scholarly journals Intraspecific ecomorphological variations in Poecilia reticulata (Actinopterygii, Cyprinodontiformes): comparing populations of distinct environments

2015 ◽  
Vol 105 (2) ◽  
pp. 217-222 ◽  
Author(s):  
Fábio T. Mise ◽  
Fagner de Souza ◽  
João P. A. Pagotto ◽  
Erivelto Goulart
Keyword(s):  
Poecilia Reticulata ◽  
Principal Component ◽  
Water Current ◽  
Way Of Life ◽  
Morphological Variations ◽  
Current Availability ◽  
Environment Type ◽  
Morphological Variables ◽  
Males And Females ◽  
Morphological Differences

ABSTRACT Morphological variations, according to the principles of ecomorphology, can be related to different aspects of the organism way of life, such as occupation of habitats and feeding behavior. The present study sought to examine the intraspecific variation in two populations of Poecilia reticulata Peters, 1859, that occur in two types of environments, a lotic (Maringá Stream) and a lentic (Jaboti Lake). Due to a marked sexual dimorphism, males and females were analyzed separately. Thus, the proposed hypotheses were that the populations that occur in distinct environments present morphological differences. The morphological variables were obtained using morphometric measurements and the ecomorphological indexes. The data were summarized in a Principal Component Analysis (PCA). A Multivariate Analysis of Variance (Manova) was made to verify significant differences in morphology between the populations. Males and females showed similar ecomorphological patterns according to the environment they occur. In general the population from Maringá Stream had fins with major areas, and the Jaboti Lake population eyes located more dorsally. Additionally, others morphological differences such as wider mouth of the males from Maringá Stream, wider heads on Jaboti Lake females and more protractible mouths on males from Jaboti Lake suggest a set of environmental variables that can possibly influence the ecomorphological patterns of the populations, as the water current, availability of food resources and predation. In summary, the initial hypotheses could be confirmed, evidencing the occurrence of distinct ecomorphotypes in the same species according to the environment type.

Development of sexual characters in the cave shrimp genus Troglocaris (Crustacea: Decapoda: Atyidae) and their applicability in taxonomy

Zootaxa ◽  
2010 ◽  
Vol 2488 (1) ◽  
pp. 1 ◽  
Author(s):  
JURE JUGOVIC ◽  
SIMONA PREVORČNIK ◽  
BORIS SKET
Keyword(s):  
Principal Component Analysis ◽  
Function Analysis ◽  
Principal Component ◽  
Morphological Development ◽  
Closely Related Species ◽  
The Past ◽  
Morphological Studies ◽  
Males And Females ◽  
Morphological Differences ◽  
Age And Sex

In most Atyidae species, male pleopods I–II are specifically shaped in adults. In some species, the same holds true for male pereopods III–V. Due to the age and sex-dependent morphology of these structures, which are presumably used during mating, certain taxonomic mistakes in species diagnoses and identifications have occurred in the past. We studied the morphological development of these appendages in males of the cave shrimp Troglocaris (Troglocaris) planinensis Birštejn, 1948 (= W-Slo phylogroup by Zakšek et al. 2009). In addition, we examined the ontogeny of these structures in males and females from other phylogroups of the subgenus Troglocaris Dormitzer, as well as in the subgenera Spelaeocaris Matjašič, 1956 and Troglocaridella Babić, 1922. Multivariate Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA) on males from the subgenus Troglocaris, confirmed the division of late ontogenetic development into sequential phases. The results indicate that in atyids (1) only mature specimens should be considered when searching for reliable morphological differences between closely related species, (2) pleopods and pereopods show diverse differentiation between taxa, preventing the reliable ascertainment of maturity at all times, (3) body size is often not a reliable indicator of maturity, (4) generally, only very rich samples ensure the presence of the fully mature males that are needed for adequate morphological studies.

Morphological Variation in Fucus Vesiculosus Populations along Temperature and Salinity Gradients in Iceland.

