scholarly journals Quantitative Analysis of Morphometric Data of Pre-modern Birds: Phylogenetic Versus Ecological Signal

2021 ◽  
Vol 9 ◽  
Author(s):  
Alyssa Bell ◽  
Jesús Marugán-Lobón ◽  
Guillermo Navalón ◽  
Sergio M. Nebreda ◽  
John DiGuildo ◽  
...  
Keyword(s):  
Strong Relationship ◽  
Original Data ◽  
Significant Degree ◽  
Foraging Strategies ◽  
Morphometric Data ◽  
Ecological Data ◽  
Crown Group ◽  
Avian Evolution ◽  
Terrestrial Vertebrates ◽  
Phylogenetic Signature

Birds are one of the most diverse clades of extant terrestrial vertebrates, a diversity that first arose during the Mesozoic as a multitude of lineages of pre-neornithine (stem) birds appeared but did not survive into the Cenozoic Era. Modern birds (Neornithes) inhabit an extensive array of ecologically distinct habitats and have specific and varied foraging strategies. Likewise, the morphological disparity among Mesozoic lineages appears to underscore a significant degree of ecological diversity, yet attempts to determine lineage-specific ecologies have mainly been limited to superficial narratives. In recent years, numerous studies have used various morphometric proxies to interpret the paleoecology of Mesozoic bird lineages, but largely without evaluating the interplay between ecological and phylogenetic signals. Moreover, most studies of this sort transform the original data into logarithms to control dimensionality, underestimating the biases induced upon such transformations. The goal of this study is to quantitatively address the ecomorphology of crown-group Neornithes using a dense sample of raw forelimb and hindlimb measurements, and to examine if such results can be used to infer the ecologies of Mesozoic bird lineages. To that end, scaling of limb measurements and ecological data from modern birds was assessed statistically using phylogenetic comparative methods, followed by the inclusion of fossil taxa. A strong relationship was recovered between humerus and hindlimb allometric scaling and phylogeny. Our results indicate that while some ecological classes of modern birds can be discriminated from each other, phylogenetic signature can overwhelm ecological signal in morphometric data, potentially limiting the inferences that can be made from ecomorphological studies. Furthermore, we found differential scaling of leg bones among Early Cretaceous enantiornithines and ornithuromorphs, a result hinting that habitat partitioning among different lineages could be a pervasive phenomenon in avian evolution.

scholarly journals Nesting Behaviour of a Neotropical Social Wasp Mischocyttarus saussurei Zikán, 1949 (Hymenoptera, Vespidae)

Sociobiology ◽  
2020 ◽  
Vol 67 (1) ◽  
pp. 121 ◽  
Author(s):  
Lucas Rocha Milani ◽  
Fabio Prezoto ◽  
Mateus Aparecido Clemente ◽  
Patrícia Pereira Gomes ◽  
Marcos Magalhães de Souza
Keyword(s):  
Morphometric Analysis ◽  
Social Wasp ◽  
Minas Gerais ◽  
Southeastern Brazil ◽  
Morphometric Data ◽  
Ecological Data ◽  
Architectural Pattern ◽  
Minas Gerais State ◽  
Nesting Behaviour

Mischocyttarus saussurei nests show a curious architectural pattern which could be related to colony camouflage. Since information on that species is scarce in literature, this study aimed to record ecological data on M. saussurei, as well as morphometric data on its nests. Data was collected at the Parque Estadual do Ibitipoca state park and at the municipalities of Barroso and Inconfidentes, Minas Gerais state, Southeastern Brazil. Seven colonies were located, exclusively in conserved environments. Five nests were dissected for morphometric analysis and for the assessment of the vegetal matter incorporated to comb walls. Nests showed comb cells opening towards the substrate and covered by vegetal layers, in which three families of mosses and three of liverworts could be identified. We deduct that the nests’ morphometry and the incorporation of vegetal layers to the combs are related to the camouflaging of colonies amidst their substrate.

scholarly journals Comparing methods for building trophic spectra of ecological data

2009 ◽  
Vol 67 (3) ◽  
pp. 426-434 ◽  
Author(s):  
Simone Libralato ◽  
Cosimo Solidoro
Keyword(s):  
Systematic Review ◽  
Distribution Function ◽  
Ecosystem Functioning ◽  
Original Data ◽  
Trophic Levels ◽  
Emergent Properties ◽  
Density Functions ◽  
Normal Density ◽  
Density Distribution Function ◽  
Ecological Data

