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Integrated dataset of anatomical, morphological, and architectural traits for plant species in Madagascar



In this work, we present a dataset, which provides information on the structural diversity of some endemic tropical species in Madagascar. The data were from CIRAD xylotheque (since 1937), and were also collected during various fieldworks (since 1964). The field notes and photographs were provided by French botanists; particularly by Francis Hallé. The dataset covers 250 plant species with anatomical, morphological, and architectural traits indexed from digitized wood slides and fieldwork documents. The digitized wood slides were constituted by the transverse, tangential, and radial sections with three optical magnifications. The main specific anatomical traits can be found within the digitized area. Information on morphological and architectural traits were indexed from digitized field drawings including notes and photographs. The data are hosted in the website ArchiWood (
Data Article
Integrated dataset of anatomical, morphological,
and architectural traits for plant species
in Madagascar
Amira Azizan
, Emma Guillon
, Yves Caraglio
Patrick Langbour
, Sébastien Paradis
, Pierre Bonnet
Yannick Brohard
, Christine Heinz
, Nabila Boutahar
Loïc Brancheriau
University of Montpellier, Dept. of Biodiversity, Ecology and Evolution, Montpellier, France
CIRAD, UR BioWooEB, 34398, Montpellier, France
CIRAD, UMR AMAP, 34398, Montpellier, France
article info
Article history:
Received 7 July 2017
Accepted 5 September 2017
Available online 12 September 2017
Morpho-architectural traits
Plant architecture
Wood anatomy
In this work, we present a dataset, which provides information on
the structural diversity of some endemic tropical species in
Madagascar. The data were from CIRAD xylotheque (since 1937),
and were also collected during various eldworks (since 1964).
The eld notes and photographs were provided by French bota-
nists; particularly by Francis Hallé. The dataset covers 250 plant
species with anatomical, morphological, and architectural traits
indexed from digitized wood slides and eldwork documents. The
digitized wood slides were constituted by the transverse, tangen-
tial, and radial sections with three optical magnications. The main
specic anatomical traits can be found within the digitized area.
Information on morphological and architectural traits were
indexed from digitized eld drawings including notes and photo-
graphs. The data are hosted in the website ArchiWood (http://
&2017 The Authors. Published by Elsevier Inc. This is an open
access article under the CC BY license
Contents lists available at ScienceDirect
journal homepage:
Data in Brief
2352-3409/&2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license
Corresponding author.
E-mail address: (L. Brancheriau).
Data in Brief 15 (2017) 9296
Specications Table
Subject area Botany
More specic
subject area
Anatomy, morphology and architecture of plant species
Type of data Tables of anatomical traits and morpho-architectural traits
Images of microscope slides for wood anatomy
Field drawings with notes
How data was
Field observations
Data format Tables in MSExcel format *.xlsx
Images of microscope slides in 24-bit RGB TIFF (1600×1200 pixels)
Digitized eld drawings and notes in 24-bit RGB JPG (300 dpi)
Scanned photographs of 24×36 mm format in 24-bit RGB JPG (600 dpi)
Data source
Data accessibility Data package title: ArchiWood dataset
Resource link:
Identier: doi:10.18167/archiwood/1
Usage rights: Creative Commons Attribution NonCommercial ShareAlike
4.0 International (CC BY-SA-NC 4.0)
Value of the data
The dataset consolidates anatomical, morphological, and architectural traits of plant species from
different sources (xylotheque, eld notes, and photographs).
The described traits of tropical plant species can be useful to understand the biogeographical
variation within species and genera in plant anatomy regarding the ontogeny and structure of
sampled plants.
To understand the diversity of wood characteristics and technological behaviors that directly
governed the choice of tropical timber use.
To understand the relationship between tropical wood structure and certain physical, mechanical,
chemical, and biological properties of the material.
1. Data
Madagascar is an important insular hotspot for biodiversity conservation [11]. More than 80% of
the currently known ora species are endemic to the island [4]. Endemic tropical species in Mada-
gascar are well known for its important value in ecology and economy but are predicted to face mass
extinction in the near future because of global warming and deforestation [2,3]. Identication of
Malagasy vascular plant species was documented and can be accessed via the website Tropicos
(Madagascar catalogue,
The architectural analysis on tropical species as described by [1,7,8] emphasize on the dynamics of
growth and structure of a plant species in the competitive nature of the forest, thereby conforming to
its architectural model. Recent studies of plant architecture may not only provide complimentary
information for species-level identication purposes, but also for understanding plant structure
A. Azizan et al. / Data in Brief 15 (2017) 9296 93
evolution within a clade [10] and their ecological strategies [5,6]. Together with stem anatomy, archi-
tectural variations involving the branching process, rhythmicity, and orientation can be comparatively
analyzed to study the evolution of growth in both temporal and spatial contexts [9].Thisapproachcan
also provide guidelines for tree selection and management in agroforestry practices [12].