1998 ◽  
Vol 78 (3) ◽  
pp. 985-1001 ◽  
Author(s):  
A. Kalvas ◽  
L. Kautsky
Keyword(s):  
Geographical Area ◽  
Principal Component ◽  
Morphological Type ◽  
Morphological Characters ◽  
Fucus Vesiculosus ◽  
Intermediate Form ◽  
Morphological Variations ◽  
Salinity Gradients ◽  
Significant Difference ◽  
Morphological Differences

Geographical morphological variations in Fucus vesiculosus populations were studied along the coast of Iceland. Principal component analysis (PCA) based on 11 morphological characters clustered the 26 sampling sites into four different morphological types as follows: (1) a morphological type found along the S-SW-W coast; (2) an intermediate form comprising only two populations in the NW; (3) a type found along the N-NE-E-SE coast; and (4) a type found independent of geographical area, in estuaries and at sites influenced by large freshwater outflows. Populations influenced by low salinity had significantly (P ≤ 0·001) shorter thalli, a shorter distance from the holdfast to the oldest dichotomy, smaller fronds, narrower stipes and midrib width compared to the morphology of all other more saline populations. No significant difference in frond width was found between the S-SW-W and the N-NE-E-SE populations. However, significant (P ≤ 0·001) morphological differences between them were observed, the former having shorter thalli, a greater distance from the holdfast to the oldest dichotomy, narrower stipes and smaller midrib width compared to the latter.

scholarly journals Genetic diversity and phylogenetic behavior of some minor legumes

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
James Oludare Agbolade ◽  
Ronke Justina Komolafe
Keyword(s):  
Genetic Diversity ◽  
Principal Component ◽  
Calyx Lobe ◽  
Descriptive Statistics ◽  
International Institute ◽  
Mean Values ◽  
Phylogenetic Relatedness ◽  
Petal Length ◽  
Morphological Differences ◽  
Range Test

Twenty-four accessions of twelve species minor legumes collected from the germplasm unit of the International Institute of Tropical Agriculture Ibadan, Nigeria were evaluated for their genetic diversities and phylogenetic relatedness. The accessions were planted into plots of 5 ridges of 5 meters long, spaced 1 meter apart and replicated three times at the Federal University Oye-Ekiti Teaching and Research Farm. The diversity and the relative phylogeny of the accessions were assessed through their floral morphological differences and the mean values between two accessions were evaluated by descriptive statistics. Principal component analysis was employed to identify the most discriminatory floral morphological traits and the similarities among the 24 accessions were assessed by cluster analysis (CA). Descriptive statistics through Duncan multiple range test adopted revealed genetic diversity and phylogenetic relatedness among the accessions. The first two principal component axes explained 64.66% of the total floral morphological variation. Standard petal length, calyx lobe length and stipule length contributed most of the variations in the legume accession. CA grouped the 24 accessions into six clusters. The study revealed intra-specific similarities and inter-specific floral morphological differences among the studied accessions.

scholarly journals Multivariate analysis of cranial measurements of Cameroon’s Blue Duiker (Cephalophusmonticola Thunberg, 1789)

2020 ◽  
pp. 016-021
Author(s):  
Miantsia Olivier IngFokam ◽  
Félix Meutchieye ◽  
Angwafo PrEvaristus Tsi
Keyword(s):  
Multivariate Analysis ◽  
Principal Component ◽  
High Positive Correlation ◽  
Humid Forest ◽  
Skull Length ◽  
Cranial Measurements ◽  
Significant Difference ◽  
Males And Females ◽  
Blue Duiker ◽  
Basal Length

The blue duiker (Cephalophusmonticola)isexclusively an African wild bovidae. It is a principal source of protein in the African forest zones and contributes in the nutrition of local populations. Fifteen cranial measurements on 60 skulls using the opportunist’s method as from January 2018 to December2018. Descriptive statistic and multivariate analysis were done using SPSS version 21.0software and XLSTAT-Pro version 7.5.2 software. It reveals that, there exist a significant difference between males and females skull (p>0.05): total length of skull 114.32 ± .81 and 121.71 ± 1.77; Palate maximal width 35.24 ± .75 and 44.96 ± 14.80; postorbital apophyses width 23.34 ± 1.11and 36.26 ± 1.79; Palatine length 55.31 ± 1.16 and 66.52 ± 1.86; condyle basal length 96.53 ± 1.26 and 105.43 ± 3.05 for the males and females respectively. We have a high positive correlation between the jugal teeth line length and the total skull length (0.973); between palatine length and the total skull length (0.990) and, between condyle basal length and the total skull length (0.993). The principal component analysis (PCA) enable us to see the level of genetics variabilities of blue duiker through skull measurements. These variables measurement are close together from one to another where there is a high similarity between species. Despite these similarities, the population structure of blue duiker shows three sub-species of blue duiker C1, C2 and C3 found respectively in the agro ecological zones of the Western highlands, Mono-modal humid forest and Bimodal humid forest. These three sub-species varies genetically.

