scholarly journals Bayesian and Multivariate Analyses of combined molecular and morphological data in Linum austriacum (Linaceae) populations: Evidence for infraspecific taxonomic groups

2015 ◽  
Vol 16 (2) ◽  
pp. 179-187 ◽  
Author(s):  
FATIMA AFSHAR
Keyword(s):  
Multivariate Analyses ◽  
Morphological Data ◽  
Taxonomic Groups

Origin of Symphyotrichum anticostense (Asteraceae: Astereae), an endemic, high polyploid species of the Gulf of St. Lawrence region, based on morphological and nrDNA evidence

Botany ◽  
2022 ◽  
Author(s):  
Jamil Vaezi ◽  
Luc Brouillet
Keyword(s):  
New Brunswick ◽  
Multivariate Analyses ◽  
Sequence Data ◽  
Morphological Data ◽  
Its Sequence ◽  
Long Distance ◽  
High Polyploid ◽  
Geographic Origins ◽  
Anticosti Island ◽  
Rare Endemic

Symphyotrichum anticostense (Fernald) G.L.Nesom (Asteraceae: Astereae), a rare endemic of the Gulf of St. Lawrence region is a high allopolyploid (2n=10x=80). It has been hypothesized to be derived from the hybrid between tetraploid (2n=4x=32) individuals of S. boreale (Torr. & A.Gray) Löve & Löve and the hexaploid (2n=6x=48) S. novi-belgii (L.) G.L.Nesom. We investigated this hypothesis using morphological and molecular ITS-sequence data, and we tried to determine the potentially geographic origins of the taxon. Univariate morphological analyses show that 67.5% of the S. anticostense characters are parent-like, 43.5% from S. novi-belgii and 13% from S. boreale, the remainder not differing statistically from either parent; 23.5% are intermediate; and 9% transgressive. Multivariate analyses show that S. anticostense is intermediate between its putative parents. The molecular results support the morphological data, but due to the insufficient resolution among ribotypes on the tree, a more rapidly evolving marker will be needed to ascertain more reliably the origin of S. anticostense. Besides the hypothesis of genetic drift and allele fixation following long-distance dispersals, at least three independent geographic origins may be suggested for S. anticostense; Anticosti Island, Lake St. John, and Gaspé Peninsula-New Brunswick-Maine.

scholarly journals The role of preservation on the quantification of morphology and patterns of disparity within Paleozoic echinoderms

2017 ◽  
Vol 91 (4) ◽  
pp. 618-632 ◽  
Author(s):  
Bradley Deline ◽  
James R. Thomka
Keyword(s):  
Morphological Diversity ◽  
Morphological Data ◽  
Data Sets ◽  
Relative Distribution ◽  
Depositional Facies ◽  
Stratigraphic Sequence ◽  
Secular Changes ◽  
Significant Bias ◽  
Taxonomic Groups

AbstractThe loss of information resulting from taphonomic degradation could represent a significant bias in the study of morphological diversity. This potential bias is even more concerning given the uneven effect of taphonomy across taxonomic groups, depositional facies, and stratigraphic successions and in response to secular changes through the Phanerozoic. The effect of taphonomic degradation is examined using character-based morphological data sets describing disparity in Paleozoic crinoids and blastozoans. Characters were sequentially excluded from the analyses following progressive taphonomic loss to determine how morphologic metrics, such as the relative distribution of taxa in morphospace and partial disparity, changed with increasing taphonomic alteration. Blastozoans showed very little change in these metrics with decreasing preservational quality, which is a result of characters that create distance in morphospace being recognizable in isolated plates. The opposite result is present in crinoids as the characters that are important in structuring the morphospace require intact modules (i.e., the calyx) to accurately assess. Temporal and stratigraphic trends produced encouraging results in that patterns could be largely recovered even with exaggerated taphonomic biases. However, certain parts of a stratigraphic sequence should be avoided and morphological outliers could potentially play a larger role through time, though both of these biases can be easily identified and avoided. The methods presented in this study provide a way to assess potential taphonomic biases in character-based studies of morphological diversity.

