Morphological Variation and Fluctuating Asymmetry Among Insular Populations of the Sleepy Lizard, Trachydosaurus-Rugosus Gray (Squamata, Scincidae)

1991 ◽  
Vol 39 (1) ◽  
pp. 91 ◽  
Author(s):  
S Sarre ◽  
JM Dearn
Keyword(s):  
Fluctuating Asymmetry ◽  
Morphological Characteristics ◽  
South Australia ◽  
Morphological Characters ◽  
Small Population ◽  
Developmental Stability ◽  
Developmental Instability ◽  
Allozyme Electrophoresis ◽  
Genetic Changes ◽  
Island Populations

Morphological characteristics of island populations of the sleepy lizard, Trachydosaurus rugosus, were compared with those of three adjacent mainland populations in South Australia. An analysis of 21 morphological characters revealed greater divergence among the island populations than among those on the mainland. However, in contrast with the findings of an earlier study using allozyme electrophoresis, morphological relationships among populations showed little congruence with the relationships expected from their geographic proximity. Two measures of developmental stability (fluctuating asymmetry and percentage gross abnormalities) varied significantly among the populations. High levels of developmental instability were observed in three of the island populations. It is not possible to rule out environmental causes of the increased developmental instability but it appears more likely that it is caused by genetic drift and inbreeding resulting from small population size. These results suggest that developmental stability may be more useful in monitoring genetic changes in wildlife populations than the conventional method of allozyme electrophoresis.

scholarly journals Fluctuating Asymmetry in Morphological Characteristics of Betula Pendula Roth Leaf under Conditions of Urban Ecosystems: Evaluation of the Multi-Factor Negative Impact

Symmetry ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1317 ◽  
Author(s):  
Elena Shadrina ◽  
Nina Turmukhametova ◽  
Victoria Soldatova ◽  
Yakov Vol'pert ◽  
Irina Korotchenko ◽  
...  
Keyword(s):  
Fluctuating Asymmetry ◽  
Betula Pendula ◽  
Negative Impact ◽  
Morphological Characteristics ◽  
Developmental Stability ◽  
Anthropogenic Load ◽  
Traffic Load ◽  
Anthropogenic Factors ◽  
Betula Pendula Roth ◽  
The Impact

The fluctuating asymmetry (FA) in Betula pendula Roth was estimated as an integrated measure of five morphometric characteristics of a lamina. Samples were collected in seven cities that differ both in climatic conditions, moderately to sharply continental. In total, 33 ecotopes were distinguished with various level of anthropogenic load. The statistical data processing involved correlation, one-way and factorial ANOVA, regression analyses, and principal component analysis (PCA). The impact of 25 climatic and anthropogenic factors on the FA value was considered. In most urban ecotopes, the integrated fluctuating asymmetry (IFA) value was higher than in natural biotopes of the same region. No significant inter-annual differences in IFA values were found. FA dependence on traffic load is noted to be statistically significant. The covariation analysis of IFA, climatic, and anthropogenic variables in various urban ecotopes revealed the impact of three groups of factors that together explain 93% of the variance in environmental parameters. The complex analysis clearly arranged the studied ecotopes by pollution gradient and climatic patterns. The primary effect of the total anthropogenic load on the developmental stability of B. pendula results in an IFA increase. IFA can play a key role in bioindication assessment of environmental quality. The climatic factors have no significant effect on the developmental stability of B. pendula in urban conditions.

scholarly journals Does inbreeding affects developmental stability in Drosophila subobscura populations?

Genetika ◽  
2011 ◽  
Vol 43 (3) ◽  
pp. 639-654
Author(s):  
Zorana Kurbalija-Novicic ◽  
Marina Stamenkovic-Radak ◽  
Gordana Rasic ◽  
Marko Andjelkovic
Keyword(s):  
Fluctuating Asymmetry ◽  
Population Level ◽  
Inbred Lines ◽  
Developmental Stability ◽  
Developmental Instability ◽  
Drosophila Subobscura ◽  
Wing Size ◽  
Knowing That ◽  
Genomic Stress ◽  
Variability Pattern