Abstract Libralato, S., and Solidoro, C. 2010. Comparing methods for building trophic spectra of ecological data. – ICES Journal of Marine Science, 67: 426–434. The distribution of biomass, production, and catches over trophic levels (TLs) of the foodweb has been shown theoretically and empirically to provide powerful insights into ecosystem functioning and the effects of fishing. One approach for building trophic spectra of ecological data is based on smoothing original data and assuming zeroes when no values are available for a TL (smoothing-based method). An alternative method is proposed, based on the distribution of ecological data according to density functions (dispersion-based method), and a systematic review of the different alternatives is presented. Six different methods for building trophic spectra, i.e. the smoothing-based and five alternative forms for dispersion-based (using normal, lognormal, and Weibull distributions, also including shifted lognormal and Weibull with zero at TL 2), were applied to ecological properties (i.e. production, biomass, and catches) derived for 24 foodweb models to test their relative performance. The smoothing-based method suffers from the lack of consistency with original data and from unrealistic emergent properties, such as transfer efficiency. The analysis demonstrates the advantages of the dispersion-based method for overcoming these issues and shows, using transfer efficiencies estimated from the models (flow-based estimates) as a reference, that the normal density distribution function performs better.

scholarly journals A Simplified Population-Level Landscape Model Identifying Ecological Risk Drivers of Pesticide Applications, Part One: Case Study for Large Herbivorous Mammals

2021 ◽  
Vol 18 (15) ◽  
pp. 7720
Author(s):  
David Tarazona ◽  
Guillermo Tarazona ◽  
Jose V. Tarazona
Keyword(s):  
Population Dynamics ◽  
Pesticide Exposure ◽  
Population Level ◽  
Guidance Document ◽  
Population Abundance ◽  
Landscape Model ◽  
Ecological Data ◽  
Conceptual Approach ◽  
Terrestrial Vertebrates ◽  
The Impact

Environmental risk assessment is a key process for the authorization of pesticides, and is subjected to continuous challenges and updates. Current approaches are based on standard scenarios and independent substance-crop assessments. This arrangement does not address the complexity of agricultural ecosystems with mammals feeding on different crops. This work presents a simplified model for regulatory use addressing landscape variability, co-exposure to several pesticides, and predicting the effect on population abundance. The focus is on terrestrial vertebrates and the aim is the identification of the key risk drivers impacting on mid-term population dynamics. The model is parameterized for EU assessments according to the European Food Safety Authority (EFSA) Guidance Document, but can be adapted to other regulatory schemes. The conceptual approach includes two modules: (a) the species population dynamics, and (b) the population impact of pesticide exposure. Population dynamics is modelled through daily survival and seasonal reproductions rates; which are modified in case of pesticide exposure. All variables, parameters, and functions can be modified. The model has been calibrated with ecological data for wild rabbits and brown hares and tested for two herbicides, glyphosate and bromoxynil, using validated toxicity data extracted from EFSA assessments. Results demonstrate that the information available for a regulatory assessment, according to current EU information requirements, is sufficient for predicting the impact and possible consequences at population dynamic levels. The model confirms that agroecological parameters play a key role when assessing the effect of pesticide exposure on population abundance. The integration of laboratory toxicity studies with this simplified landscape model allows for the identification of conditions leading to population vulnerability or resilience. An Annex includes a detailed assessment of the model characteristics according to the EFSA scheme on Good Modelling Practice.

scholarly journals Game of Tenure: the role of “hidden” citations on researchers’ ranking in Ecology

2019 ◽  
Author(s):  
Ana Benítez-López ◽  
Luca Santini
Keyword(s):  
Original Data ◽  
Publication Rate ◽  
Ecological Data ◽  
H Index ◽  
Track Record ◽  
Model Parameterization ◽  
Weak Evidence ◽  
Number Of Publications ◽  
Number Of Citations