Can morphological characters be used to identify the pond-reared offspring of wild Chinese mitten crabs, Eriocheir sinensis, from different basins?

Crustaceana ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. 957-978
Author(s):  
Xiaodong Jiang ◽  
Xugan Wu ◽  
Haining Wang ◽  
Yuhong Yang ◽  
Yongxu Cheng
Keyword(s):  
Morphological Difference ◽  
Principal Component ◽  
Morphological Characters ◽  
Eriocheir Sinensis ◽  
Stepwise Discriminant Analysis ◽  
Chinese Mitten Crab ◽  
Artificial Culture ◽  
Mitten Crab ◽  
Mitten Crabs ◽  
Morphological Differences

Abstract Although morphology is always used to distinguish wild Chinese mitten crab (Eriocheir sinensis) populations, whether morphology could be used to identify the pond-reared offspring of wild E. sinensis populations has remained unclear. This study was undertaken to examine the morphological difference of wild E. sinensis (G0) from the Yangtze River (YR), Huang River (HR) and Liao River (LR) as well as their pond-reared offspring (G1). The results showed that: (1) The amount of significantly different parameters of three G1 populations was evidently less than that of three G0 populations; (2) G0 and G1 individuals of each population were clearly separated by principal component analysis, furthermore, three G0 populations were clearly separated while three G1 populations were not well distinguished from each other; (3) discrimination accuracy of G1 individuals in stepwise discriminant analysis was obviously lower than that of G1 populations; (4) G0 and G1 populations were clustered into two separate clusters in the cluster analysis. In conclusion, morphological differences between wild E. sinensis populations had disappeared after one generation of artificial culture, and morphology thus probably cannot be used to distinguish the pond-reared offspring originated from three wild E. sinensis populations.

scholarly journals Bone indicators of grasping hands in lizards

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1978 ◽  
Author(s):  
Gabriela Fontanarrosa ◽  
Virginia Abdala
Keyword(s):  
Generalized Linear Models ◽  
Linear Models ◽  
Selective Pressure ◽  
Principal Component ◽  
Functional Trait ◽  
Adaptive Mechanisms ◽  
Morphological Distinction ◽  
Morphological Variables ◽  
Prey Handling ◽  
Functional Setting

Grasping is one of a few adaptive mechanisms that, in conjunction with clinging, hooking, arm swinging, adhering, and flying, allowed for incursion into the arboreal eco-space. Little research has been done that addresses grasping as an enhanced manual ability in non-mammalian tetrapods, with the exception of studies comparing the anatomy of muscle and tendon structure. Previous studies showed that grasping abilities allow exploitation for narrow branch habitats and that this adaptation has clear osteological consequences. The objective of this work is to ascertain the existence of morphometric descriptors in the hand skeleton of lizards related to grasping functionality. A morphological matrix was constructed using 51 morphometric variables in 278 specimens, from 24 genera and 13 families of Squamata. To reduce the dimensions of the dataset and to organize the original variables into a simpler system, three PCAs (Principal Component Analyses) were performed using the subsets of (1) carpal variables, (2) metacarpal variables, and (3) phalanges variables. The variables that demonstrated the most significant contributions to the construction of the PCA synthetic variables were then used in subsequent analyses. To explore which morphological variables better explain the variations in the functional setting, we ranGeneralized Linear Modelsfor the three different sets. This method allows us to model the morphology that enables a particular functional trait. Grasping was considered the only response variable, taking the value of 0 or 1, while the original variables retained by the PCAs were considered predictor variables. Our analyses yielded six variables associated with grasping abilities: two belong to the carpal bones, two belong to the metacarpals and two belong to the phalanges. Grasping in lizards can be performed with hands exhibiting at least two different independently originated combinations of bones. The first is a combination of a highly elongated centrale bone, reduced palmar sesamoid, divergence angles above 90°, and slender metacarpal V and phalanges, such as exhibited byAnolissp. andTropidurussp. The second includes an elongated centrale bone, lack of a palmar sesamoid, divergence angles above 90°, and narrow metacarpal V and phalanges, as exhibited by geckos. Our data suggest that the morphological distinction between graspers and non-graspers is demonstrating the existence of ranges along the morphological continuum within which a new ability is generated. Our results support the hypothesis of the nested origin of grasping abilities within arboreality. Thus, the manifestation of grasping abilities as a response to locomotive selective pressure in the context of narrow-branch eco-spaces could also enable other grasping-dependent biological roles, such as prey handling.

