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Steele, Matthew. "Determining Oxygen Abundance vs. Age and Iron Abundance in Halo Field Dwarfs". Bowling Green State University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1120666230.
Pełny tekst źródłaDEMEIO, JULIAN LAWRENCE. "Abundance of rational points". Doctoral thesis, Scuola Normale Superiore, 2021. http://hdl.handle.net/11384/109444.
Pełny tekst źródłaJonas, Seth H. "Aluminum-26 : an abundance mechanism". Honors in the Major Thesis, University of Central Florida, 2001. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/226.
Pełny tekst źródłaBachelors
Arts and Sciences
Physics
Stehle, Matthias. "Abundance Tomography of Type Ia Supernovae". Diss., lmu, 2004. http://nbn-resolving.de/urn:nbn:de:bvb:19-32721.
Pełny tekst źródłaTsamis, Ionnis. "Heavy element abundance in ionized nebulae". Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270150.
Pełny tekst źródłaAkerman, Christopher John. "Chemical abundance studies, near and far". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613697.
Pełny tekst źródłaArmstrong, David John. "On the abundance of circumbinary exoplanets". Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/72676/.
Pełny tekst źródłaMomal, Raphaëlle. "Network inference from incomplete abundance data Accounting for missing actors in interaction network inference from abundance data Tree‐based inference of species interaction networks from abundance data". Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASM017.
Pełny tekst źródłaNetworks are tools used to represent species relationships in microbiology and ecology. Gaussian Graphical Models provide with a mathematical framework for the inference of conditional dependency networks, which allow for a clear separation of direct and indirect effects. However observed data are often discrete counts and the inference cannot be directly performed with this model. This work develops a methodology for network inference from species observed abundances. The method relies on specific algebraic properties of spanning tree structures to perform an efficient and complete exploration of the space of spanning trees. The inference takes place in a latent space of the observed counts.Then, observed abundances are likely to depend on unmeasured actors (e.g. species or covariate). This results in spurious edges in the marginal network between the species linked to the latter in the complete network, causing inaccurate further analysis. The second objective of this work is to account for missing actors during network inference. To do so we adopt a variational approach yielding valuable insights about the missing actors
Dockendorf, Kevin J. "Relationships between zooplankton abundance and age-0 black crappie abundance and size at three productive Florida lakes". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000523.
Pełny tekst źródłaMcInnes, AM, DG Allan i G. Malan. "Key sites for the conservation of waterbirds (Aves) in Durban Bay, South Africa". Durban Museum Novitates, 2005. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001003.
Pełny tekst źródłaLabuschagne, K., LJ Gerber, I. Espie i S. Carpenter. "Culicoides biting midges at the National Zoological Gardens of South Africa". Onderstepoort Journal of Veterinary Research, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001257.
Pełny tekst źródłaBrewer, Andrew M. "Interactions between demographic rates, population density and the environment : the spatial structure of the range of the holly leaf-miner". Thesis, University of Sheffield, 2001. http://etheses.whiterose.ac.uk/14830/.
Pełny tekst źródłaFriesen, Trevor. "Effects of food abundance and temperature on growth, survival, development and abundance of larval and juvenile smallmouth bass". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ33299.pdf.
Pełny tekst źródłaSullivan, Madsen Paul. "Effects of and Influences on Microbial Populations of Missouri Maize Fields". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7706.
Pełny tekst źródłaTemple, Victoria. "Creating health and abundance with complementary currencies". [Denver, Colo.] : Regis University, 2005. http://165.236.235.140/lib/vtemple2005.pdf.
Pełny tekst źródłaBenisty, Hannah 1986. "Post-transcriptional determinants of RAS protein abundance". Doctoral thesis, Universitat Pompeu Fabra, 2019. http://hdl.handle.net/10803/668206.