AimField ecologists and macroecologists often compete for the same grants and academic positions, with the former producing original data that the latter generally use for model parameterization. Original data are usually cited only in the supplementary materials thereby not counting formally as citations, creating an unfair system where field ecologists are routinely under-acknowledged and possibly disadvantaged in the race for funding and positions. Here we explore how the performance of authors contributing ecological data would change if all the citations to their work would be accounted for by bibliometric indicators.LocationWorldwideTime period2008-2017Major taxa studiedHomo sapiens academiaeMethods We collected the track record of >2300 authors from Google Scholar and citation data from 600 papers published in 40 ecology journals, including field-based, conservation, general ecology and macroecology studies. Then we parameterize a simulation that mimics the current publishing system for ecologists and assessed author rankings based on number of citations, H-Index, Impact Factor and number of publications under a scenario where supplementary citations count.Results We found weak evidence for field ecologists being lower ranked than macroecologists or general ecologists, with publication rate being the main predictor of author performance. Accounting for supplementary citations in bibliometrics did not substantially change the current ranking dynamics.Main conclusionsCurrent ranking dynamics are largely unaffected by supplementary citations as they are 10 times less than the number of main text citations. This is exacerbated by the common practice of citing datasets assembled by previous papers instead than the original articles. Nonetheless, researcher performance evaluations should include criteria that better capture authors’ contribution of new, publicly available, data. This could encourage field ecologists to collect and store new data in a systematic manner, thereby mitigating the data patchiness and bias in macroecology studies, and further accelerating the advancement of Ecology.

scholarly journals The earliest equatorial record of frogs from the Late Triassic of Arizona

2019 ◽  
Vol 15 (2) ◽  
pp. 20180922 ◽  
Author(s):  
Michelle R. Stocker ◽  
Sterling J. Nesbitt ◽  
Ben T. Kligman ◽  
Daniel J. Paluh ◽  
Adam D. Marsh ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Equatorial Region ◽  
Late Triassic ◽  
Early Triassic ◽  
High Latitudes ◽  
Crown Group ◽  
Stratigraphic Sequence ◽  
Terrestrial Vertebrates ◽  
Early Mesozoic ◽  
Molecular Phylogenetic

Crown-group frogs (Anura) originated over 200 Ma according to molecular phylogenetic analyses, though only a few fossils from high latitudes chronicle the first approximately 60 Myr of frog evolution and distribution. We report fossils that represent both the first Late Triassic and the earliest equatorial record of Salientia, the group that includes stem and crown-frogs. These small fossils consist of complete and partial ilia with anteriorly directed, elongate and distally hollow iliac blades. These features of these ilia, including the lack of a prominent dorsal protuberance and a shaft that is much longer than the acetabular region, suggest a closer affinity to crown-group Anura than to Early Triassic stem anurans Triadobatrachus from Madagascar and Czatkobatrachus from Poland, both high-latitude records. The new fossils demonstrate that crown anurans may have been present in the Late Triassic equatorial region of Pangea. Furthermore, the presence of Early Jurassic anurans in the same stratigraphic sequence ( Prosalirus bitis from the Kayenta Formation) suggests that anurans survived the climatic aridification of this region in the early Mesozoic. These fossils highlight the importance of the targeted collection of microfossils and provide further evidence for the presence of crown-group representatives of terrestrial vertebrates prior to the end-Triassic extinction.

Trickling filters for upgrading low technology wastewater plants for nitrogen removal

2004 ◽  
Vol 49 (11-12) ◽  
pp. 47-52 ◽  
Author(s):  
P. Pearce
Keyword(s):  
Total Nitrogen ◽  
Nitrogen Removal ◽  
Original Data ◽  
Significant Degree ◽  
Primary Treatment ◽  
Trickling Filter ◽  
Trickling Filters ◽  
Water Region ◽  
Filter Process ◽  
The Uk

Previous work through the 1990s in the Thames Water region in the UK has demonstrated the ability of the trickling filter process to produce fully nitrified effluents, reliably throughout the year. The original data used for the nitrification model derivations have been reanalysed, to investigate the degree of nitrogen removal across the process. Removals of total nitrogen ranging from 0% to over 50% were observed across the trickling filter process and calculated total nitrogen removals of 26-63% were obtained when primary treatment was included. The degree of nitrogen removal and biological denitrification (excluding cellular assimilation) was found to be strongly influenced by BOD load, irrigation velocity and media size. Regression models were produced which gave good predictive relationships for the data ranges used. The models produced worked for filters used with and without a recirculation of effluent nitrate which suggests that a significant degree of nitrification occurred in areas of high heterotroph activity (BOD removal). The simplicity and energy efficiency of the trickling filter process, combined with its capacity for full nitrification and partial denitrification, make the process attractive as a combined process used with pond systems in developing countries where nitrogen removal may be required. Some of these synergies have already been developed with the PETRO® process in South Africa.

scholarly journals PENGARUH KEMAMPUAN KERJA, MOTIVASI KERJA, LINGKUNGAN KERJA DAN BUDAYA ORGANISASI TERHADAP KINERJA PEGAWAI DINAS PENDIDIKAN KABUPATEN BARITO SELATAN

