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6 results on '"MORPHOLOGICAL CLASSIFICATION"'

1. Morphology and features of Cambrian oncoids and responses to palaeogeography of the North China Platform

Author

Tehseen Zafar, Shu Jiang, Enzhao Xiao, and Ming-Xiang Mei

Subjects
010506 paleontology, Outcrop, Terrigenous sediment, Miaolingian series, Geochemistry, Girvanella, Morphological classification, 010502 geochemistry & geophysics, 01 natural sciences, Carbon and oxygen isotopes, Sedimentary depositional environment, chemistry.chemical_compound, North China, Microbial mat, chemistry, lcsh:Paleontology, Facies, Carbonate, lcsh:QE701-760, Geology, 0105 earth and related environmental sciences, Oncolite
Abstract

The Cambrian strata in the North China Platform are fully exposed. A wide variety of carbonate oncoids with different shapes occur in the Xuzhuang and Zhangxia formations (Miaolingian Series) from six Cambrian sections in the study area. A comprehensive study involving outcrop description, microscopic observation, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and carbon and oxygen isotope analysis is conducted to determine the facies, morphology, internal structure, and geochemical properties of the oncoids. The oncoids are divided into six types based on their morphology and internal structure. Microscopic and ultrastructural observations reveal typical microbial fossils (Girvanella) and microbially-related sediments (framboidal pyrite), indicating the biogenicity of the oncoids. Additionally, the XRD and carbon and oxygen isotope analysis results suggest that the formational environments of these oncoids are different due to terrestrial influences. Statistical data on the oncoids from the six sections show that there are obvious differences in the types of oncoids and the proportions of different varieties in each section. The spatial differences in the oncoid morphologies are associated with different palaeogeographic settings. The rough oncoid growth patterns developed in nearshore environments were influenced by terrigenous debris and steep terrain, whereas the delicate oncoid growth patterns developed in offshore environments were less affected by terrestrial factors and were featured by more stable depositional processes related to microbial mats.

Published
2020

2. Concept Lattice-Based Classification in NLP

Author

László Kovács

Subjects
Artificial neural network, business.industry, Computer science, lcsh:A, Construct (python library), morphological classification, Object (computer science), Base (topology), Part of speech, Machine learning, computer.software_genre, 01 natural sciences, 010305 fluids & plasmas, Set (abstract data type), formal concept analysis, machine learning, 0103 physical sciences, Formal concept analysis, Artificial intelligence, natural language processing, lcsh:General Works, 010306 general physics, business, computer, Natural language
Abstract

Classification in discrete object space is a widely used machine learning technique. In this case, we can construct a rule set using attribute level implication rules. In this paper, we apply the technique of formal concept analysis to generate the rule base of the classification. This approach is suitable for cases where the number of possible attribute subsets is limited. For testing of this approach, we investigated the problem of the part of speech prediction in natural language texts. The proposed model provides a better accuracy and execution cost than the baseline back-propagation neural network method.

Published
2020

3. A high-throughput stereo-imaging system for quantifying rape leaf traits during the seedling stage

Author

Di Wu, Guoxing Chen, Meng Liu, Lejun Yu, Wanneng Yang, Xiong Xiong, Qian Liu, Ni Jiang, Kede Liu, and Lizhong Xiong

Subjects
0106 biological sciences, 0301 basic medicine, Canopy, Biomass (ecology), biology, Research, Morphological classification, Plant Science, biology.organism_classification, Individual leaf traits, 01 natural sciences, Cross-validation, Random forest, Correlation, 03 medical and health sciences, 030104 developmental biology, Stereo imaging, Agronomy, Stereo-imaging system, Seedling, Genetics, Canopy three-dimensional structure, Stage (hydrology), 010606 plant biology & botany, Biotechnology
Abstract