scholarly journals Morphological variability of acorns and its taxonomic significance in Quercus. from Turkey

2015 ◽  
Vol 43 (3) ◽  
pp. 293-299 ◽  
Author(s):  
Y Bakis ◽  
MT Babaç
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variability ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Component Analysis ◽  
Morphological Characters ◽  
Taxonomic Significance ◽  
Morphological Variations ◽  
Quercus Species ◽  
Different Populations

Morphological variations of acorn among and within the groups of Quercus species were studied. A total of 617 acorns belonging to 14 species representing all 3 sections of Quercus L. (Fagaceae) in Turkey were examined in this study. Specimens were collected from 47 different populations over both Anatolian and Thrace part of Turkey. Principal component analysis was used to analyze the morphological characteristics of acorns. Results obtained from this study demonstrate the use of morphological characters in differentiating the taxa of Quercus and Cerris sections studied. Another important finding is the introgression among the acorns of species within Quercus section DOI: http://dx.doi.org/10.3329/bjb.v43i3.21601 Bangladesh J. Bot. 43(3): 293-299, 2014 (December)

scholarly journals A quantitative taxonomic review of Fusichonetes and Tethyochonetes (Chonetidina, Brachiopoda)

2017 ◽  
Vol 91 (6) ◽  
pp. 1296-1305 ◽  
Author(s):  
Hui-ting Wu ◽  
G. R. Shi ◽  
Wei-hong He
Keyword(s):  
Cladistic Analysis ◽  
Species Classification ◽  
Triassic Boundary ◽  
Morphological Variations ◽  
Key Characteristics ◽  
Wide Range ◽  
Kolmogorov Smirnov ◽  
Morphological Variables ◽  
End Members ◽  
Permian Triassic Boundary

AbstractTwo middle Permian (Capitanian) to Early Triassic (Griesbachian) rugosochonetidae brachiopod genera, Fusichonetes Liao in Zhao et al., 1981 and Tethyochonetes Chen et al., 2000, have been regarded as two distinct taxa and used as such for a wide range of discussions including biostratigraphy, paleoecology, paleobiogeography, and the Permian-Triassic boundary mass extinction. However, the supposed morphological distinctions between the two taxa are subtle at best and appear to represent two end members of a continuum of morphological variations. In this study, we applied a range of quantitative and analytical procedures (bivariate plots, Kolmogorov-Smirnov test, categorical principle component analysis, and cladistic analysis) to a dataset of 15 quantified morphological variables, integrating both key external and internal characters, measured from 141 specimens of all well-known Fusichonetes and Tethyochonetes in order to test whether or not these two genera could be distinguished in view of the chosen characters. The results indicate that these two genera are morphologically indistinguishable and that the species classification previously applied to these two genera appears to represent polyphyletic groupings within the genus Fusichonetes. Consequently, Tethyochonetes is concluded to be a junior synonym of Fusichonetes. The diagnosis and key characteristics of Fusichonetes are clarified and refined based on a new suite of well-preserved specimens from the Permian−Triassic Xinmin section in South China.