Phenetic affinities of males of the army ant genus Dorylus (Hymenoptera: Formicidae: Dorylinae)

1982 ◽  
Vol 60 (11) ◽  
pp. 2652-2658 ◽  
Author(s):  
David Barr ◽  
William H. Gotwald Jr.
Keyword(s):  
Multivariate Analyses ◽  
Single Species ◽  
Morphological Data ◽  
Taxonomic Structure ◽  
Old World ◽  
Army Ant

Multivariate analyses of males of 25 species of the Old World army ant genus Dorylus were used to investigate taxonomic structure inherent in the morphological data gathered. Results were compared both with the current subgeneric classification of this genus and with results from a similar study on the major workers. Males are phenetically more divergent than major workers. The subgenera Rhogmus, Alaopone, and Typhlopone appear deserving of continued individual status, but species of Anomma and Dorylus (s.s.) form one diverse taxon. Although the single species of Dichthadia is relatively distinctive in this study, a conservative classification would place it with species of Dorylus (s.s.).

scholarly journals Ultrastructural, Cytochemical, and Comparative Genomic Evidence of Peroxisomes in Three Genera of Pathogenic Free-Living Amoebae, Including the First Morphological Data for the Presence of This Organelle in Heteroloboseans

2020 ◽  
Vol 12 (10) ◽  
pp. 1734-1750
Author(s):  
Arturo González-Robles ◽  
Mónica González-Lázaro ◽  
Anel Edith Lagunes-Guillén ◽  
Maritza Omaña-Molina ◽  
Luis Fernando Lares-Jiménez ◽  
...  
Keyword(s):  
Protein Import ◽  
Acanthamoeba Castellanii ◽  
Morphological Data ◽  
Comparative Genomic ◽  
Reaction Products ◽  
Free Living ◽  
Transmission Electron ◽  
Complete Set ◽  
Taxonomic Groups ◽  
Naegleria Lovaniensis

Abstract Peroxisomes perform various metabolic processes that are primarily related to the elimination of reactive oxygen species and oxidative lipid metabolism. These organelles are present in all major eukaryotic lineages, nevertheless, information regarding the presence of peroxisomes in opportunistic parasitic protozoa is scarce and in many cases it is still unknown whether these organisms have peroxisomes at all. Here, we performed ultrastructural, cytochemical, and bioinformatic studies to investigate the presence of peroxisomes in three genera of free-living amoebae from two different taxonomic groups that are known to cause fatal infections in humans. By transmission electron microscopy, round structures with a granular content limited by a single membrane were observed in Acanthamoeba castellanii, Acanthamoeba griffini, Acanthamoeba polyphaga, Acanthamoeba royreba, Balamuthia mandrillaris (Amoebozoa), and Naegleria fowleri (Heterolobosea). Further confirmation for the presence of peroxisomes was obtained by treating trophozoites in situ with diaminobenzidine and hydrogen peroxide, which showed positive reaction products for the presence of catalase. We then performed comparative genomic analyses to identify predicted peroxin homologues in these organisms. Our results demonstrate that a complete set of peroxins—which are essential for peroxisome biogenesis, proliferation, and protein import—are present in all of these amoebae. Likewise, our in silico analyses allowed us to identify a complete set of peroxins in Naegleria lovaniensis and three novel peroxin homologues in Naegleria gruberi. Thus, our results indicate that peroxisomes are present in these three genera of free-living amoebae and that they have a similar peroxin complement despite belonging to different evolutionary lineages.

A morphology-based phylogenetic analysis of Fasciolariidae (Gastropoda: Buccinoidea)

Zootaxa ◽  
2019 ◽  
Vol 4684 (1) ◽  
pp. 1-65
Author(s):  
DIOGO R. COUTO ◽  
LUIZ R. L. R. SIMONE
Keyword(s):  
Morphological Data ◽  
Phylogenetic Study ◽  
Similar Species ◽  
Molecular Phylogenetic Study ◽  
The Family ◽  
Basal Clade ◽  
Morphological Approach ◽  
Molecular Phylogenetic ◽  
Taxonomic Groups ◽  
The Tropics

Fasciolariids are buccinoid neogastropods and key predators in the tropics and subtropics, comprising more than 500 species in the subfamilies Fasciolariinae, Fusininae and Peristerniinae. Tulip shells, horse-conchs, spindles, etc., have been grouped into heterogeneous combinations of unrelated species, while several generic names have been used to group conchologically similar species. The latest molecular phylogenetic study conflicts with the current circumscription of many genera, and even more so, with the three currently recognized subfamilies. This work is the first morphological approach to the phylogeny of fasciolariids, using a parsimony analysis in TnT of 53 taxa based on 100 characters. This analysis reveals a monophyletic Fasciolariidae, with the genera Dolicholatirus and Teralatirus representing the most basal clade in the family, followed by three nodes that correspond to a fusinine grade, which includes the genus Pseudolatirus (Peristerniinae). A terminal clade groups the peristerniine genera Peristernia and Fusolatirus, fasciolariines and the remaining peristerniines. Although none of these clades correspond to currently accepted taxonomic groups, the latter two clades are corroborated in the most recent multilocus molecular phylogeny. This study supports the utility of morphological data in the recovery of groups, even in the molecular era. 