Background The fitness of the rape leaf is closely related to its biomass and photosynthesis. The study of leaf traits is significant for improving rape leaf production and optimizing crop management. Canopy structure and individual leaf traits are the major indicators of quality during the rape seedling stage. Differences in canopy structure reflect the influence of environmental factors such as water, sunlight and nutrient supply. The traits of individual rape leaves traits indicate the growth period of the rape as well as its canopy shape. Results We established a high-throughput stereo-imaging system for the reconstruction of the three-dimensional canopy structure of rape seedlings from which leaf area and plant height can be extracted. To evaluate the measurement accuracy of leaf area and plant height, 66 rape seedlings were randomly selected for automatic and destructive measurements. Compared with the manual measurements, the mean absolute percentage error of automatic leaf area and plant height measurements was 3.68 and 6.18%, respectively, and the squares of the correlation coefficients (R2) were 0.984 and 0.845, respectively. Compared with the two-dimensional projective imaging method, the leaf area extracted using stereo-imaging was more accurate. In addition, a semi-automatic image analysis pipeline was developed to extract 19 individual leaf shape traits, including 11 scale-invariant traits, 3 inner cavity related traits, and 5 margin-related traits, from the images acquired by the stereo-imaging system. We used these quantified traits to classify rapes according to three different leaf shapes: mosaic-leaf, semi-mosaic-leaf, and round-leaf. Based on testing of 801 seedling rape samples, we found that the leave-one-out cross validation classification accuracy was 94.4, 95.6, and 94.8% for stepwise discriminant analysis, the support vector machine method and the random forest method, respectively. Conclusions In this study, a nondestructive and high-throughput stereo-imaging system was developed to quantify canopy three-dimensional structure and individual leaf shape traits with improved accuracy, with implications for rape phenotyping, functional genomics, and breeding. Electronic supplementary material The online version of this article (doi:10.1186/s13007-017-0157-7) contains supplementary material, which is available to authorized users.