Distribution, diversity and potential agronomic value of Medicago polymorpha in Sardinia

1995 ◽  
Vol 124 (3) ◽  
pp. 419-426 ◽  
Author(s):  
A. Loi ◽  
C. Porqueddu ◽  
F. Veronesi ◽  
P. S. Cocks
Keyword(s):  
Seed Production ◽  
Principal Component ◽  
Future Research ◽  
Medicago Polymorpha ◽  
Winter Temperatures ◽  
Single Entry ◽  
Morphological Variables ◽  
To Come ◽  
Cluster 2 ◽  
Better Than

SUMMARYThirty-five populations of Medicago polymorpha were collected from throughout Sardinia (Italy) in 1989 with a view to developing pasture species suitable for improving degraded grasslands in the northern Mediterranean basin. Herbage and seed production were compared with the Australian cultivar, Circle Valley, over 2 years at Bonassai, north Sardinia. Regeneration in the 2 years after sowing and seed size were also estimated. All variables were related to collection site parameters using multivariate analysis.Herbage production varied between 2 and 8 t dry matter/ha, and up to 1·5 t/ha of seed was produced. K-means clustering of agronomic and morphological variables indicated that there were two groups present; one similar to variety polymorpha and one to variety vulgaris. There were two other single entry clusters, one of which contained cv. Circle Valley. Principal component analysis of the environmental variables indicated that cluster 1 (vulgaris) was more likely to come from mountainous areas where winter temperatures are low, and cluster 2 (polymorpha) from coastal areas where temperatures are mild. Regeneration of cluster 1 was better than that of cluster 2, which in turn was better than Circle Valley, indicating that populations in cluster 1 are better adapted to the management system imposed at Bonassai.The results indicate that M. polymorpha has considerable potential to improve the grasslands of Sardinia. However, it is unlikely that imported cultivars will be successful, and it seems important that the selection of local populations should continue. Commercial seed production in Sardinia is likely to be a problem, and grazing management under the conditions of communal ownership may have to be reviewed. It is important that future research and development involves farmers and other industry groups.

scholarly journals III. Studies in colour changes of fish. - Part II. —An analysis of the colour patterns of the dab. - Part III. —The action of nicotin and adrenalin in the dab. - Part IV. —The action of caffeine in the dab, and a theory of the control of colour changes in fish

1927 ◽  
Vol 215 (421-430) ◽  
pp. 177-200 ◽  
Keyword(s):  
The Body ◽  
Colour Pattern ◽  
Complete Analysis ◽  
Morphological Variations ◽  
Differential Reaction ◽  
Flat Fish ◽  
Colour Changes ◽  
Morphological Differences ◽  
Colour Patterns ◽  
The Many

In the course of investigations on the action of certain drugs on the colour of the dab, it became increasingly evident that not only should a microscopic examination be made of the results, but that apart from a complete analysis of the colour pattern of the fish, such an examination would be unintelligible. I am not aware that any such analysis has been made of so complicated a colour scheme. Abolin (see List of Papers, p. 198) has analysed the colour pattern of the minnow, and in a previous paper I have pointed out that the barring on the minnow is partly due to physiological differences and partly to morphological variations. Sumner has also given a description of the patterns on certain flat-fish, but his observations were purely macroscopic. The main problem which has presented itself in this field is this :—Do all the chromatophores on the skin expand and contract synchronously and to the same degree? In other words: Are the various colour phases and manifestations of markings due to morphological differences alone? Sumner, as the result of researches carried out on flat-fish, has come to the conclusion that the many variations of colour, pattern and shade cannot be altogether explained by the assumption of a synchronous reaction of all the chromatophores, and that there must be some differential reaction of the chromatophores situated on the markings. Hogben is opposed to this view and thinks that, as “the extent of melanophore expansion in response to the intensity of a uniform background displays a very subtle gradation, it is not unlikely that the effect of a variegated background is simply to reproduce throughout the body a state of melanophore response, which renders more or less apparent a pattern dependent wholly on the numerical distribution of the melanophores in different areas.” In the present research this problem has been approached by a study of the reactions of the dab to uniform backgrounds, to ascertain the extent of the “subtle gradation” and to supply the necessary data for the further discussion of this problem.

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