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1

Developmental stability of the mink Mustela vison under the impact of PCB

100%
Borisov V. I., Baranov A. S., Valetsky A. V., Zakharov V. M.
Acta Theriologica. Supplement
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1997
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nr 04
Females of the American mink Mustela vison Schreber, 1777 were fed on various fractions of comercial PCB. Developmental stability of their progeny was studied. Developmental stability was measured by the value of fluctuating asymmetry, and the frequency of phenodeviants of osteological and dermatoglyphic characters. All these measures proved to be significantly higher in the experimental intoxicated groups than in the control group, thus indicating deterioration of developmental stability from PCB.
2

Phenotypic diversity and population dynamics: another look (with particular reference to the common shrew Sorex araneus)

86%
Zakharov V. M., Pankakoski E., Sheftel B. I.
Acta Theriologica. Supplement
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1997
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nr 04
We studied temporal changes in the level of phenotypic diversity, measured by the total phenotypic variance for several characters of skull morphology, in two populations of the common shrew Sore:e araneus Linnaeus, 1758. We compared a population from central Siberia having a high-amplitude four-year cycle with a population from southern Finland having noncyclic dynamics. The level of total phenotypic diversity varied significantly among years in both populations, but was correlated neither with density nor with breeding success in either of them. We did, however, find differences between the two populations. When we compared changes in the level of phenotypic diversity with changes in the level of developmental stability, as measured by chance developmental variance (fluctuating asymmetry), the cyclic Siberian population exhibited increased developmental variability in the peak year, which was associated with relatively small proportion of other sources of variation (and genetic variation in particular). In other years, the role of chance variation was less and the proportion of other sources of variance was higher. On the other hand, in the noncyclic Finnish population, oscillations in the level of phenotypic diversity were mainly caused by changes in developmental stability. These results illustrate that not only dynamics of genotype variety, but also the alterations in the level of developmental stability can be of great importance for changes in phenotypic diversity.
3

Inbreeding and outbreeding impact on developmental stability of laboratory rat Rattus norvegicus

86%
Borisov V. I., Valetsky A. V., Dmitrieva I. L., Krushinskaya N. L., Zakharov V. M.
Acta Theriologica. Supplement
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1997
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nr 04
Developmental stability analysis was conducted for three strains of laboratory rat Rattus norvegicus Berkenhout, 1769 and their hybrids. Developmental stability was estimated by fluctuating asymmetry of 20 characters of skull morphology. A decrease was revealed in fluctuating asymmetry for the inbred strains and for the hybrids of genetically different strains. There were not any differences in fluctuating asymmetry between the homo- and heterozygotes for the separate locus. This support the hypothesis of the dependence of developmental stability on general genetic coadaptation.
4

Enzyme heterozygosity and developmental stability

86%
Mitton J. B.
Acta Theriologica. Supplement
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1995
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nr 03
Regular development of morphology is challenged by any environmental influence that draines energy from developing individuals. For half a century biologists have recognized that developmental stability, measured as the capability to regulate development of normal morphological structures, is influenced by genetic variation. This review considers the influence of enzyme polymorphism upon developmental stability. Empirical studies in a wide variety of animals have reported morphological variability and bilateral asymmetry to decrase with the heterozygosity of enzyme polymorphisms. A controversy focuses on the question of whether enzyme polymorphisms directly influence energy budgets and metabolism, or whether the enzymes are neutral markers that either reveal variation in levels of inbreeding or are in linkage disequilibrium with genes directly influencing development. Another controversy focuses on whether the relationships between enzyme heterozygosity and development stability, most commonly reported in poikilotherms, will also be found in homeotherms. These controversies are addressed by considering recent empirical studies of enzyme polymorphism and developmental stability. Kinetic and physiological studies have now established that enzyme polymorphisms can have a major impact upon flux through metabolic pathways and physiological variation. Enzyme heterozygosity is associated with resistance to parasites, which may decrease developmental stability. Enzyme heterozygosity is also related to secondary sexual characters, such as the size and symmetry of horns in white-tailed deer and the size of horns in bighorn sheep. Because symmetry is so important in sexual selection, the development of secondary sexual characters may yield important insights to the relationship between heterozygosity and developmental stability. Many empirical observations are consistent with hypothesis that enzymes have a direct influence on developmental stability. It is not likely that the relationship between heterozygosity and developmental stability will differ substantially between poikilotherms and homeotherms.
5