The dataset gathers anatomical, morphological, and architectural traits of endemic plant species.
The aims is to promote and to make more accessible for scientic and public use a specic part of the
CIRAD wood collection and unpublished morpho-architectural data from Madagascar. More than
1000 microscopic anatomical wood slides, exclusively available in this open access dataset, were
sampled since the early 20th century and compiled with more than 500 digitized eld notes such as
botanical illustrations and photographs. Because diagrammatic representations of morpho-archi-
tectural traits are essential to assess plant structure and growth, digitized illustrations provided here
may serve as a reference for future architectural analysis and application. Metadata from approxi-
mately 250 indexed plant species also provide new insights to species identication and scientic
research, such as in functional ecology or systematics as well as for forest conservation management.
2. Experimental design, materials and methods
2.1. Microscopic structure of wood
For each species, three microscope slides were prepared consisting of transverse, tangential, and
radial sections (Fig. 1). The slides were then digitized using a camera Olympus DP71 mounted onto a
microscope Olympus BX60. Each slide was digitized with three optical magnications: ×40, ×10 0,
and×200. The images (1600×1200 pixels) were then processed by Archimed Microvision® software
and stored in 24-bit RGB TIFF. Within each image, the main specic anatomical traits can be found,
and these traits were indexed following the List of Microscopic Features for Hardwood Identication
from the IAWA (
2.2. Morphology and architecture of plant structure
Information on morphological and architectural traits were indexed from illustrations of digitized
eld notes (300 dpi 24-bit RGB JPEG) (Fig. 2) and scanned photographs of 24×36 mm format (600 dpi,
24-bit RGB JPEG) from various researches in Madagascar, for extended visual information. The traits
were indexed following the modalities as reviewed in [1,7,8]. Both anatomical and morphological
traits may not apply to all of the species available in the dataset.
2.3. Temporal coverage
Concerning the wood collection, the anatomical slides were sampled since 1937. The eld notes
were reported since 1964 for the photographs, and since 1970 for the illustrations. Each document
Fig. 1. Digitized wood slides highlighting anatomical traits. From left to right: transverse (×40), tangential (×100) and radial
(×200) sections of Givotia madagascariensis Baill.
A. Azizan et al. / Data in Brief 15 (2017) 929694
was digitized and indexed between June 2015 and the end of 2016. This information were never
2.4. Taxonomic coverage
The dataset gathered information on 102 families and 244 genera of angiosperm species (with the
addition of a bryophyte). For these species, the updated taxonomic names were provided and
retrieved from The Plant List ( Some traits were specied at the family
or genus level.
This work was supported by the French Digital Scientic Library (BSN5, 2014, ArchiWood project).
The authors would like to thank Laurence Dedieu (Cirad, Dist) for her valuable comments that
helped us to improve this article.
Transparency document. Supplementary material
Transparency data associated with this article can be found in the online version at http://dx.doi.
Fig. 2. Fieldwork illustrations of morpho-architectural traits. Diagrammatic representation of Givotia madagascariensis Baill for
whole plant (left) and branching system (right).
A. Azizan et al. / Data in Brief 15 (2017) 9296 95
[1] D. Barthelemy, Y. Caraglio, Plant architecture: a dynamic, multilevel and comprehensive approach to plant form, structure
and ontogeny, Ann. Bot. 99 (3) (2007) 375407.
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[5] C. Castellanos, D. Kolterman, M. Vester HF, Architectural analysis of Buxus vahlii Baill. (Buxaceae) in two different envir-
onments in Puerto Rico, Adansonia 33 (1) (2011) 7180.
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explain population cover, Oikos 124 (6) (2014) 707716.
[7] F. Hallé, R.A. Oldeman, Essai sur larchitecture et dynamique de la croissance des arbres tropicaux, Masson et cie., Paris
(1970) 178.
[8] F. Hallé, R.A. Oldeman, P. Tomlinson, Tropical Trees and Forests, Springer-Verlag, Berlin (1978) 444.