Pełny tekst źródłaEls oncogens KRAS, NRAS i HRAS estan mutats en un terç dels càncers en humans on hi exhibeixen patrons de mutació diferents. Un possible factor que contribueix a aquest biaix de mutació és la variació dels nivells d'expressió de RAS. En aquesta tesi investigo els elements determinants de l'abundància de la proteïna RAS. Primer, examino si el biaix de codó entre els gens RAS i entre gens d'altres famílies implicades en càncer contribueix a les diferències d'expressió, en funció del context cel·lular. Així mateix, descric un programa d'expressió de tRNA que facilita la traducció d'oncogens en cèl·lules proliferatives. En segon lloc, investigo per què mutants oncogènics de RAS tenen una abundància de proteïna més elevada que la RAS salvatge. Així mateix, estudio els mecanismes subjacents responsables d'aquesta variació i més concretament el paper de les interaccions de RAS amb altres proteïnes en la regulació de la seva abundància. Així doncs, aquesta tesi estudia la possible rellevància dels mecanismes de síntesi i degradació de la proteïna RAS en els patrons de mutació en càncer.
Harris, Danielle V. "Estimating whale abundance using sparse hydrophone arrays". Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3463.
Pełny tekst źródłaBrandejsová, Jana. "Abundance včelstev v krajině a úživnost katastru". Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-260588.
Pełny tekst źródłaTracey, John Paul. "Assessing estimators of feral goat (Capra hircus) abundance". Connect to this title online, 2004. http://cicada.canberra.edu.au/public/adt-AUC20050708.103427/.
Pełny tekst źródłaVradenburg, John. "Distribution and abundance of anurans in southeast Missouri". Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4258.
Pełny tekst źródłaThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 10, 2007) Includes bibliographical references.
Tracey, John Paul, i n/a. "Assessing estimators of feral goat (Capra hircus) abundance". University of Canberra. Resource, Environmental & Heritage Management, 2004. http://erl.canberra.edu.au./public/adt-AUC20050708.103427.
Pełny tekst źródłaBilodeau-Goeseels, Sylvie. "Changes in RNA abundance in early bovine embryos". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq20726.pdf.
Pełny tekst źródłaEcke, Frauke. "Effects of landscape patterns on small mammal abundance". Doctoral thesis, Luleå, 2003. http://epubl.luth.se/1402-1544/2003/30/index.html.
Pełny tekst źródłaHansteen, Anja Pandora Ulsom. "Oil Abundance, Ethnic Minority Rule, and Civil War". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for samfunnsøkonomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23064.
Pełny tekst źródłaChandramohan, Preethi. "Causal relationships between sulphur emissions and pathogen abundance". Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525131.
Pełny tekst źródłaGardner, M. J. "Circadian rhythms in transcript abundance in Arabidopsis thaliana". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599310.
Pełny tekst źródłaWaring, Paul. "Abundance and diversity of moths in woodland habitats". Thesis, Oxford Brookes University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277095.
Pełny tekst źródłaMaudsley, Martin J. "Regional differences in the abundance of cereal aphids". Thesis, University of East Anglia, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359262.
Pełny tekst źródłaAl-Fahmi, Mohammed M. "Controls on fracture abundance in gently deformed carbonates". Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:74e221c4-6b37-46a5-bba8-7aaa458bed92.
Pełny tekst źródłaKrahmer, Johanna. "Circadian abundance and modification of proteins in Arabidopsis". Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/15969.
Pełny tekst źródłaKirat, Yassine. "Economic and environmental impacts of natural resources abundance". Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01E056.
Pełny tekst źródłaThis thesis examines how societies use and sustain the natural resources that fundamentally shape human well-being, the environment and the economy. The links between economic prosperity, resources and environmental preservation are complex and diverse. This implies that, if all dimensions are not taken into account in public policy making, any progress in achieving objectives in these areas can be hindered by undesirable outcomes. A key issue in development studies is how natural resource wealth affects long-term economic growth. In order to address this question, the first chapter examines the impact of non-conventional resource development on the US manufacturing sector over the period 1997-2013. In the same veine, chapter 3 examines the impact of abundant natural resources on the economy by exploiting the volatility channel of natural resources rent on a panel of 103 countries between 1985-2014. Moreover, the extraction and processing of natural resources are often energy-intensive activities that involve large-scale ecosystem alterations. Chapter 2 of the thesis investigates the impact of natural resource abundance on CO2 intensity in developed countries over the period 1995-2014
Gera, Geetanjali. "Motor abundance contributes to resolve multiple task constraints". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 109 p, 2009. http://proquest.umi.com/pqdweb?did=1885754581&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Pełny tekst źródłaRitchey, Adam M. "The Abundance of Boron in Diffuse Interstellar Clouds". Connect to full text in OhioLINK ETD Center, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1250896589.