In the present paper, we focused on the coadaptive aspect of genetic variability at population level and its relation to genomic stress such as inbreeding. The paper evaluates the effects of an experimental reduction of average heterozygosity after fourteen generations of systematic inbreeding in laboratory conditions, on developmental stability in Drosophila subobscura populations from two ecologically and topologically distinct habitats, knowing that they possess a certain degree of genetic differences due to their different evolutionary histories. The aims were to analyze: (i) the variability change of wing size (length and width) among the inbred lines from both populations; (ii) the relations between homozigosity and level of fluctuating asymmetry as a potential measure of developmental instability, in inbred lines originating from two populations. Results for the wing size showed similar between line variability pattern across generations of systematic inbreeding in both populations. The obtained results suggest that variability of fluctuating asymmetry as a measure of developmental instability can not be related to homozygosity due to inbreeding per se, in both experimental populations.

scholarly journals Scutation asymmetries in red-footed tortoise Chelonoidis carbonaria Spix, 1824 (Testudines: Testudinidae)

2020 ◽  
Vol 60 ◽  
pp. e20206039
Author(s):  
Pere M. Parés-Casanova ◽  
Pinzón Brando ◽  
Daniel Caviedes ◽  
Arcesio Salamanca-Carreño
Keyword(s):  
Fluctuating Asymmetry ◽  
Environmental Conditions ◽  
Developmental Stability ◽  
Developmental Instability ◽  
Directional Asymmetry ◽  
Random Perturbations ◽  
Scale Cover ◽  
Potential Sources ◽  
Sources Of Variation ◽  
Preliminary Study

The ability of an individual to withstand random perturbations during its development is considered a good indicator of environmental and genetic stress. A common means of assessing developmental stability is through analysis of fluctuating asymmetry (FA) in bilateral traits. Tortoises, with their large, solid plastron, allow for measurement of body geometry. Their bilateral shell scutes are ideal candidates for asymmetries researches. With this issue in mind we assessed, as a preliminary study, levels of plastron scute asymmetry in a sample of 46 red-footed tortoise Chelonoidis carbonaria from Arauca, N Colombia. We found significative fluctuating asymmetry (FA) but no directional asymmetry, the former not increasing with carapace size and thus indicating that tortoise shells do not become increasingly asymmetrical with age, or in other words, signaling that FA is not being influenced by pholidosis (variability of scale cover mosaic according to the development of the scutes). Asymmetry in plastron shape, although not necessarily apparent at first glance, varied, with gender with males exhibiting higher levels of FA than females. Although we can not identify the potential sources of variation responsible for the observed patterns of developmental instability, we consider this detected form of asymmetry due to unfavorable environmental conditions.

Developmental stability and heterozygosity in chum (Oncorhynchus keta) and pink (Oncorhynchus gorbuscha) salmon

1987 ◽  
Vol 65 (7) ◽  
pp. 1823-1826 ◽  
Author(s):  
T. D. Beacham ◽  
R. E. Withler
Keyword(s):  
Fluctuating Asymmetry ◽  
Chum Salmon ◽  
Pink Salmon ◽  
Morphological Characters ◽  
Developmental Stability ◽  
Oncorhynchus Gorbuscha ◽  
Oncorhynchus Keta ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Gill Raker ◽  
Fin Length

We compared developmental stability as measured by fluctuating asymmetry within individual adults for gill raker and branchiostegal ray number and pectoral and pelvic fin length for three populations of chum salmon (Oncorhynchus keta) and one of pink salmon (Oncorhynchus gorbuscha). There was no association between individual heterozygosity calculated at 10 electrophoretic loci for chum salmon and 13 loci for pink salmon and magnitude of fluctuating asymmetry for the four morphological characters examined. More heterozygous individuals were not less asymmetrical, and thus our results provide no evidence to suggest that increased heterozygosity results in an increased canalization of morphology during development and growth.

scholarly journals A STUDY OF BIOINDICATIVE PROPERTIES OF QUERCUS CASTANEIFOLIA С.А.MEY IN NATURALAND URBANIZED SITES IN AZERBAIJAN

2019 ◽  
pp. 71-79
Author(s):  
A. O. Mammadova ◽  
R. N. Mammadova
Keyword(s):  
Environmental Pollution ◽  
Fluctuating Asymmetry ◽  
Inductively Coupled Plasma ◽  
Morphological Characters ◽  
Developmental Stability ◽  
Soil Samples ◽  
Capital City ◽  
Chemical Components ◽  
Environmental Monitoring System ◽  
High Level