[9] S. Isnard, J. Prosperi, S. Wanke, S. Wagner, M. Samain, S. Trueba, L. Frenzke, C. Neinhuis, N. Rowe, Growth form evolution in
Piperales and its relevance for understanding angiosperm diversication: an integrative approach combining plant
architecture, anatomy, and biomechanics, Int. J. Plant Sci. 173 (6) (2012) 610639.
[10] D. Johnson, Phylogenetic signicance of spiral and distichous architecture in the Annonaceae, Syst. Bot. 28 (3) (2003)
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Nature 403 (2000) 853858.
[12] K. Tondjo, L. Brancheriau, S. Sabatier, A.D. Kokutse, A. Akossou, K. Kokou, T. Fourcaud, Is the variability of key wood
properties linked with the variability of key architectural traits? Case of planted Teak in Togo regarding thinning and
provenance, Ann. For. Sci. 72 (6) (2014) 717729.
A. Azizan et al. / Data in Brief 15 (2017) 929696
... These afore mentioned examples demonstrate that morphological characters could infer a direct correlation with genotypic variations which could be useful to breeders attempting interspecific crosses (Azizan et al., 2017;Meyer & Meola, 1978;Small, 2013). ...
The objective of our research was to contrast the resonance techniques on tubers with the more commonly used morphological analyses. With the aims of establishing a classification among ecotypes and food fingerprint of mashua tuber, a multivariable data analysis like principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA), were performed with morphological and metabolomic profiling data. Accordingly, the morphological traits showed a clear separation among most of the studied ecotypes. For a 1H NMR metabolic profiling, at least 35 compounds were identified in tubers. The relative concentration of these compounds was used to perform a PCA and OPLS-DA analysis. A clear separation, according to PC1 = 31.7%, was between TTE_01 & TTE_02 and the ecotypes TTE_06 and TTE_05 with significantly higher concentrations of disaccharides such as maltose and sucrose. Amino acids such as proline and alanine were found and organic acid including succinic, fumaric, formic and acetic acid. In contrast, TTE_05 and TTE_06 ecotypes contained higher concentrations of monosaccharides such as fructose, glucose. Metabolic profile demonstrated to be a more reliable technique than morphological analysis for classification of ecotypes.
... Plants have evolved several adaptations to survival in different environments by regulating their development and growth (Mizutani and Kanaoka, 2017). Comparative studies of plant anatomy, morphology and physiology provide knowledge on structures unique to a taxonomic group (Rebeiz and Tsiantis, 2017), and supply additional data sets for understanding plant structure and behaviour as well as their survival strategies (Azizan et al., 2017). J. curcas is an oilseed crop which is considered as a promising source of renewable feedstock for biodiesel production and known to be well adapted to arid environments (Heller, 1996;Islam et al., 2011;Jongschaap et al., 2007). ...
The life cycle of a seed plant involves subsequent stages of development including germination and seedling establishment. Morphological structures have a fundamental role in these phases, since they are strongly related to physiological adaptations to survival in a range of environments. The present study describes an important morphophysiological and anatomical pattern in embryos of Jatropha genus, involving adaptations for germination and seedling growth. Seed embryos of Jatropha curcas, J. gossypiifolia, J. podagrica and J. multifida were examined using different physiological and microscopic assays. Jatropha species present a multimeristematic embryo composed of one main apical primary meristem plus four radial primary meristems. Seed germination is completed by simultaneous protrusion of five functional roots and seedlings are able to survive even with only one of them. The hypocotyl-radicle transition zone exhibiting different stomata sizes, ontogenic phases and short lifespan limited to the germination. Stomata fractures at mid-region due to the fact that guard cells were not lengthen as neighboring epidermal cells, forming a large cavity in the epidermal tissue during seedling growth. The results showed an unusual and complex root structure for the Jatropha genus. The presence of stomata operating strictly during seed germination could be associated to intense energetic metabolism demanded for the simultaneous growth of the five roots originated from the multimeristematic radicle. This study provides important insights into the understanding of seed germination of Jatropha species in response to stress environmental conditions.
Full-text available
Some species of Annonaceae have been reported to have a spiral arrangement of branches on their orthotropic axes while other species have a distichous arrangement of branches, but the systematic distribution of this morphological difference in the family has not been studied. Growth architecture was surveyed for 48 genera and 100 species of Annonaceae using original observations of living plants and reports from the literature. The spiral branching pattern was found in all species of 27 genera examined, while distichous branching architecture characterized the other 21 genera. Architecture pattern is correlated with a difference in the orientation of the apical meristem of the primary shoot: in plants with spiral architecture the apex is erect; in plants with distichous architecture the apex is horizontal or drooping. The architecture data show remarkable congruence with recent infra-familial phylogenies constructed on the basis of rbcL and trnL-trnF sequence data, supporting several rearrangements of genera in the classification of this family, and may be more widely useful in the systematics of Annonaceae.
