The Lorenz Curve: A Proper Framework to Define Satisfactory Measures of Symbol Dominance, Symbol Diversity, and Information Entropy

Novel measures of symbol dominance (dC1 and dC2), symbol diversity (DC1 = N (1 - dC1) and DC2 = N (1 - dC2)), and information entropy (HC1 = log2 DC1 and HC2 = log2 DC2) are derived from Lorenz-consistent statistics that I had previously proposed to quantify dominance and diversity in ecology. Here, dC1 refers to the average absolute difference between the relative abundances of dominant and subordinate symbols, with its value being equivalent to the maximum vertical distance from the Lorenz curve to the 45-degree line of equiprobability; dC2 refers to the average absolute difference between all pairs of relative symbol abundances, with its value being equivalent to twice the area between the Lorenz curve and the 45-degree line of equiprobability; N is the number of different symbols or maximum expected diversity. These Lorenz-consistent statistics are compared with statistics based on Shannon's entropy and Rényi's second-order entropy to show that the former have better mathematical behavior than the latter. The use of dC1, DC1, and HC1 is particularly recommended, as only changes in the allocation of relative abundance between dominant (pd > 1/N) and subordinate (ps < 1/N) symbols are of real relevance for probability distributions to achieve the reference distribution (pi = 1/N) or to deviate from it.Universidad de Alcal

Physicochemical and biological changes downstream from a trout farm outlet: comparing 1986 and 2006 sampling surveys

In this investigation we compare the results obtained in the 1986 and 2006 sampling surveys regarding physicochemical and biological changes caused by a trout farm effluent in the upper Tajuña River (Guadalajara, Spain). For this comparison three sampling sites were selected: S-1, placed upstream from the trout farm, was used as a reference station; S-2 and S-3 were respectively placed about 10 m and 1000 m downriver from the trout farm outlet. In both surveys, the concentration of nutrients (ammonia, nitrite, nitrate, phosphate) increased downstream from the trout farm, whereas the concentration of dissolved oxygen decreased. Gammaridae, Heptageniidae, Elmidae, Perlidae, Ancylidae, Hydrobiidae, Glossosomatidae and Sericostomatidae significantly decreased their abundances downstream from the trout farm outlet. On the contrary, Tubificidae, Erpobdellidae, Glossiphoniidae, Planorbidae, Sphaeridae and Chironomidae were clearly favoured. The water quality in ecological terms, as assessed by biotic indices, was markedly reduced, with average scores (ASPT, ASPT', a-BMWQ) showing a better indicator value than total scores (BMWP, BMWP', BMWQ). Shredders and scrapers were the functional feeding groups most severely affected, whereas collectors were clearly favoured. We conclude that the wastewater depuration system of the trout farm must be improved since, during the last twenty years, it has been insufficient to prevent significant alterations in the recipient river.En esta investigación comparamos los resultados obtenidos durante las campañas de muestreo de 1986 y 2006 para los cambios físico-químicos y biológicos producidos por el vertido de una piscifactoría en el tramo alto del río Tajuña (Guadalajara, España). Para ello se seleccionaron tres puntos de muestreo: S-1, aguas arriba de la piscifactoría, sirvió de punto control; S-2 y S-3 se emplazaron, respectivamente, a 10 m y 1000 m aguas abajo del punto de vertido. En ambas campañas, la concentración de nutrientes (amoniaco, nitrito, nitrato, fosfato) aumentó río abajo de la piscifactoría, mientras que la concentración de oxígeno disuelto disminuyó. Gammaridae, Heptageniidae, Elmidae, Perlidae, Ancylidae, Hydrobiidae, Glossosomatidae y Sericostomatidae redujeron significativamente sus abundancias aguas abajo del punto de vertido. Por el contrario, Tubificidae, Erpobdellidae, Glossiphoniidae, Planorbidae, Sphaeridae y Chironomidae fueron claramente favorecidos. La calidad del agua en términos ecológicos, evaluada por medio de índices bióticos, empeoró marcadamente, con las puntuaciones medias (ASPT, ASPT', a-BMWQ) mostrando un mejor valor indicador que las puntuaciones totales (BMWP, BMWP', BMWQ). Desmenuzadores y raspadores fueron los grupos tróficos más severamente afectados, mientras que los recolectores fueron claramente favorecidos. Concluimos que el sistema de depuración de las aguas residuales de la piscifactoría tiene que ser mejorado ya que, durante los últimos veinte años, ha sido insuficiente para prevenir alteraciones significativas en el río receptor

