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Rood E.,Oxford Brookes University | Rood E.,Netherlands Center for Biodiversity Naturalis section | Ganie A.A.,Fauna and Flora International Indonesia Programme | Ganie A.A.,Bandung Institute of Technology | And 2 more authors.
Diversity and Distributions | Year: 2010

Aim Asian elephants, Elephas maximus, are threatened throughout their range by a combination of logging, large scale forest conversion and conflict with humans. We investigate which environmental factors, both biotic and abiotic, constrain the current distribution of elephants. A spatially explicit habitat model is constructed to find core areas for conservation and to assess current threats.Location Ulu Masen Ecosystem in the province of Nanggroe Aceh Darussalam on the island of Sumatra, Indonesia.Methods A stratified survey was conducted at 12 sites (300 transects) to establish the presence of elephants. Presence records formed the basis to model potential habitat use. Ecological niche factor analysis (ENFA) is used to describe their niche and to identify key factors shaping elephant distribution. An initial niche model was constructed to describe elephant niche structure, and a second model focused on identifying core areas only. To assess the threat of habitat encroachment, overlap between the elephants' optimal niche and the occurrence of forest encroachment is computed.Results Elephants were recorded throughout the study area from sea level to 1600 m a.s.l. The results show that the elephant niche and consequently habitat use markedly deviates from the available environment. Elephant presence was positively related to forest cover and vegetation productivity, and elephants were largely confined to valleys. A spatially explicit model showed that elephants mainly utilize forest edges. Forest encroachment occurs throughout the elephants range and was found within 80% of the elephants' ecological niche.Main conclusions In contrast to general opinion, elephant distribution proved to be weakly constrained by altitude, possibly because of movement routes running through mountainous areas. Elephants were often found to occupy habitat patches in and near human-dominated areas. This pattern is believed to reflect the displacement of elephants from their former habitat. © 2010 Blackwell Publishing Ltd.


Ruffinatto F.,University of Turin | Macchioni N.,CNR Tree and Timber Institute | Boetto G.,University of Turin | Baas P.,Netherlands Center for Biodiversity Naturalis Section | Zanuttini R.,University of Turin
IAWA Journal | Year: 2010

Species identification is a crucial step in the study of wooden artefacts, but sampling is frequently impossible. The objective of this study is to evaluate the efficacy of reflected light microscopy, including the use of polarising and narrow-band blue filters, as a non-invasive identification tool. Different surfacing and finishing techniques copying historical manufacturing methods were applied to selected species. The visibility of anatomical features was evaluated on the basis of a four level scale. Two indexes were created: an Identifiable Anatomical Features index (IAF) to evaluate the effect of treatments on the complex of microstructural characters, and a Feature Recognition Index (FRI) to estimate the susceptibility of each anatomical feature towards different treatments. Surfacing affected the visibility of anatomical features to different degrees of severity depending both on the technique used and on the species. The visibility could be partially improved or decreased by the presence of finishes, depending on their transparency. Each anatomical feature showed different susceptibilities towards treatments. Both polarising and narrow-band blue filters considerably increased visibility of several anatomical features. Possibilities to recognise individual character states were encouraging, except when obscured by low transparency finishes. Much diagnostic anatomical information can be obtained by the use of non-invasive, reflected light microscopy, although the step from feature recognition to species identification may still require further analysis.


Lens F.,Netherlands Center for Biodiversity Naturalis section | Eeckhout S.,Institute of Botany and Microbiology | Eeckhout S.,Ghent University | Zwartjes R.,Netherlands Center for Biodiversity Naturalis section | And 4 more authors.
Annals of Botany | Year: 2012

Background and AimsThe family Balsaminaceae is essentially herbaceous, except for some woodier species that can be described as 'woody' herbs or small shrubs. The family is nested within the so-called balsaminoid clade of Ericales, including the exclusively woody families Tetrameristaceae and Marcgraviaceae, which is sister to the remaining families of the predominantly woody order. A molecular phylogeny of Balsaminaceae is compared with wood anatomical observations to find out whether the woodier species are derived from herbaceous taxa (i.e. secondary woodiness), or whether woodiness in the family represents the ancestral state for the order (i.e. primary woodiness). MethodsWood anatomical observations of 68 Impatiens species and Hydrocera triflora, of which 47 are included in a multigene phylogeny, are carried out using light and scanning electron microscopy and compared with the molecular phylogenetic insights. Key ResultsThere is much continuous variation in wood development between the Impatiens species studied, making the distinction between herbaceousness and woodiness difficult. However, the most woody species, unambiguously considered as truly woody shrubs, all display paedomorphic wood features pointing to secondary woodiness. This hypothesis is further supported by the molecular phylogeny, demonstrating that these most woody species are derived from herbaceous (or less woody) species in at least five independent clades. Wood formation in H. triflora is mostly confined to the ribs of the stems and shows paedomorphic wood features as well, suggesting that the common ancestor of Balsaminaceae was probably herbaceous. ConclusionsThe terms 'herbaceousness' and 'woodiness' are notoriously difficult to use in Balsaminaceae. However, anatomical observations and molecular sequence data show that the woodier species are derived from less woody or clearly herbaceous species, demonstrating that secondary woodiness has evolved in parallel. © The Author 2012. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.