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Plant architecture is related to the performance of long-lived plants; its role in promoting species coexistence and in successional patterns is now widely recognized. However, because plant architecture involves branching processes, it is highly variable at the intra-specific level. In this paper, we address two questions: What is the best way to describe plant architecture to obtain meaningful information for explaining population cover: at the whole-plant level, or at the level of its unitary constituent parts? Further, are there architectural designs related to populations’ success? We evaluated the relative impact of ontogeny and whole-plant traits on the cover achieved by the populations of five shrub species developing on 25 abandoned farmlands in southwestern Québec (Canada). We compared four ways of analyzing plant architecture: 1-2) using morphological traits described at the scale of a module (an elementary architectural unit made up of all the different types of shoots), with or without taking into account the ontogeny of the whole organism, 3) using the rate of changes during ontogeny as traits, and 4) using whole-plant traits describing branching processes at a scale larger than modules. We then used variation partitioning to discriminate the actual effects of these traits on percent cover of the species from hidden effects due to plant ontogenesis and population spatial structure. Our results suggest that the predominant variables that effectively describe population cover vary from one species to another. At the same time, whole-plant architectural traits and the rate of change of morphological traits during ontogeny both have an important effect on population cover. These findings suggest that acknowledging the developmental pattern of woody species can clarify the impact of intra-specific trait variation on population cover.
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A striking feature of early angiosperm lineages is the variety of life forms and growth forms, which ranges from herbs, aquatic herbs, climbers, and epiphytes to woody shrubs and trees. This morphological and anatomical diversity is arguably one of the factors explaining how angiosperms dominate many ecosystems worldwide. However, just how such a wide spectrum of growth forms has evolved in angiosperms remains unclear. In this review, we investigate patterns of growth form diversification in Piperales, an early-diverging lineage (with stem age estimated at 201–128 Myr ago) and the most morphologically diverse clade among magnoliids. We outline patterns of growth form diversity and architecture as well as the biomechanical significance of developmental characters, such the organization, loss, and gain of woodiness. Asaroideae and Saururaceae are terrestrial as well as semiaquatic to aquatic herbaceous perennials bearing rhizomes. The Aristolochioideae and Piperaceae show higher levels of growth form diversity and biomechanical organization, with complex patterns of increasing or decreasing woodiness and architectural organization. The climbing habit has probably evolved independently in the Aristolochiaceae and Piperaceae, while mechanically unstable shrubs and, less frequently, treelets have evolved several times within these two most species-rich clades. A key developmental character underlying diversity in most Piperales—with the exception of the herbaceous Saruma (Asaroideae)—is the conserved development of the wood cylinder, in which fusiform initials are limited to fascicular cambial initials. The resulting large fraction of raylike tissue in the stem—a highly characteristic feature of woody species in the Piperales—potentially introduced mechanical constraints on the diversification of self-supporting architectures. This was possibly circumvented by the architectural development of repeated, large-diameter meristems in some shrublike habits via sympodial growth. Patterns of growth form evolution within Piperales potentially mirror some of the overall trends observed among early-diverging angiosperms as a whole as well as angiosperms in general. These include profound changes in life form and growth form linked to large-scale transitions in woodiness, diversity of mechanical organization, and shifts in architectural development.
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Background and aims - The Catalogue of the Vascular Plants of Madagascar project aims to evaluate and enumerate the native and naturalized vascular plant flora of Madagascar. In light of the past two decades of intensive collecting and taxonomic work, all relevant published literature and available specimens are being reassessed in order to evaluate the taxonomic status and distribution of the native and naturalized taxa of vascular plants. Here we provide current figures for the total numbers of vascular plants and levels of endemism at the order, family, genus and species levels, comparing them to previous historical counts and analyzing the distribution of the non-endemic element of the flora.Key Results - At the time of writing (April 2010), more than a century after Baron first counted 4,100 species of vascular plants in Madagascar, the Madagascar Catalogue database had registered a total of 14,883 accepted names at all taxonomic levels (64 orders, 243 families, 1,730 genera, 11,220 species and 1,626 infraspecific taxa). Of the 11,220 species of vascular plants in Madagascar, 10,650 (95%) are angiosperms, of which 331 are naturalized introduced species. The remaining accepted indigenous angiosperm species total 10,319, of which 8,621 (84%) are endemic to Madagascar (82% endemism for all indigenous vascular plants). Among the 1,698 non-endemic species of indigenous angiosperms, a total of 1,372 (81%) also occur in Africa, of these 654 (39%) are present only in Africa and Madagascar.