Published
2016

4. The zCOSMOS survey

Author

Zucca E., Bardelli S., Bolzonella M., Zamorani G., Ilbert O., Pozzetti L., Mignoli M., Kova, #269, Lilly S., Tresse L., Tasca L., Cassata P., Halliday C., Vergani D., Caputi K., Carollo C. M., Contini T., Kneib J. P., Le Fèvre O., Mainieri V., Renzini A., Scodeggio M., Bongiorno A., Coppa G., de La Torre S., de Ravel L., Franzetti P., Garilli B., Iovino A., Kampczyk P., Knobel C., Lamareille F., Le Borgne J. F., Le Brun V., Maier C., Pellò R., Peng Y., Perez Montero E., Ricciardelli E., Silverman J. D., Tanaka M., Abbas U., Bottini D., Cappi A., Guzzo L., Koekemoer A. M., Leauthaud A., Maccagni D., Marinoni C., McCracken H. J., Meme, P., Meneux B., Oesch P., Porciani C., Scaramella R., Arnouts S., Aussel H., Capak P., Kartaltepe J., Salvato M., Sanders D., Scoville N., Taniguchi Y., Thompson D., CUCCIATI, OLGA, CIMATTI, ANDREA, MORESCO, MICHELE ENNIO MARIA, INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astronomico di Bologna (OABO), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), AUTRES, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), University of Chicago, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), INAF- Milano, Dipartimento di Fisica, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB)-Università degli Studi di Milano = University of Milan (UNIMI), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Tokai University, Istituto di Astrofisica Spaziale e Fisica cosmica - Bologna (IASF-Bo), Space Telescope Science Institute (STSci), Centre de Physique Théorique - UMR 6207 (CPT), Université de la Méditerranée - Aix-Marseille 2-Université de Provence - Aix-Marseille 1-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Materials & Process technology, Boeing Company [Chicago], California Institute of Technology (CALTECH), Sea Mammal Research Unit, St Andrews, Astronomy, Zucca E., Bardelli S., Bolzonella M., Zamorani G., Ilbert O., Pozzetti L., Mignoli M., Kova&#269, K., Lilly S., Tresse L., Tasca L., Cassata P., Halliday C., Vergani D., Caputi K., Carollo C. M., Contini T., Kneib J.-P., Le Fèvre O., Mainieri V., Renzini A., Scodeggio M., Bongiorno A., Coppa G., Cucciati O., de La Torre S., de Ravel L., Franzetti P., Garilli B., Iovino A., Kampczyk P., Knobel C., Lamareille F., Le Borgne J.-F., Le Brun V., Maier C., Pellò R., Peng Y., Perez-Montero E., Ricciardelli E., Silverman J. D., Tanaka M., Abbas U., Bottini D., Cappi A., Cimatti A., Guzzo L., Koekemoer A. M., Leauthaud A., Maccagni D., Marinoni C., McCracken H. J., Meme, P., Meneux B., Moresco M., Oesch P., Porciani C., Scaramella R., Arnouts S., Aussel H., Capak P., Kartaltepe J., Salvato M., Sanders D., Scoville N., Taniguchi Y., Thompson D., Università di Bologna, Dipartimento di Astronomia, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Università degli Studi di Milano-Bicocca [Milano] (UNIMIB)-Università degli Studi di Milano [Milano] (UNIMI), Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Université de Provence - Aix-Marseille 1-Université de la Méditerranée - Aix-Marseille 2, and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
Normalization (statistics), Cosmology and Nongalactic Astrophysics (astro-ph.CO), High density, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, 01 natural sciences, Luminosity, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], MORPHOLOGICAL CLASSIFICATION, 1ST EPOCH DATA, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Density field, FIELD, 10. No inequality, 010303 astronomy & astrophysics, PHOTOMETRIC REDSHIFTS, Astrophysics::Galaxy Astrophysics, galaxies: statistics, Luminosity function (astronomy), Physics, REDSHIFT SURVEY, LEGACY SURVEY, 010308 nuclear & particles physics, Galaxies: evolution, Galaxies: luminosity function, mass function, Galaxies: statistics, Astronomy and Astrophysics, Space and Planetary Science, VLT DEEP SURVEY, B band, Galaxy, galaxies: luminosity function, mass function, COLOR-DENSITY RELATION, galaxies: luminosity function, mass function, DIGITAL SKY SURVEY, galaxies: evolution, Cosmic time, SURVEY COSMOS, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

(Abridged) We studied the evolution in the B band luminosity function to z~1 in the zCOSMOS 10k sample, for which both accurate galaxy classifications and a detailed description of the local density field are available. The global LF exhibits a brightening of ~0.7 mag in M* from z~0.2 to z~0.9. At low z, late types dominate at faint magnitudes, while the bright end is populated mainly by early types. At higher z, late-type galaxies evolve significantly and, at z~1, the contribution from the various types to the bright end of the LF is comparable. The evolution for early types is in both luminosity and normalization. A similar behaviour is exhibited by late types, but with an opposite trend for the normalization. Studying the role of the environment, we find that the global LF of galaxies in overdense regions has always a brighter M* and a flatter slope. In low density environments, the main contribution to the LF is from blue galaxies, while for high density environments there is an important contribution from red galaxies to the bright end. The differences between the global LF in the two environments are not due to only a difference in the relative numbers of red and blue galaxies, but also to their relative luminosity distributions: the value of M* for both types in underdense regions is always fainter than in overdense environments. The "specular" evolution of late- and early-type galaxies is consistent with a scenario where a part of blue galaxies is transformed in red galaxies with increasing cosmic time, without significant changes in the fraction of intermediate-type galaxies. The bulk of this tranformation in overdense regions probably happened before z~1, while it is still ongoing at lower z in underdense environments., Comment: 18 pages, 10 figures, A&A in press

Published
2009

5. The bimodality of the 10k zCOSMOS-bright galaxies up to z ~ 1: a new statistical and portable classification based on the optical galaxy properties