KINDAI ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. 126-136
Author(s):  
Nilawati
Keyword(s):  
Work Performance ◽  
Employee Performance ◽  
Linear Regression Analysis ◽  
Strong Relationship ◽  
Simple Random Sampling ◽  
Total Sample ◽  
Multiple Linear Regression Analysis ◽  
Significant Degree ◽  
Significance Level ◽  
Independent Variables

Abstract: This  research is to analyze the influence, motivation, opportunities, and partial participation on employee performance in the Dinas Pendidikan Kabupaten Barito Selatan. The object of research was employees at the Dinas Pendidikan Kabupaten Barito Selatan. A total of 500 employees. Determination of the sample in this study using simple random sampling, with a sample of 10% of the total sample used for as many as 50 respondents. The independent variables in this study are ability, motivation, opportunity, and discipline, while the required variable is employee work performance. The analysis technique used is multiple linear regression analysis. Transformed regression shows all regression coefficients that are positive, which means all expected independent variables in the model have a direction of change in the direction of the added variables, meaning that the independent variable rises assuming the other independent variables remain free so that the variable rises as well. Based on the analysis results it is concluded that the independent variables collected have a significant effect on the dependent variable. This can be assessed from the results of the t statistical calculation, the t value is greater than t table. The results showed that: Ability (X1) influences employee performance (Y) with a t value of 5.313 greater than t table of 1.701 with a significance level of 0,000. Motivation (X2) affects employee performance (Y) with a t value of 2.780 greater than t table of 1.701 with a significance level of 0.007. Opportunity (X3) influences employee performance (Y) with a t value of 2.116 greater than t table of 1.701 with a significant degree of 0.038. Discipline (X4) has an effect on employee performance (Y) with a t value of 3.922 greater than t table of 1.701 with a significant degree of 0,000. The conversion coefficient is Multiple R of 0.512, this shows that there is a strong relationship between independent variables consisting of ability (X1), motivation (X2), opportunity (X3), and discipline (X4) together to support the achievement employment at Dinas Pendidikan Kabupaten Barito Selatan. This relationship is categorized as strong because of the value   Keyword: Employee's Ability, Motivation, Opportunity, Discipline, and Work Performance.  

Rotational Characteristics of the Green Solar Corona: 1947-1991

1994 ◽  
Vol 144 ◽  
pp. 139-141 ◽  
Author(s):  
J. Rybák ◽  
V. Rušin ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
World Wide ◽  
Rotation Period ◽  
Original Data ◽  
Coronal Emission ◽  
Time Intervals ◽  
Data Set ◽  
The World ◽  
Coronal Emission Line ◽  
Homogeneous Data

AbstractFe XIV 530.3 nm coronal emission line observations have been used for the estimation of the green solar corona rotation. A homogeneous data set, created from measurements of the world-wide coronagraphic network, has been examined with a help of correlation analysis to reveal the averaged synodic rotation period as a function of latitude and time over the epoch from 1947 to 1991.The values of the synodic rotation period obtained for this epoch for the whole range of latitudes and a latitude band ±30° are 27.52±0.12 days and 26.95±0.21 days, resp. A differential rotation of green solar corona, with local period maxima around ±60° and minimum of the rotation period at the equator, was confirmed. No clear cyclic variation of the rotation has been found for examinated epoch but some monotonic trends for some time intervals are presented.A detailed investigation of the original data and their correlation functions has shown that an existence of sufficiently reliable tracers is not evident for the whole set of examinated data. This should be taken into account in future more precise estimations of the green corona rotation period.

Production of New and Revised A.A.V.S.O. Charts

1979 ◽  
Vol 46 ◽  
pp. 368
Author(s):  
Clinton B. Ford
Keyword(s):  
Variable Star ◽  
Standard Form ◽  
Original Data ◽  
University Of Pennsylvania ◽  
Standard Format ◽  
Additional Information ◽  
The Gift ◽  
The University

A “new charts program” for the Americal Association of Variable Star Observers was instigated in 1966 via the gift to the Association of the complete variable star observing records, charts, photographs, etc. of the late Prof. Charles P. Olivier of the University of Pennsylvania (USA). Adequate material covering about 60 variables, not previously charted by the AAVSO, was included in this original data, and was suitably charted in reproducible standard format.Since 1966, much additional information has been assembled from other sources, three Catalogs have been issued which list the new or revised charts produced, and which specify how copies of same may be obtained. The latest such Catalog is dated June 1978, and lists 670 different charts covering a total of 611 variables none of which was charted in reproducible standard form previous to 1966.

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