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Analyse de l'architecture de Buxus vahlii Baill. (Buxaceae) dans deux environnements différents à Porto Rico. L'analyse de l'architecture de Buxus vahlii Baill. (Buxaceae) à l'ouest de Porto Rico est présentée. Deux populations qui différent dans leurs caractéristiques environnementales ont été étudiées: le premier environnement est la forêt côtière dans la commune de Rincón, le deuxième est une forêt de montagne sur des sols calcaires dans la commune d'Isabela. Buxus vahlii croît selon le modèle de Champagnat. Quatre stades de développement des arbres ont été identifiés: germination, arbre juvénile, arbre mature et arbre sénescent. Le tronc et les branches de l'arbre sont de type sympodial, par la superposition d'axes orthotropiques mixtes. Deux formes de cimes différentes ont été observées pour B. vahlii à Porto Rico: dans la forêt de Rincón, B. vahlii pousse selon un modèle laminaire, tandis que dans la forêt d'Isabela, il peut croître selon un modèle en forme de cône ou de coupe.
Key messageA retrospective architectural analysis performed on planted teaks in Togo showed that the variation of wood radial properties were linked with tree ontogeny, and that these relationships depended on thinning practices and provenance.ContextVariability in growth, flowering and forking in individual trees according to origin and/or thinning practices may affect wood structure and consequently impact wood physical properties. We tested this hypothesis in teak.AimsWe sought evidence of: (1) origin effects (Togolese versus Tanzanian teak) on growth, flowering, cambial growth and wood properties; (2) thinning effects on these variables and (3) relationships between tree ontogeny and radial variations of wood properties.MethodsA retrospective architectural analysis was used to draw stem growth and near infrared spectroscopy to assess radial variations of wood properties.ResultsFlowering reflects tree vigour and began at an earlier age in Togolese than in Tanzanian provenances. No differences were detected in regards to growth ring surface area, basic density and modulus of elasticity. Both systematic and selective thinnings improved growth without impacting the two latter properties. Stabilization of the growth ring area observed at 4 years old was associated with a decline in stem annual extension with a 1-year time lag.Conclusions Architectural analyses showed that radial growth was linked with tree ontogeny. This method can be extended to subsequent developmental stages, i.e. to older trees with economic interest, and used to determine architectural traits that are useful in tree selection.
AimDespite considerable attention to climate change, no global assessment of the consequences of sea level rise is available for insular ecosystems. Yet, over 180,000 islands world-wide contain 20% of the world's biodiversity. We investigated the consequences of sea level rise for the 10 insular biodiversity hotspots world-wide and their endemic species. This assessment is crucial to identify areas with the highest risk of inundation and the number of endemic species at risk of potential extinction. LocationTen insular biodiversity hotspots including the Caribbean islands, the Japanese islands, the Philippines, the East Melanesian islands, Polynesia-Micronesia, Sundaland, Wallacea, New Caledonia, New Zealand and Madagascar and the Indian Ocean islands (i.e. 4447 islands). Methods We investigated four scenarios of projected sea level rise (1, 2, 3 and 6m) on these islands. For each scenario, we assessed the number of islands that would be entirely and partially submerged by overlying precise digital elevation model and island data. We estimated the number of endemic species for each taxon (i.e. plants, birds, reptiles, mammals, amphibians and fishes) potentially affected by insular habitat submersion using the endemic-area relationship. ResultsBetween 6 and 19% of the 4447 islands would be entirely submerged under considered scenarios (1-6m of sea level rise). Three hotspots displayed the most significant loss of insular habitat: the Caribbean islands, the Philippines and Sundaland, representing a potential threat for 300 endemic species. Main conclusionsWith the current estimates of global sea level rise of at least 1m by 2100, large parts of ecosystems of low-lying islands are at high risk of becoming submerged, leading to significant habitat loss world-wide. Therefore, the threat posed by sea level rise requires specific policies that prioritize insular biota on islands at risk as a result of near future sea level rise.