Author

Coppa G., Mignoli M., Zamorani G., Bardelli S., Lilly S. J., Bolzonella M., Scodeggio M., Vergani D., Nair P., Pozzetti L., Zucca E., Carollo C. M., Contini T., Le Fèvre O., Renzini A., Mainieri V., Bongiorno A., Caputi K. I., de la Torre S., de Ravel L., Franzetti P., Garilli B., Memeo P., Iovino A., Kampczyk P., Kneib J. P., Knobel C., Koekemoer A. M., Kova, #269, Lamareille F., Le Borgne J. F., Le Brun V., Maier C., Pellò R., Peng Y., Perez Montero E., Ricciardelli E., Scarlata C., Silverman J. D., Tanaka M., Tasca L., Tresse L., Abbas U., Bottini D., Capak P., Cappi A., Cassata P., Fumana M., Guzzo L., Leauthaud A., Maccagni D., Marinoni C., Meneux B., Oesch P., Porciani C., Scaramella R., Scoville N., CIMATTI, ANDREA, CUCCIATI, OLGA, Coppa G., Mignoli M., Zamorani G., Bardelli S., Lilly S. J., Bolzonella M., Scodeggio M., Vergani D., Nair P., Pozzetti L., Cimatti A., Zucca E., Carollo C. M., Contini T., Le Fèvre O., Renzini A., Mainieri V., Bongiorno A., Caputi K. I., Cucciati O., de la Torre S., de Ravel L., Franzetti P., Garilli B., Memeo P., Iovino A., Kampczyk P., Kneib J.-P., Knobel C., Koekemoer A. M., Kova&#269, K., Lamareille F., Le Borgne J.-F., Le Brun V., Maier C., Pellò R., Peng Y., Perez-Montero E., Ricciardelli E., Scarlata C., Silverman J. D., Tanaka M., Tasca L., Tresse L., Abbas U., Bottini D., Capak P., Cappi A., Cassata P., Fumana M., Guzzo L., Leauthaud A., Maccagni D., Marinoni C., Meneux B., Oesch P., Porciani C., Scaramella R., Scoville N., Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astronomico di Bologna (OABO), University of Chicago, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), European Southern Observatory (ESO), College of Computing (GATECH), Georgia Institute of Technology [Atlanta], AUTRES, Dipartimento di Fisica, Università degli Studi di Milano-Bicocca [Milano] (UNIMIB)-Università degli Studi di Milano [Milano] (UNIMI), Ecole Polytechnique Fédérale de Lausanne (EPFL), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Département Informatique pour les Systèmes Coopératifs Ouverts et Décentralisés (ISCOD-ENSMSE), École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut Henri Fayol, Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Hunan Normal University, Spitzer Science Center, California Institute of Technology (CALTECH), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique - UMR 6207 (CPT), Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Université de Provence - Aix-Marseille 1-Université de la Méditerranée - Aix-Marseille 2, Astronomy, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB)-Università degli Studi di Milano = University of Milan (UNIMI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Hunan Normal University (HNU), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), and Université de la Méditerranée - Aix-Marseille 2-Université de Provence - Aix-Marseille 1-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, STAR-FORMATION, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], MORPHOLOGICAL CLASSIFICATION, 0103 physical sciences, Range (statistics), PHOTOMETRIC REDSHIFTS, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Galaxies: evolution, Galaxies: fundamental parameters, Galaxies: general, Astronomy and Astrophysics, Space and Planetary Science, DIGITAL-SKY-SURVEY, 010308 nuclear & particles physics, FORMATION HISTORIES, HUBBLE DEEP FIELD, Order (ring theory), galaxies: fundamental parameters, ENVIRONMENTAL DEPENDENCE, Redshift survey, galaxies: general, Redshift, Galaxy, Bimodality, LUMINOSITY FUNCTION, SPECTROSCOPIC SAMPLE, STELLAR MASS FUNCTION, Cube, galaxies: evolution, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Our goal is to develop a new and reliable statistical method to classify galaxies from large surveys. We probe the reliability of the method by comparing it with a three-dimensional classification cube, using the same set of spectral, photometric and morphological parameters.We applied two different methods of classification to a sample of galaxies extracted from the zCOSMOS redshift survey, in the redshift range 0.5 < z < 1.3. The first method is the combination of three independent classification schemes, while the second method exploits an entirely new approach based on statistical analyses like Principal Component Analysis (PCA) and Unsupervised Fuzzy Partition (UFP) clustering method. The PCA+UFP method has been applied also to a lower redshift sample (z < 0.5), exploiting the same set of data but the spectral ones, replaced by the equivalent width of H$��$. The comparison between the two methods shows fairly good agreement on the definition on the two main clusters, the early-type and the late-type galaxies ones. Our PCA-UFP method of classification is robust, flexible and capable of identifying the two main populations of galaxies as well as the intermediate population. The intermediate galaxy population shows many of the properties of the green valley galaxies, and constitutes a more coherent and homogeneous population. The fairly large redshift range of the studied sample allows us to behold the downsizing effect: galaxies with masses of the order of $3\cdot 10^{10}$ Msun mainly are found in transition from the late type to the early type group at $z>0.5$, while galaxies with lower masses - of the order of $10^{10}$ Msun - are in transition at later epochs; galaxies with $M 5\cdot 10^{10}$ Msun) mostly completed their transition before $z\sim 1$., 16 pages, 14 figures, accepted for publication in A&A