scholarly journals Diversity Analysis in Rice Using GENSTAT and SPSS Programs

1970 ◽  
Vol 8 (2) ◽  
pp. 14-21
Author(s):  
MM Rahman ◽  
A Ansari ◽  
MM Rashid
Keyword(s):  
Cluster Analysis ◽  
Multivariate Analysis ◽  
Multivariate Analyses ◽  
Breeding Strategy ◽  
Morphological Data ◽  
Physiological Data ◽  
Diversity Analysis ◽  
Rice Cultivars ◽  
Spss Software ◽  
Effective Development

A study was conducted to assess the morpho-physiological divergence among 21 T. Aman rice cultivars at BRRI regional station, Sonagazi, Feni, during July 2008 to December 2008. Data were collected on 13 morphological and 14 physiological traits. Cluster analysis were carried out separately by using two softwares viz. GENSTAT v 5.5 and SPSS v 12.0 where in, both the software divided the cultivars into five clusters in both cases. The resulted clusters seemed to be very similar to some swapping genotypes which indicate that the softwares showed little dissimilarity. When clusterings were carried out using 13 morphological data, multivariate analysis showed five clusters in both GENSTAT and SPSS software with 19.05% swapping genotypes. When multivariate analyses were done with GENSTAT and SPSS softwares based on 14 physiological data, five clusters were also found with 14.29 % swapping genotypes. Of the two programs, GENSTAT appeared to be more reliable than the SPSS program. Inclusion of BR3, BR5, BR11, BR23, BRRI dhan33, BRRI dhan38, BRRI dhan44 and BRRI dhan46 giving emphasis on BRRI dhan33, BRRI dhan38, BRRI dhan44 and BRRI dhan46 is recommended for effective development of a breeding strategy in diallel fashion. Keywords: Clustering; multivariate analysis; rice; transplanted aman. DOI: 10.3329/agric.v8i2.7572 The Agriculturists 8(2): 14-21 (2010)

scholarly journals Comparative Analysis of Mollusc Assemblages from Different Hard Bottom Habitats in the Central Tyrrhenian Sea

Diversity ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 74 ◽  
Author(s):  
Edoardo Casoli ◽  
Andrea Bonifazi ◽  
Giandomenico Ardizzone ◽  
Maria Flavia Gravina ◽  
Giovanni Fulvio Russo ◽  
...  
Keyword(s):  
Trophic Structure ◽  
Multivariate Analyses ◽  
Distribution Patterns ◽  
The Other ◽  
Tyrrhenian Sea ◽  
Coastal Zones ◽  
Habitat Differences ◽  
Molluscan Fauna ◽  
Mollusc Assemblages ◽  
Taxonomic Groups

Composition, trophic structure, and species-substrate relationships of molluscan assemblages inhabiting different hard bottom habitats (Sabellaria alveolata reef, photophilic bottoms, Phyllophora crispa sciaphilic assemblage, and coralligenous bioconstruction) were studied in two different sites of the Tyrrhenian Sea. In particular, molluscs from the Sabellaria alvevolata (Linnaeus, 1767) reef and coralligenous concretion were investigated, testing the hypothesis that bioconstructions increase the diversity and abundance of associated biota compared to the surrounding habitats. A total of 3134 individuals belonging to the classes of Polyplacophora (5 species, 24 individuals), Bivalvia (39 sp., 2734 ind.), and Gastropoda (53 sp., 376 ind.) were identified. These three taxonomic groups showed different distribution patterns in the studied habitats. Multivariate analyses revealed significant inter-habitat differences in the composition of mollusc assemblages, especially between bioconstructions and the other habitats. S. alveolata and coralligenous host the highest rich molluscan fauna when compared to the neighboring hard bottom habitats characterized by photophilic and sciaphilic assemblages. The first ones were dominated by bivalve suspension feeders, mainly represented by sessile and sedentary organisms, which act as bio-constructors, bio-eroders, or simply inhabit the several microhabitats provided by the bioconstructions, while the second ones host a rich molluscan fauna dominated by gastropod grazers and predators. The present study increases the comparative knowledge of molluscan assemblages inhabiting habitats of littoral plans of the Mediterranean Sea, providing pivotal information regarding biodiversity of coastal zones.

Taxonomy of the tribe Triticeae (Poaceae) using various numerical techniques. II. Classification

1978 ◽  
Vol 56 (1) ◽  
pp. 27-56 ◽  
Author(s):  
Bernard R. Baum
Keyword(s):  
Multivariate Analyses ◽  
Genetic Relationships ◽  
Intergeneric Hybrid ◽  
Theory Model ◽  
Morphological Data ◽  
Numerical Techniques ◽  
Maximum Information ◽  
Square Roots ◽  
Morphologic Data ◽  
Tribe Triticeae