Pełny tekst źródłaTypescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Physics." Bibliography: leaves 113-121.
Dennis, Emily Beth. "Development of statistical methods for monitoring insect abundance". Thesis, University of Kent, 2015. https://kar.kent.ac.uk/49079/.
Pełny tekst źródłaHolt, Alison R. "Positive interspecific abundance occupancy relationships : a test of mechanisms". Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246979.
Pełny tekst źródłaPALLA, MARCO. "Cosmic Chemical and Dust Evolution". Doctoral thesis, Università degli Studi di Trieste, 2022. http://hdl.handle.net/11368/3014976.
Pełny tekst źródłaIn this Thesis, we investigate the chemical and dust evolution of the different galactic environments we encounter during the cosmic history, from the high-redshift Universe to the Milky Way. The study of the evolution of galaxies is performed by means of detailed chemical evolution models that predict the abundances of single chemical elements in the interstellar medium as well as the condensation into dust of the chemical elements. In the first part of the Thesis, we concentrate on the study of moderate to high-redshift systems. We start focusing on high-redshift starburst galaxies, whose extreme conditions pose questions on the universality of the initial mass function (IMF) as well as on the processes regulating the ISM dust. For these reasons, we test the the impact of the IMF shape on high-redshift environments by applying the so-called Integrated Galactic IMF (IGIMF) theory in models specifically suited for starburst galaxies. In this way, we look at the interplay between the IMF and dust processes in shaping the observed gas abundance patterns as well as global dust quantities. This analysis highlights the degenerate effect of the IGIMF and dust on abundance patterns and suggests that the IGIMF can explain the dust masses observed in some high-redshift star forming objects. To get a more complete picture about dust through cosmic evolution, we also investigate how dust quantities evolve at larger volume scales. To this aim, we present a novel method to compute the redshift evolution of dust mass in galaxy clusters. This is done by integrating the predictions of chemical and dust evolution models for individual galaxies over the galaxy cluster luminosity function (LF), assuming suitable cosmological scenarios for the LF evolution. By applying this method, we reproduce the dust amounts observed in low and intermediate-redshift galaxy clusters and we answer to some questions about dust in cluster. In particular, we find that spiral galaxies are the most important dust producers within clusters and that galactic ejecta can account alone for the observed intracluster dust. In the second part of the Thesis, instead, we focus on study of the local Universe and in particular of the MW Galaxy. We start investigating the evolution of the MW thick and thin discs by comparing MW models with recent survey data. In particular, we discuss the formation of abundance gradients in the MW and the main physical parameters influencing this process, concluding that inside-out disc formation should act together with radial gas flows and variable efficiency of star formation. Moreover, we suggest that to reproduce the observed [α/Fe] dichotomy/bimodality (i.e., the presence of two distinct data sequences in the [α/Fe] vs. [Fe/H] diagram) at different Galactocentric distances, one should assume a prolonged gap between the formation of the thick and thin discs and a chemically enriched gas accretion in the innermost thin disc. Finally, we study the impact of different Type Ia SN yields on the evolution of Fe-peak elements in our Galaxy. To this aim, we apply to our chemical models for the MW a large compilation of Type Ia SN yields from the recent literature, sampling different explosion mechanisms. The obtained results are compared with those obtained with classical Type Ia SN prescriptions adopted in previous studies. In addition, we allow combinations of of Type Ia SN yields from different progenitor classes to assess their role in terms of the chemical enrichment. We find that the chemical abundance patterns strongly depend not only on the explosion mechanism but also on other conditions. Moreover, the comparison with the observed abundance trends suggests that a combination of different classes of explosion is necessary to reproduce the data.
Yimingniyazi, Wuernisha. "Relic abundance of WIMPs in non-standard cosmological scenarios". [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=985383542.