Positive responses of benthic macroinvertebrates to spatial and temporal reductions in water pollution downstream from a trout farm outlet

Inland trout farms can cause important adverse effects on freshwater communities due to the discharge of wastewater effluents into recipient rivers. In this research, responses of benthic macroinvertebrates to diminished water pollution downstream from a trout farm outlet were examined at spatial and temporal scales. Field studies were carried out in the Upper Tajuña River (Central Spain) during the springs of 2007 and 2015. Water pollution decreased, with increasing the downstream distance from the trout farm effluent, and also from 2007 to 2015 as a likely consequence of the lowered annual production of farmed rainbow trout following the 2008 economic recession. Reductions in water pollution resulted in increased concentrations of dissolved oxygen and decreased levels of turbidity and inorganic nutrients (ammonia and phosphate). Benthic macroinvertebrates responded positively to diminished water pollution by decreasing the relative abundance of collector-gatherers (oligochaetes and chironomids) and increasing the relative abundance of shredders and scrapers (ephemeropterans, plecopterans and trichopterans). In addition, values of taxonomic diversity and Biological Monitoring Water Quality biotic indices tended to increase. It is concluded that the wastewater treatment system of the trout farm should be improved to minimize the environmental impact on the recipient river

Respuestas ecológicas de las diatomeas epilíticas y macrófitos acuáticos a la contaminación producida por una piscifactoría en un río español

We examined the ecological responses of epilithic diatoms and aquatic macrophytes to organic pollution and nutrient enrichment caused by a trout farm effluent in the upper Tajuña River (Guadalajara, Spain). Four sampling sites were selected over the study area: one site (S-1) placed upstream from the trout farm was used as a reference station; sampling sites S-2, S-3 and S-4 were set, respectively, about 10, 100 and 1000 metres downriver of the trout farm outlet. The river bottom was mainly stony with cobbles and pebbles at S-1, S-3 and S-4, but at S-2 it was covered by a thick layer of organic sediment. Although some macrophyte species (Apium nodiflorum, Groenlandia densa) were either absent or fewer downstream of the farm, abundance (% coverage) and diversity (number of species) for the aquatic macrophyte community as a whole increased. In contrast, epilithic diatoms were completely absent at S-2, and some species (Diploneis parma, Fragilaria ulna, Gomphonema angustatum, Nitzschia dissipata) were also absent at S-3 and S-4. Indeed, diatom diversity (number of species) was lower at S-3 and S-4 than at S-1. However, diatom abundance (cells/cm2) was higher at S-3 and S-4 than at S-1. Biological indices for diatoms (IBD, TDI) indicated a better water quality at S-1 than at S-3 and S-4, with a clear tendency to improve with distance from the fish farm. In contrast, biological indices of macrophytes (IM, IVAMG) indicated a similar water quality at S-1, S-3 and S-4, but with bad water quality at S-2. We conclude that epilithic diatoms may be more useful than aquatic macrophytes for biological monitoring of fish farm pollution in fluvial ecosystems. However, as historical and seasonal factors may be relevant to understanding the distribution, abundance and diversity of primary producers in running waters, further studies on long-term seasonal changes are needed to improve the use of macrophyte and diatom indices in assessing fish farm pollution.En este trabajo examinamos las respuestas ecológicas de las diatomeas epilíticas y los macrófitos acuáticos a la contaminación orgánica y por nutrientes producida por el vertido de una piscifactoría situada en el tramo alto del río Tajuña (Guadalajara, España). Se seleccionaron cuatro puntos de muestreo a lo largo del área de estudio: uno aguas arriba de la piscifactoría empleado como punto control (S-1); los puntos S-2, S-3 y S-4 se ubicaron a 10, 100 y 1000 m aguas abajo del punto de vertido, respectivamente. El lecho del río era principalmente rocoso, con guijarros y cantos rodados en S-1, S-3 y S-4, pero en S-2 estaba cubierto por una gruesa capa de sedimento orgánico. Pese a que algunas especies de macrófitos (Apium nodiflorum, Groenlandia densa) resultaron ausentes o vieron reducidas sus abundancias aguas abajo del vertido, la abundancia (% covertura) y la diversidad (número de especies) del total de la comunidad de macrófitos acuáticos aumentó. En oposición a esto, las diatomeas epilíticas desaparecieron completamente en S-2, y algunas especies (Diploneis parma, Fragilaria ulna, Gomphonema angustatum, Nitzschia dissipata) también resultaron ausentes en S-3 y S-4. De hecho, la diversidad de diatomeas (número de especies) fue menor en S-3 y S-4 que en S-1. No obstante, la abundancia de diatomeas (células/ cm2) fue superior en S-3 y S-4 que en S-1. Los índices biológicos de diatomeas (IBD, TDI) indicaron una mejor calidad del agua en S-1 que en S-3 y S-4, con una tendencia clara a mejorar con la distancia a la piscifactoría. En contraste, los índices biológicos de macrófitos (IM, IVAM-G) indicaron una calidad del agua similar en S-1, S-3 y S-4, pero con una mala calidad del agua en S-2. Es concluido que las diatomeas epilíticas pueden ser más útiles que los macrofitos acuáticos para la monitorización biológica de la contaminación causada por las piscifactorías en los ecosistemas fluviales. No obstante, debido a que factores históricos y estacionales pueden ser relevantes para entender la distribución, abundancia y diversidad de los productores primarios en las aguas corrientes, estudios posteriores son necesarios para mejorar el uso de los índices de diatomeas y macrófitos para valorar la contaminación producida por las piscifactorías