Published
2010

6. Molecular phylogeny of fig wasp pollinators (Agaonidae, Hymenoptera) of Ficus section Galoglychia

Author

Jaco M. Greeff, Simon Van Noort, Emmanuelle Jousselin, J. Christoff Erasmus, Department of Genetics, The University of Texas M.D. Anderson Cancer Center [Houston], South African Museum, Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), and University of Pretoria [South Africa]

Subjects
0106 biological sciences, Ficus, Hymenoptera, [SDV.BID]Life Sciences [q-bio]/Biodiversity, 010603 evolutionary biology, 01 natural sciences, 03 medical and health sciences, MORPHOLOGICAL CLASSIFICATION, Pollinator, FIGUIER, RELATION PLANTE-INSECTE, Genetics, Agaonidae, Molecular Biology, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, FIG TREE, 0303 health sciences, biology, Ecology, AGAONIDAE, biology.organism_classification, Genealogy, FIG WASP POLLINATOR, Molecular phylogenetics, Animal Science and Zoology, HYMENOPTERE, Fig wasp
Abstract

International audience; The obligate mutualism between fig trees and their fig wasp pollinators, together with the general tendency for each host species to be pollinated by one fig wasp species, led to the hypothesis that these two lineages have cospeciated. The pollinators of African figs of section Galoglychia form a diverse group of genera whose species seem to be less constrained to a specific host than other pollinating fig wasp genera. Various authors have suggested remarkably different phylogenetic relationships between the seven genera associated with section Galoglychia. These uncertainties concerning the classification make it difficult to understand the historical patterns of association between these wasps and their hosts. The phylogenetic tree for the pollinators was reconstructed with 28S, COI and ITS2 DNA sequence data and compared with morphological classification of the hosts. Pollinator genera were monophyletic in all analyses. However, the relative position of some genera remains unresolved. Investigation of host−fig association suggests that there have been frequent host jumps between host subsections. This indicates that cospeciation between fig trees and fig wasps is not as stringent as previously assumed. In addition, pollinators of the genus Alfonsiella associated with three host figs (Ficus craterostoma, F. stuhlmannii and F. petersii) are morphologically very similar in South Africa. We investigated the possibility that these pollinators form a complex of species with host-based genetic differentiation. Molecular analyses supported the distinction of the pollinator of F. craterostoma as a good species, but the pollinators of F. stuhlmannii and F. petersii clustered within the same clade, suggesting that these two host species share a single pollinator, Alfonsiella binghami. Based on both molecular data and morphological re-evaluation, a new Alfonsiella species is described, Alfonsiella pipithiensis sp. nov., which is the pollinator of F. craterostoma in southern Africa. A key to both females and males of all described species of Alfonsiella is provided.

Published
2007

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