The paper reports on a study that consists of various numerical taxonomic analyses of genera of Triticeae aimed at finding intergeneric relationships based on maximum information and proposing a classificatory scheme. The data consist of morphological features, genetic relationships expressed in terms of successful crosses, and relationships assessed from the occurrence of intergeneric hybrid 'genera.' The morphological data were analysed separately in order to find out if they reflect by themselves the relationships between the genera before the data were combined with the information on crosses and on parentages of intergeneric hybrid 'genera.' The morphologic data consist of a set of 35 characters and one of 45 characters, both with equidistant states, and a set of 35 characters with weighted states. The combinations of data (morphology, crosses, and parentages) were effected through the merging of dissimilarity matrices using a few approaches such as squaring of elements of the matrices, adding the squares and taking their averages, and then taking the square roots of these averages. The relationships between the various matrices (original and combined) were assessed with Gower's technique of comparison of multivariate analyses. To find classifications, the various matrices were processed through cluster analyses. Admissible phenograms and admissible classifications were selected on the basis of a set of criteria. Subsequently, the admissible classifications were assessed using Estabrook's information theory model; a best classification was chosen. A new system of Triticeae is presented even though the data indicate clinal relationships among its members.

scholarly journals An investigation into the taxonomy of Dendrelaphis tristis (Daudin, 1803): revalidation of Dipsas schokari (Kuhl, 1820) (Serpentes, Colubridae)

2008 ◽  
Vol 77 (1) ◽  
pp. 33-43 ◽  
Author(s):  
Johan van Rooijen ◽  
Gernot Vogel
Keyword(s):  
Sri Lanka ◽  
Western Ghats ◽  
Multivariate Analyses ◽  
Taxonomic Status ◽  
Distribution Patterns ◽  
Lower Number ◽  
Morphological Data ◽  
Museum Specimens ◽  
South West

The taxonomic status of the colubrid snake Dendrelaphis tristis (Daudin, 1803) was investigated on the basis of morphological data taken from 64 museum specimens. Univariate and multivariate analyses of these data reveal that Dendrelaphis tristis is composed of two species. One of these species agrees with the description of Dipsas schokari Kuhl, 1820 which is revalidated in the combination Dendrelaphis schokari (Kuhl, 1820). The syntypes of D. schokari have been lost and a type for D. tristis has never been deposited in a collection. Neotypes are designated and described for both species in order to stabilize the names. D. schokari differs from D. tristis in having a lower number of ventrals and subcaudals, a larger eye, a shorter vertebral stripe and the absence of a bright interparietal spot. D. tristisand D. schokari exhibit a partially overlapping distribution. D. tristis ranges from Sri Lanka northward through most of India to Myanmar whereas the distribution of D. schokari is restricted to Sri Lanka and South-west India (Western Ghats). Although the two species coexist on Sri Lanka and in South-west India, these species presumably do not occur syntopically as suggested by their distribution patterns and morphology.

scholarly journals Schrödinger’s phenotypes: herbarium specimens show two-dimensional images are both good and (not so) bad sources of morphological data

2020 ◽  
Author(s):  
Leonardo M. Borges ◽  
Victor Candido Reis ◽  
Rafael Izbicki
Keyword(s):  
Large Scale ◽  
Multivariate Analyses ◽  
Morphological Data ◽  
List Type ◽  
Museum Specimens ◽  
Two Dimensional ◽  
Lower Accuracy ◽  
Precision And Accuracy ◽  
Two Dimensional Images

AbstractMuseum specimens are the main source of information on organisms’ morphological features. Although access to this information was commonly limited to researchers able to visit collections, it is now becoming freely available thanks to the digitization of museum specimens. With these images, we will be able to collectively build large-scale morphological datasets, but these will only be useful if the limits to this approach are well-known. To establish these limits, we used two-dimensional images of plant specimens to test the precision and accuracy of image-based data and analyses.To test measurement precision and accuracy, we compared leaf measurements taken from specimens and images of the same specimens. Then we used legacy morphometric datasets to establish differences in the quality of datasets and multivariate analyses between specimens and images. To do so, we compared the multivariate space based on original legacy data to spaces built with datasets simulating image-based data.We found that trait measurements made from images are as precise as those obtained directly from specimens, but as traits diminish in size, the accuracy drops as well. This decrease in accuracy, however, has a very low impact on dataset and analysis quality. The main problem with image-based datasets comes from missing observations due to image resolution or organ overlapping. Missing data lowers the accuracy of datasets and multivariate analyses. Although the effect is not strong, this decrease in accuracy suggests caution is needed when designing morphological research that will rely on digitized specimens.As highlighted by images of plant specimens, 2D images are reliable measurement sources, even though resolution issues lower accuracy for small traits. At the same time, the impossibility of observing particular traits affects the quality of image-based datasets and, thus, of derived analyses. Despite these issues, gathering phenotypic data from two-dimensional images is valid and may support large-scale studies on the morphology and evolution of a wide diversity of organisms.

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