Genetic diversity and phylogenetic relationships of coevolving symbiont-harboring insect trypanosomatids, and their neotropical dispersal by invader African blowflies (Calliphoridae)

This study is about the inter- and intra-specific genetic diversity of trypanosomatids of the genus Angomonas, and their association with Calliphoridae (blowflies) in Neotropical and Afrotropical regions. Microscopic examination of 3,900 flies of various families, mostly Calliphoridae, revealed that 31% of them harbored trypanosomatids. Small subunit rRNA (SSU rRNA) barcoding showed that Angomonas predominated (46%) over the other common trypanosomatids of blowflies of genera Herpetomonas and Wallacemonas. Among Angomonas spp., A. deanei was much more common than the two-other species, A. desouzai and A. ambiguus. Phylogenetic analyses based on SSU rRNA, glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) and internal transcribed spacer rDNA (ITS rDNA) sequences revealed a marked genetic diversity within A. deanei, which comprised four infraspecific genotypes (Dea1– Dea4), and four corresponding symbiont genotypes (Kcr1–Kcr4). Host and symbiont phylogenies were highly congruent corroborating their co-divergence, consistent with host-symbiont interdependent metabolism and symbiont reduced genomes shaped by a long coevolutionary history. We compared the diversity of Angomonas/symbionts from three genera of blowflies, Lucilia, Chrysomya and Cochliomyia. A. deanei, A. desouzai, and A. ambiguus were found in the three genera of blowflies in South America. In Africa, A. deanei and A. ambiguus were identified in Chrysomya. The absence of A. desouzai in Africa and its presence in Neotropical Cochliomyia and Lucilia suggests parasite spillback of A. desouzai into Chrysomya, which was most likely introduced four decades ago from Africa into the Neotropic. The absence of correlation between parasite diversity and geographic and genetic distances, with identical genotypes of A. deanei found in the Neotropic and Afrotropic, is consistent with disjunct distribution due to the recent human-mediated transoceanic dispersal of Angomonas by Chrysomya. This study provides the most comprehensive data gathered so far on the genetic repertoires of a genus of trypanosomatids found in flies from a wide geographical range.The PROAFRICA, INCT-EPIAMO, and PROSUL programs of CNPq, PNIPB of Capes, and FAPESP (Process 2016/07487-0). CAPEs (PNPD) granted a postdoctoral scholarship to TB.http://www.frontiersin.org/Microbiologyam2018Veterinary Tropical Disease