Jacquemyn H.,Catholic University of Leuven | Merckx V.,Netherlands Center for Biodiversity Naturalis section | Brys R.,Research Institute for Nature and Forest | Tyteca D.,Catholic University of Louvain | And 4 more authors.
New Phytologist | Year: 2011

The specificity of orchids for their fungi can vary substantially, from highly specialist interactions to more generalist interactions, but little is known about the evolutionary history of the mycorrhizal specificity of orchids. • Here, we used a network analysis approach to investigate orchid mycorrhizal associations in 16 species of the genus Orchis sampled across 11 different regions in Europe. We first examined in detail the structure of the network of associations and then tested for a phylogenetic signal in mycorrhizal specificity and identified the fungi with which the orchids associated. • We found 20 different fungal lineages that associated with species of the genus Orchis, most of them being related to members of the Tulasnellaceae (84.33% of all identified associations) and a smaller proportion being related to members of the Ceratobasidiaceae (9.97%). Species associations formed a nested network that is built on asymmetric links among species. Evolution of mycorrhizal specificity in Orchis closely resembles a Brownian motion process, and the interaction between Orchis and Tulasnellaceae fungi is significantly influenced by the phylogenetic relationships between the Orchis species. • Our results provide evidence of the presence of phylogenetic conservatism in mycorrhizal specificity in orchids and demonstrate that evolutionary processes may be an important factor in generating patterns of mycorrhizal associations. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.


Couvreur T.L.P.,IRD Montpellier | Porter-Morgan H.,New York Botanical Garden | Porter-Morgan H.,City University of New York | Wieringa J.J.,Netherlands Center for Biodiversity Naturalis Section | And 2 more authors.
BMC Evolutionary Biology | Year: 2011

Background: The tropical rain forests (TRF) of Africa are the second largest block of this biome after the Amazon and exhibit high levels of plant endemism and diversity. Two main hypotheses have been advanced to explain speciation processes that have led to this high level of biodiversity: allopatric speciation linked to geographic isolation and ecological speciation linked to ecological gradients. Both these hypotheses rely on ecology: in the former conservation of ecological niches through time is implied, while in the latter adaptation via selection to alternative ecological niches would be a prerequisite. Here, we investigate the role of ecology in explaining present day species diversity in African TRF using a species level phylogeny and ecological niche modeling of two predominantly restricted TRF tree genera, Isolona and Monodora (Annonaceae). Both these genera, with 20 and 14 species, respectively, are widely distributed in African TRFs, with a few species occurring in slightly less humid regions such as in East Africa. Results: A total of 11 sister species pairs were identified most of them occurring in allopatry or with little geographical overlap. Our results provide a mixed answer on the role of ecology in speciation. Although no sister species have identical niches, just under half of the tests suggest that sister species do have more similar niches than expected by chance. PCA analyses also support little ecological differences between sister species. Most speciation events within both genera predate the Pleistocene, occurring during the Late Miocene and Pliocene periods. Conclusions: Ecology is almost always involved in speciation, however, it would seem to have had a little role in species generation within Isolona and Monodora at the scale analyzed here. This is consistent with the geographical speciation model for TRF diversification. These results contrast to other studies for non-TRF plant species where ecological speciation was found to be an important factor of diversification. The Pliocene period appears to be a vital time in the generation of African TRF diversity, whereas Pleistocene climatic fluctuations have had a smaller role on speciation than previously thought. Ecological niche modeling, species level phylogeny, ecological speciation, African tropics, Isolona, Monodora, Annonaceae. © 2011 Couvreur et al; licensee BioMed Central Ltd.


Vonk R.,Netherlands Center for Biodiversity Naturalis section | Hoeksema B.W.,Netherlands Center for Biodiversity Naturalis | Jaume D.,CSIC - Mediterranean Institute for Advanced Studies
ZooKeys | Year: 2011

Psammogammarus wallacei sp. n. is described from the shallow marine interstitial of a sand and coral rubble beach on the Gura Ici islands (North Moluccas; Indonesia). This is the first record of this circumtropical genus from SE Asia, with the geographically closest relative inhabiting the Ryukyu archipelago in Japan. The new species is highly distinctive by the display of sexual dimorphism on pleopod II, with the medial margin of the male proximal article of exopod provided with a comb of short, blunt curved spinules; no other representative of the genus is known to display sexually-dimorphic appendages aside of the gnathopods. The new species is also noteworthy by the outline of the palm margin of male gnathopod II, hardly excavated, and by showing a carpus broader than long. An overview of the genus Psammogammarus with 14 species to date is provided. Copyright Ronald Vonk et al.