The paper presents a study of indicative and remediative properties of chestnut-leaved oak Quercuscastaneifolia C.A.Mey found in the Republic of Azerbaijan.The study aimed to assess the prospects of using this plant in the management of environmental quality in Azerbaijan. Four test sites, which differ in the degree of environmental pollution, were selected for the study. Two test sites are located in Baku, the capital city that has a rather high level of pollution. The other two test sites are located in the country.The bioindicative propertiesof chestnut-leaved oak were investigated by analyzing the developmental stability of leaves morphogenesis. To determine the developmental stability of leaves, the method of fluctuating asymmetry was used. Thebioaccumulativepropertiesofthe plantwere investigated by elementalanalysisofleavesandsoil. For this, the methods of sampling, sample preparation and sample were used according to GOST RF. The analysis of the main chemical components in the leaf and soil samples was carried out using an inductively coupled plasma mass spectrometerand an atomic absorption spectrometer. The analysis of micro-components in the leaf and soil samples was carried out using an X-ray fluorescence spectrometer. It was found that there is a strong correlation between the degree of environmental pollution and the level of developmental stability of morphological characters of Quercus castaneifolia C.A.Mey. Environmental pollution increases the fluctuating asymmetry of the leaves.The results also showed that Quercus castaneifolia C.A.Mey hasremediative properties. Therefore, chestnut-leaved oak can be a monitored species in the integrated environmental monitoring system in Azerbaijan.

Genetic-Variation Among Insular Populations of the Sleepy Lizard, Trachydosaurus-Rugosus Gray (Squamata, Scincidae)

1990 ◽  
Vol 38 (6) ◽  
pp. 603 ◽  
Author(s):  
S Sarre ◽  
TD Schwaner ◽  
A Georges
Keyword(s):  
Genetic Variation ◽  
Genetic Drift ◽  
Allelic Diversity ◽  
South Australia ◽  
Allozyme Electrophoresis ◽  
Specific Component ◽  
Genetic Characteristics ◽  
Island Populations ◽  
Evolutionary Forces ◽  
Insular Populations

Seven island populations of the sleepy lizard, Trachydosaurus rugosus, in South Australia were studied to establish the genetic effects of isolation. These effects were assessed by comparing genetic characteristics (using allozyme electrophoresis) of the island populations with those of three adjacent mainland populations. Heterozygosity levels did not vary significantly among the populations although the island populations exhibited reduced allelic diversity. Alleles that were rare on the mainland were not present in the island populations. Genetic divergence among the island populations was much greater than among populations on the mainland, reinforcing the notion that evolutionary forces, probably genetic drift, were greatest among the insular populations. This study demonstrates that the intra-specific component of variation can be significant, and that the importance of this component will increase with the fragmentation and isolation of populations. This finding serves to emphasis the importance of considering the population as the unit of conservation.

Morphological Characteristics of the Stroma in Malignat Epithelial Neoplasms with Short Review of Skin Squamous Cell Carcinoma

2014 ◽  
Vol 68 (1) ◽  
pp. 8-15
Author(s):  
Lena Kakasheva-Mazhenkovska ◽  
Vesna Janevska ◽  
Gordana Petrushevska ◽  
Liljana Spasevska ◽  
Neli Basheska
Keyword(s):  
Immune Cells ◽  
Complex Structure ◽  
Tumor Development ◽  
Morphological Characteristics ◽  
Basal Membrane ◽  
Short Review ◽  
Invasion And Metastasis ◽  
Genetic Changes ◽  
Cancer Associated Fibroblast ◽  
Skin Squamous Cell Carcinoma

Abstract The stroma of the neoplasm is a highly complex structure built by: specialized mesenchymal cells typical for each tissue surroundings, cancer associated fibroblast/myofibroblast, congenital or acquired immune cells, vascular network with endothelial cells and pericytes, mastocytes, macrophages, leukocytes and adipocytes, all together incorporated in the extracellular matrix. Each neoplasm produces its own unique microenvironment where the tumor grows and modifies. Although most of the cells of the host in the stroma have compulsory tumor suppressor ability, the stroma is changing during the malignant process and it even promotes growth, invasion and metastasis. Genetic changes that occur during the development of the cancer, which are guided by the malignant cells lead to changes in the stroma of the host that will overtake it and adjust it to their own needs. In the early stages of the tumor development and invasion, the basal membrane is degraded and the stroma becomes active and contains an increased number of fibroblasts, inflammatory infiltrate and newly composed capillaries which come into direct contact with the tumor cells. These changes lead to cancer invasion.