Hurricanes and Climate: the U.S. CLIVAR Working Group on Hurricanes

While a quantitative climate theory of tropical cyclone formation remains elusive, considerable progress has been made recently in our ability to simulate tropical cyclone climatologies and understand the relationship between climate and tropical cyclone formation. Climate models are now able to simulate a realistic rate of global tropical cyclone formation, although simulation of the Atlantic tropical cyclone climatology remains challenging unless horizontal resolutions finer than 50 km are employed. The idealized experiments of the Hurricane Working Group of U.S. CLIVAR, combined with results from other model simulations, have suggested relationships between tropical cyclone formation rates and climate variables such as mid-tropospheric vertical velocity. Systematic differences are shown between experiments in which only sea surface temperature is increases versus experiments where only atmospheric carbon dioxide is increased, with the carbon dioxide experiments more likely to demonstrate a decrease in numbers. Further experiments are proposed that may improve our understanding of the relationship between climate and tropical cyclone formation, including experiments with two-way interaction between the ocean and the atmosphere and variations in atmospheric aerosols

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

Refined physical parameters for Chariklo's body and rings from stellar occultations observed between 2013 and 2020

Context. The Centaur (10199) Chariklo has the first ring system discovered around a small object. It was first observed using stellar occultation in 2013. Stellar occultations allow sizes and shapes to be determined with kilometre accuracy, and provide the characteristics of the occulting object and its vicinity. Aims. Using stellar occultations observed between 2017 and 2020, our aim is to constrain the physical parameters of Chariklo and its rings. We also determine the structure of the rings, and obtain precise astrometrical positions of Chariklo. Methods. We predicted and organised several observational campaigns of stellar occultations by Chariklo. Occultation light curves were measured from the datasets, from which ingress and egress times, and the ring widths and opacity values were obtained. These measurements, combined with results from previous works, allow us to obtain significant constraints on Chariklo's shape and ring structure. Results. We characterise Chariklo's ring system (C1R and C2R), and obtain radii and pole orientations that are consistent with, but more accurate than, results from previous occultations. We confirm the detection of W-shaped structures within C1R and an evident variation in radial width. The observed width ranges between 4.8 and 9.1 km with a mean value of 6.5 km. One dual observation (visible and red) does not reveal any differences in the C1R opacity profiles, indicating a ring particle size larger than a few microns. The C1R ring eccentricity is found to be smaller than 0.022 (3σ), and its width variations may indicate an eccentricity higher than ~0.005. We fit a tri-axial shape to Chariklo's detections over 11 occultations, and determine that Chariklo is consistent with an ellipsoid with semi-axes of 143.8-1.5+1.4, 135.2-2.8+1.4, and 99.1-2.7+5.4 km. Ultimately, we provided seven astrometric positions at a milliarcsecond accuracy level, based on Gaia EDR3, and use it to improve Chariklo's ephemeris.Fil: Morgado, B.E.. Centre National de la Recherche Scientifique. Observatoire de Paris; Francia. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Sicardy, Bruno. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Braga Ribas, Felipe. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; Brasil. Centre National de la Recherche Scientifique. Observatoire de Paris; Francia. Universidade Tecnologia Federal do Parana; BrasilFil: Desmars, Josselin. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Gomes Júnior, Altair Ramos. Universidade de Sao Paulo; BrasilFil: Bérard, D.. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Leiva, Rodrigo. Universidad de Chile; Chile. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Vieira Martins, Roberto. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Benedetti Rossi, G.. Centre National de la Recherche Scientifique. Observatoire de Paris; Francia. Universidade Federal de Sao Paulo; BrasilFil: Santos Sanz, Pablo. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Camargo, Julio Ignacio Bueno. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Duffard, R.. Universidade Federal do Rio de Janeiro; BrasilFil: Rommel, F.L.. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Assafin, M.. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Boufleur, R.C.. Universidad Nacional de Córdoba; ArgentinaFil: Colas, F.. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Kretlow, Mike. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Beisker, W.. University of North Carolina; Estados UnidosFil: Sfair, Rafael. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Snodgrass, Colin. University of Edinburgh; Reino UnidoFil: Morales, N.. Pontificia Universidad Católica de Chile; Chile. Universidad Católica de Chile; ChileFil: Fernández Valenzuela, E.. Pontificia Universidad Católica de Chile; Chile. Universidad Católica de Chile; ChileFil: Amaral, L.S.. Massachusetts Institute of Technology; Estados UnidosFil: Amarante, A.. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Artola, R.A.. Centre National de la Recherche Scientifique. Observatoire de Paris; FranciaFil: Backes, M.. Universidad Nacional de Córdoba; ArgentinaFil: Bath, K. L.. University of North Carolina; Estados UnidosFil: Bouley, S.. University of St. Andrews; Reino UnidoFil: Garcia Lambas, Diego Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Schneiter, Ernesto Matías. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Ingeniería Económica y Legal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentin

New insights into the evolution of the Trypanosoma cruzi clade provided by a new trypanosome species tightly linked to Neotropical Pteronotus bats and related to an Australian lineage of trypanosomes

Abstract\ud \ud Background\ud Bat trypanosomes are implicated in the evolution of the T. cruzi clade, which harbours most African, European and American trypanosomes from bats and other trypanosomes from African, Australian and American terrestrial mammals, including T. cruzi and T. rangeli, the agents of the American human trypanosomiasis. The diversity of bat trypanosomes globally is still poorly understood, and the common ancestor, geographical origin, and evolution of species within the T. cruzi clade remain largely unresolved.\ud \ud \ud Methods\ud Trypanosome sequences were obtained from cultured parasites and from museum archived liver/blood samples of bats captured from Guatemala (Central America) to the Brazilian Atlantic Coast. Phylogenies were inferred using Small Subunit (SSU) rRNA, glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH), and Spliced Leader (SL) RNA genes.\ud \ud \ud Results\ud Here, we described Trypanosoma wauwau n. sp. from Pteronotus bats (Mormoopidae) placed in the T. cruzi clade, then supporting the bat-seeding hypothesis whereby the common ancestor of this clade likely was a bat trypanosome. T. wauwau was sister to the clade T. spp-Neobats from phyllostomid bats forming an assemblage of trypanosome species exclusively of Noctilionoidea Neotropical bats, which was sister to an Australian clade of trypanosomes from indigenous marsupials and rodents, which possibly evolved from a bat trypanosome. T. wauwau was found in 26.5 % of the Pteronotus bats examined, and phylogeographical analysis evidenced the wide geographical range of this species. To date, this species was not detected in other bats, including those that were sympatric or shared shelters with Pteronotus. T. wauwau did not develop within mammalian cells, and was not infective to Balb/c mice or to triatomine vectors of T. cruzi and T. rangeli.\ud \ud \ud Conclusions\ud \ud Trypanosoma wauwau n. sp. was linked to Pteronotus bats. The positioning of the clade T. wauwau/T.spp-Neobats as the most basal Neotropical bat trypanosomes and closely related to an Australian lineage of trypanosomes provides additional evidence that the T. cruzi clade trypanosomes likely evolved from bats, and were dispersed in bats within and between continents from ancient to unexpectedly recent times.This work was supported by grants from the Brazilian agencies CNPq (PROSUL,\ud PRAFRICA and PROTAX), CAPES (PNIPB and PNPD) and FAPESP. The analysis of\ud bats from Central America, Suriname and Guyana was supported by grant\ud ‘Investissements d’Avenir’ from the Agence Nationale de la Recherche, Canada\ud (ANR-10-LABX-25-01). Archived samples from Brazilian Pteronotus were donated\ud to ACP by VC Tavares, A Césari, PA Rocha, FM Martins, MOG Lopes, CS Bernabé,\ud TG Oliveira, E Gonçalves and M Marcos. We are grateful to many student from\ud USP and researches of other universities for the inestimable help in the\ud fieldworks. We also thanks JA Rosa for the generous contribution with\ud triatomines from the insectary of UNESP-Araraquara, and CE Jared and MM\ud Antoniazzi for the access to electron microscopic facilities of the Institute\ud Butantan, Brazil. Luciana Lima is postdoctoral fellow sponsored by FAPESP, and\ud Oneida Espinosa-Álvarez is recipient of a PhD fellowship from CNPq (PROTAX)