Alvarez-Presas M.,University of Barcelona | Mateos E.,University of Barcelona | Vila-Farre M.,University of Barcelona | Sluys R.,University of Amsterdam | And 2 more authors.
Molecular Phylogenetics and Evolution | Year: 2012

The land planarian species Microplana terrestris (Müller, 1774), shows a wide distribution in the north of the Iberian Peninsula, where mature humid forests can be found. Since most terrestrial planarians require the presence and good condition of wet forests to survive, a parallel evolution of the taxon and its habitat might be expected. Performing molecular analyses (mitochondrial cytochrome oxidase I and nuclear ITS-1 genes) we estimated the demography and biogeographic history of the species in that region. Our results show the species to present levels of genetic diversity likely originating before the Pleistocene. However, it presents a genetic structure that presumably resulted from its survival in various refuges during the Pleistocene glacial cycles. The two main genetic groups, present on the Iberian Peninsula, seem to have different origins: the western one being of Iberian origin, while the eastern group may have been the result of a re-colonization from the north. In both cases, their biogeographical history mirrors their habitat range movements, reinforcing the phylogeographical hypothesis put forward for its preferred habitat, i.e. humid forests. © 2012 Elsevier Inc..


Osorio L.,Catholic University of Leuven | Trujillo E.,Catholic University of Leuven | Van Vuure A.W.,Catholic University of Leuven | Lens F.,Netherlands Center for Biodiversity Naturalis section | And 3 more authors.
ECCM 2012 - Composites at Venice, Proceedings of the 15th European Conference on Composite Materials | Year: 2012

Bamboo fibres are an attractive alternative to reinforce polymers in the new era of green composite materials. A new mechanical process has been developed to extract long bamboo fibres from the Colombian species Guadua angustifolia. The mechanical properties of technical fibres have been studied, the tensile strength and Young's Modulus are around 800 MPa and 43 GPa respectively. To fully explore these excellent mechanical properties and to make an adequate use of this new material as reinforcement, it is indispensable to have a complete understanding of fibre behaviour as a function of the microstructure. Observations have provided us with a vast knowledge of the complex microstructure of this fibre from the macro down to the micro scale level, where different features like the distribution of the elementary fibres within the fibre bundle, dimensions and the layering pattern of the elementary fibres and the main microfibril angles could be measured.


PubMed | Netherlands Center for Biodiversity Naturalis section
Type: Journal Article | Journal: Annals of botany | Year: 2012

The family Balsaminaceae is essentially herbaceous, except for some woodier species that can be described as woody herbs or small shrubs. The family is nested within the so-called balsaminoid clade of Ericales, including the exclusively woody families Tetrameristaceae and Marcgraviaceae, which is sister to the remaining families of the predominantly woody order. A molecular phylogeny of Balsaminaceae is compared with wood anatomical observations to find out whether the woodier species are derived from herbaceous taxa (i.e. secondary woodiness), or whether woodiness in the family represents the ancestral state for the order (i.e. primary woodiness).Wood anatomical observations of 68 Impatiens species and Hydrocera triflora, of which 47 are included in a multigene phylogeny, are carried out using light and scanning electron microscopy and compared with the molecular phylogenetic insights.There is much continuous variation in wood development between the Impatiens species studied, making the distinction between herbaceousness and woodiness difficult. However, the most woody species, unambiguously considered as truly woody shrubs, all display paedomorphic wood features pointing to secondary woodiness. This hypothesis is further supported by the molecular phylogeny, demonstrating that these most woody species are derived from herbaceous (or less woody) species in at least five independent clades. Wood formation in H. triflora is mostly confined to the ribs of the stems and shows paedomorphic wood features as well, suggesting that the common ancestor of Balsaminaceae was probably herbaceous.The terms herbaceousness and woodiness are notoriously difficult to use in Balsaminaceae. However, anatomical observations and molecular sequence data show that the woodier species are derived from less woody or clearly herbaceous species, demonstrating that secondary woodiness has evolved in parallel.


Psammogammarus wallaceisp. n. is described from the shallow marine interstitial of a sand and coral rubble beach on the Gura Ici islands (North Moluccas; Indonesia). This is the first record of this circum-tropical genus from SE Asia, with the geographically closest relative inhabiting the Ryukyu archipelago in Japan. The new species is highly distinctive by the display of sexual dimorphism on pleopod II, with the medial margin of the male proximal article of exopod provided with a comb of short, blunt curved spinules; no other representative of the genus is known to display sexually-dimorphic appendages aside of the gnathopods. The new species is also noteworthy by the outline of the palm margin of male gnathopod II, hardly excavated, and by showing a carpus broader than long. An overview of the genus Psammogammarus with 14 species to date is provided.

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