Inheritance of Some Morphological Characteristics of Parental Lines in Mustard-Rape Hybrid

2020 ◽  
pp. 23-30
Keyword(s):  
First Generation ◽  
Agronomic Traits ◽  
Morphological Characteristics ◽  
Morphological Characters ◽  
Hybrid Plant ◽  
Distant Hybridization ◽  
Degree Of Dominance ◽  
Whole Plant ◽  
Row Width ◽  
The Difference

Distant hybridization is known to play an important role in expanding the gene pool of any crop. It is believed that the combination of different genomes in one nucleus, as a rule, is accompanied by the phenomenon of “genomic shock”, resulting in a variety of genetic and epigenetic changes. This provides a wealth of material for the selection of genotypes adapted to different environmental conditions. Interspecific hybrids in different combinations were obtained in the genus Brassica, however, until now, interest in distant hybridization in this genus has not died out, since such important crops as rapeseed and mustard demand an improvement of many important agronomic traits. The aim of this work was to study the degree of manifestation of morphological characters of a leaf, flower, and plant as a whole in the hybrid obtained by crossing of brown mustard of the variety Slavyanka and a collection specimen of spring rape. Seeds were sown in the spring of 2019 in a field with 30 cm row width. During the flowering period a number of morphological characters of a flower, leaf, and the whole plant were analyzed. Each parameter was evaluated with 10 plants. The degree of dominance in first-generation hybrid was calculated by the formula of Beil, Atkins (1965). The dominance coefficients were not determined in the case when the difference between the parental samples was insignificant. Differences between parental samples were determined by Student t-test. The level of heterosis was calculated according to the formula of Rasul et al (2002). In a mustard-rapeseed hybrid, the size of the leaves of the lower row was inherited by the type of rapeseed, which had larger leaves than mustard. The height of the hybrid plant was inherited by the type of mustard (hp = 1.32, Ht = 4.89%), and intermediate inheritance was observed for the length of the internodes (hp = -0.48). The size of the flower petals and sepals was inherited by the type of rapeseed, and significant heterosis was observed for the length of the pistil (Ht = 33.57%). The data obtained are of interest for understanding the interaction of genes of different genomes in the genus Brassica.

scholarly journals Fluctuating Asymmetry and Developmental Instability, a Guide to Best Practice

Symmetry ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 9
Author(s):  
John H. Graham
Keyword(s):  
Measurement Error ◽  
Best Practices ◽  
Environmental Stress ◽  
Fluctuating Asymmetry ◽  
Best Practice ◽  
Developmental Instability ◽  
The Past ◽  
Size Scaling ◽  
Research Designs

Best practices in studies of developmental instability, as measured by fluctuating asymmetry, have developed over the past 60 years. Unfortunately, they are haphazardly applied in many of the papers submitted for review. Most often, research designs suffer from lack of randomization, inadequate replication, poor attention to size scaling, lack of attention to measurement error, and unrecognized mixtures of additive and multiplicative errors. Here, I summarize a set of best practices, especially in studies that examine the effects of environmental stress on fluctuating asymmetry.

scholarly journals Nature, Nurture, and Noise: Developmental Instability, Fluctuating Asymmetry, and the Causes of Phenotypic Variation

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1204
Author(s):  
John H. Graham
Keyword(s):  
Fluctuating Asymmetry ◽  
Phenotypic Variation ◽  
Deterministic Chaos ◽  
Monozygotic Twins ◽  
Developmental Instability ◽  
Nonlinear Feedback ◽  
Developmental Variation ◽  
Sewall Wright ◽  
Developmental Noise ◽  
And Behavior

Phenotypic variation arises from genetic and environmental variation, as well as random aspects of development. The genetic (nature) and environmental (nurture) components of this variation have been appreciated since at least 1900. The random developmental component (noise) has taken longer for quantitative geneticists to appreciate. Here, I sketch the historical development of the concepts of random developmental noise and developmental instability, and its quantification via fluctuating asymmetry. The unsung pioneers in this story are Hugo DeVries (fluctuating variation, 1909), C. H. Danforth (random variation between monozygotic twins, 1919), and Sewall Wright (random developmental variation in piebald guinea pigs, 1920). The first pioneering study of fluctuating asymmetry, by Sumner and Huestis in 1921, is seldom mentioned, possibly because it failed to connect the observed random asymmetry with random developmental variation. This early work was then synthesized by Boris Astaurov in 1930 and Wilhelm Ludwig in 1932, and then popularized by Drosophila geneticists beginning with Kenneth Mather in 1953. Population phenogeneticists are still trying to understand the origins and behavior of random developmental variation. Some of the developmental noise represents true stochastic behavior of molecules and cells, while some represents deterministic chaos, nonlinear feedback, and symmetry breaking.

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