Nearly half the world's vascular plant species and one-third of terrestrial vertebrates are endemic to 25 “hotspots” of biodiversity, each of which has at least 1500 endemic plant species. None of these hotspots have more than one-third of their pristine habitat remaining. Historically, they covered 12% of the land's surface, but today their intact habitat covers only 1.4% of the land. As a result of this habitat loss, we expect many of the hotspot endemics to have either become extinct or—because much of the habitat loss is recent—to be threatened with extinction. We used World Conservation Union [ IUCN ] Red Lists to test this expectation. Overall, between one-half and two-thirds of all threatened plants and 57% of all threatened terrestrial vertebrates are hotspot endemics. For birds and mammals, in general, predictions of extinction in the hotspots based on habitat loss match numbers of species independently judged extinct or threatened. In two classes of hotspots the match is not as close. On oceanic islands, habitat loss underestimates extinction because introduced species have driven extinctions beyond those caused by habitat loss on these islands. In large hotspots, conversely, habitat loss overestimates extinction, suggesting scale dependence (this effect is also apparent for plants). For reptiles, amphibians, and plants, many fewer hotspot endemics are considered threatened or extinct than we would expect based on habitat loss. This mismatch is small in temperate hotspots, however, suggesting that many threatened endemic species in the poorly known tropical hotspots have yet to be included on the IUCN Red Lists. We then asked in which hotspots the consequences of further habitat loss (either absolute or given current rates of deforestation) would be most serious. Our results suggest that the Eastern Arc and Coastal Forests of Tanzania-Kenya, Philippines, and Polynesia-Micronesia can least afford to lose more habitat and that, if current deforestation rates continue, the Caribbean, Tropical Andes, Philippines, Mesoamerica, Sundaland, Indo-Burma, Madagascar, and Chocó–Darién–Western Ecuador will lose the most species in the near future. Without urgent conservation intervention, we face mass extinctions in the hotspots. Resumen: Casi la mitad del total de plantas vasculares del mundo y un tercio de los vertebrados terrestres son endémicos en 25 “áreas críticas” para la biodiversidad, cada una de las cuales tiene por lo menos 1500 especies de plantas endémicas. En ninguno de estos sitios permanece más de un tercio de su hábitat prístino. Históricamente, cubrían 12% de la superficie terrestre, pero en la actualidad su hábitat intacto cubre solo 1.4% del terreno. Como resultado de esta pérdida de hábitat esperamos que muchas de las especies endémicas a estos sitios estén extintas o – porque la pérdida de hábitat es reciente – se encuentren amenazadas de extinción. Utilizamos Listas Rojas de UICN para comprobar esta predicción. En general, entre la mitad y dos tercios de las plantas amenazadas y el 57% de los vertebrados terrestres amenazados son endémicos de áreas críticas para la biodiversidad. Para aves y mamíferos en general, las predicciones de extinción en las áreas críticas para la biodiversidad, basadas en la pérdida de hábitat, coinciden con el número de especies consideradas extintas o amenazadas independientemente. En dos clases de áreas críticas para la biodiversidad la coincidencia no es muy grande. En islas oceánicas, la pérdida de hábitat subestima la extinción porque las especies introducidas han causado más extinciones que las producidas por la reducción del hábitat. Por lo contrario, la pérdida de hábitat sobrestima la extinción en áreas críticas para la biodiversidad extensas, lo que sugiere una dependencia de escala (este efecto también es aparente para plantas). Para reptiles, anfibios y plantas mucho menos especies endémicas son consideradas amenazadas o extintas por pérdida de hábitat. Sin embargo, esta discordancia es pequeña en áreas críticas para la biodiversidad en zonas templadas templadas, lo que sugiere que muchas especies endémicas amenazadas en las poco conocidas áreas críticas para la biodiversidad en zonas tropicales aun están por incluirse en las Listas Rojas. Posteriormente nos preguntamos en que áreas críticas para la biodiversidad serían más serias las consecuencias de una mayor pérdida de hábitat (absoluta o con las tasas actuales de deforestación). Nuestros resultados sugieren que el Arco Oriental y los Bosques Costeros de Tanzania/Kenia, Filipinas, Polinesia/Micronesia no pueden soportar mayores pérdidas y que, si continúan las tasas de deforestación actuales, el Caribe, Andes Tropicales, Filipinas, Mesoamérica, Sundaland, Indo-Burma, Madagascar y Chocó/Darién/Ecuador Occidental perderán más especies en el futuro. Sin acciones urgentes de conservación, habrá extinciones masivas en las áreas críticas para la biodiversidad.
Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify 'biodiversity hotspots' where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a 'silver bullet' strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the world's species at risk.