Pełny tekst źródłaAmbroso, Stefano. "Distribution patterns and abundance of Antarctic pristine benthic communities". Doctoral thesis, Universitat Politècnica de Catalunya, 2021. http://hdl.handle.net/10803/671472.
Pełny tekst źródłaEl conocimiento de la abundancia, los patrones de distribución y la ecología de población de la biodiversidad bentónica antártica ha aumentado considerablemente durante las últimas décadas. La biodiversidad bentónica marina antártica se ha muestreado principalmente en áreas cercanas a las estaciones de investigación y principalmente a poca profundidad desde hace más de 100 años utilizando una variedad de métodos de muestreo, incluidos trineos o redes de arrastre bentónicos, cada uno de los cuales se dirige a una comunidad o hábitat en particular. Los recientes avances tecnológicos y una mayor disponibilidad de vehículos operados a distancia (ROV), sumergibles tripulados y aparatos de muestreo equipados con videocámara han aumentado significativamente la accesibilidad a las plataformas continentales, taludes continentales, cañones submarinos y montañas submarinas, lo que permite la observación directa y el estudio cuantitativo de comunidades megabentónicas sin ningún impacto en la comunidad misma. Debido al alto coste y la compleja logística de estos muestreos, particularmente en la Antártida, los estudios que se generan a menudo se limitan a un solo método de muestreo biológico. Los resultados de los estudios de biodiversidad se utilizan para una variedad de propósitos, que incluyen taxonomía, ecología trófica, tasas de crecimiento, ecología reproductiva, evaluaciones de impacto ambiental y modelos predictivos, todos los cuales sustentan la gestión adecuada de los recursos marinos. Sin embargo, se desconoce la generalidad de los patrones de biodiversidad marina que se pueden identificar entre los diferentes métodos de muestreo. Esta es una de las razones por las que se necesitan más estudios comparativos para comprender mejor los patrones y procesos de los ecosistemas en las regiones antárticas en un contexto de escenario de cambio climático. Las principales regiones de la plataforma antártica parecen estar experimentando un cambio climático rápido, como el calentamiento en la Península Antártica en las últimas décadas. Dicho cambio climático afectará a los ecosistemas bentónicos a través de cambios en el acoplamiento bento-pelágico. Para estos motivos esta tesis tiene como objetivo general comprender la distribución y el papel ecológico que tienen los organismos bentónicos sobre el ecosistema bentónico de la plataforma continental antártica. Esta tesis incluye cuatro capítulos En el primer capítulo se investigan las asociaciones de ofiuras en términos de patrones de distribución y diversidad en tres regímenes ambientales y profundidades diferentes en la Península Antártica. En el segundo capítulo se evalúa el estado de salud de las poplaciones de gorgonias antárticas en un área prístina y remota en la parte más meridional de la plataforma continental del mar de Weddell. En el tercer capítulo se compara el rendimiento de dos artes de muestreo mediante la evaluación de datos cuantitativos en la plataforma continental de tres regiones oceanográficamente muy distintas en la Península Antártica. Finalmente, en el cuarto capítulo se trata de entender la forma en que una población de gorgonias afecta la diversidad de las especies de megafauna asociadas, caracterizando conjuntamente dos poblaciones de gorgonias que habitan en dos plataformas continentales muy diferentes.
Ward, Richard Miles Peary. "Behavioral responses of lynx to declining snowshoe hare abundance". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25065.
Pełny tekst źródłaScience, Faculty of
Zoology, Department of
Graduate
Tzaras, Aspasia. "The factors controlling heterotrophic flagellate abundance in temperate lakes". Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/10361.
Pełny tekst źródłaSimpson, Jeffrey David. "Stellar elemental abundance determination using a Fabry-Pérot Interferometer". Thesis, University of Canterbury. Department of Physics and Astronomy, 2009. http://hdl.handle.net/10092/2684.
Pełny tekst źródłaDestun, Krystofer J. "Mapping stream fish distribution and abundance from riparian vegetation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ35882.pdf.
Pełny tekst źródłaYang, Jeng-Feng. "Motor learning and adaptation the role of motor abundance /". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 216 p, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3247585.
Pełny tekst źródłaJensen, Adam G. "Updated interstellar abundance studies and implications for dust models". Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3256457.
