança , Família , Feminino , Humanos , Masculino , Marrocos , Instituições Acadêmicas , Inquéritos e Questionários , Televisão
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