Pełny tekst źródłaWhite, T. C. R. White T. C. R. "Role of nitrogen in limiting the abundance of animals /". Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09ACD/09acdt588.pdf.
Pełny tekst źródłaCopy of his monograph "The inadequate environment : nitrogen and the abundance of animals" in back pocket. Includes bibliographic references.
Nishioka, Shuichiro. "Technology, productivity and knowledge in the factor abundance model". Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3273684.
Pełny tekst źródłaJohansson, Ulf. "Stream channelization effects on fish abundance and species composition". Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97292.
Pełny tekst źródłaMorin, Antoine. "Estimation and prediction of black fly abundance and productivity". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75447.
Pełny tekst źródłaFeldman, Richard. "Toward a theory of abundance at large spatial scales". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104707.
Pełny tekst źródłaL'écologie est l'étude de la diversité, des distributions et des abondances des organismes vivants. Les avancées technologiques récentes couplées à une expansion des objets de recherche ont permis à une étude approfondie de la variation de ces deux premières propriétés sur de très grandes échelles spatiales. Les variations en abondance sont, quant à elles, peu documentées aux grandes échelles spatiales et les développements théoriques correspondant restent limités. Il existe pourtant un pattern prévalent : une espèce donnée est généralement abondante dans une partie extrêmement réduite de sa zone géographique et rare partout ailleurs. Cette observation est aujourd'hui communément expliquée par une variation environnementale sous-jacente. Cette thèse s'appuie sur des approches à la fois empiriques et expérimentales, statistiques et théoriques pour tester le type de variation environnementale ainsi que les interactions entre environnement et compétition interspécifique pouvant générer les variations spatiales en abondances observées. Il est montré que présence-absence et abondance sont affectées par des facteurs environnementaux distincts. Il apparaît en outre que l'effet de la compétition interspécifique dépend des différences de niches entre espèces et module l'impact de l'environnement sur l'abondance en modifiant des coûts et bénéfices relatifs des différentes stratégies d'acquisition des ressources. Finalement, la possibilité de prédire les réponses aux changements climatiques grâce aux données d'abondance et à des modèles statistiques minimisant le bruit inhérent à ce type de données est démontrée. Pour autant, une véritable théorie des distributions d'abondance reste à développer. Le nombre, et a fortiori l'identité, des gradients environnements affectant les abondances à grande échelle spatiale sont encore mal connus. Un effort de recherche considérable est ainsi nécessaire pour améliorer la compréhension du lien entre phénomènes locaux, dont l'interaction entre environnement, traits, comportement et compétition, et patterns à grandes échelles. Par ailleurs, l'unification entre approches basées sur la dispersion, négligeant les différences de niches, avec la théorie actuelle doit encore être accomplie pour qu'une véritable théorie générale des dynamiques macro-évolutive et patterns macro-écologiques puisse voir le jour.
Baldridge, Elita. "A data-intensive assessment of the species-abundance distribution". Thesis, Utah State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3700756.
Pełny tekst źródłaThe hollow curve species abundance distribution describes the pattern of large numbers of rare species and a small number of common species in a community. The species abundance distribution is one of the most ubiquitous patterns in nature and many models have been proposed to explain the mechanisms that generate this pattern. While there have been numerous comparisons of species abundance distribution models, most of these comparisons only use a small subset of available models, focus on a single ecosystem or taxonomic group, and fail to use the most appropriate statistical methods. This makes it difficult to draw general conclusions about which, if any, models provide the best empirical fit to species abundance distributions. I compiled data from the literature to significantly expand the available data for underrepresented taxonomic groups, and combined this with other macroecological datasets to perform comprehensive model comparisons for the species abundance distribution. A multiple model comparison showed that most available models for the species abundance distribution fit the data equivalently well across a diverse array of ecosystems and taxonomic groups. In addition, a targeted comparison of the species abundance distribution predicted by a major ecological theory, the unified neutral theory of biodiversity (neutral theory), against a non-neutral model of species abundance, demonstrates that it is difficult to distinguish between these two classes of theory based on patterns in the species abundance distribution. In concert, these studies call into question the potential for using the species abundance distribution to infer the processes operating in ecological systems.