Social stress impact on developmental stability of laboratory rat Rattus norvegicus

72%
Valetsky A. V., Dmitrieva I. L., Krushinskaya N. L., Zakharov V. M.
Acta Theriologica. Supplement
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1997
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nr 04
Developmental stability of the progeny of pregnant female rats Rattus norvegicus Berkenhout, 1769 kept under different conditions was studied. In two experimental groups, females were exposed to social stress by keeping them in crowded cages at different stages of pregnancy, from the 1st to the 15th and from the 16th to the 21th days, respectively. In the control group, pregnant females were kept under normal conditions. Fluctuating asymmetry of 20 skull characters (number of foramina for small blood vessels and nerves) was used as a measure of developmental stability. Variance of the difference in foramen number between the left and right sides of the skull (1-r) as well as mean number of asymmetrical traits per individual revealed an increase of fluctuating asymmetry in both experimental groups compared with the control group. These results imply the deterioration of developmental stability under impact of social stress.
6

Developmental stability and population dynamics of shrews Sorex in Central Siberia

72%
Zakharov V. M., Demin D. V., Baranov A. S., Borisov V. I., Valetsky A. V., Sheftel B. I.
Acta Theriologica. Supplement
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1997
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nr 04
We examined temporal variation in developmental stability measured by fluctuating asymmetry of 10 skull characters in sympatric populations of three shrew species: Sorex araneus Linnaeus, 1758, S. caecutiens Laxmann, 1788 and S. tundrensis Merriam, 1900 from one locality in central Siberia with a high four-year-cycle of small mammals. Simultaneous significant changes in developmental stability have been revealed during a population cycle 1986-1989 for all three, most abundant shrew species in the locality. The highest asymmetry for all these species occurred in the year of maximal density. Similar high asymmetry was found for the separate samples of two other species: S. roboratus Hollister, 1913 and S. isodon Turov, 1924, collected in a peak year 1989 only. The maximal density in 1989 corresponded to the lowest level of breeding success and developmental stability and, vice versa, minimal density in 1986 was accompanied by the highest level of breeding success and developmental stability. These data suggest that overpopulation caused by high density of various small mammals adversely affects an organism's condition. Thus, developmental stability may be used to monitor possible changes in a population even in cases where direct estimation of fitness is difficult.
7

Developmental stability in hybrids of European bison Bison bonasus and domestic cattle

72%
Baranov A. S., Zakharov V. M.
Acta Theriologica. Supplement
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1997
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nr 04
We examined fluctuating asymmetry of 25 characters of skull morphology (foramina, apertures through the bone for nerves and small blood vessels) to estimate the developmental stability of European bison Bison bonasus (Linnaeus, 1758) (n = 34), cattle (n = 13) and their hybrids (54 hybrids of different generations). Mean number of asymmetrical characters per individual was used as a measure of fluctuating asymmetry. European bison were characterized by a lower developmental stability, compared with cattle. The developmental stability of hybrids was similar to that of cattle and higher than that of European bison. These findings suggest that the genomes of parental forms are similar and that there is no indication of the disruption of genetic coadaptation in their hybrids.
8

Inbreeding and developmental stability in a laboratory strain of the bank vole Clethrionomys glareolus

72%
Zakharov V. M., Sikorski M. D.
Acta Theriologica. Supplement
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1997
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nr 04
Developmental stability and phenotypic diversity of the bank vole Clethrionomys glareolus Schreber, 1780 were tested in a group of founders collected from natural population in Białowieża National Park (Poland) and in a sample taken from the 20th generation of a laboratory mass-cross strain derived from these founders. Fluctuating asymmetry of 28 skull characters such as the number of foramina were used as a measure of developmental stability. Variance of the foramina on the left and right sides of the skull for the same characters was used as a measure of phenotypic diversity. The data obtained indicate a developmental stability decrease and phenotypic diversity increase as a result of inbreeding during 20 generations in the laboratory.
9

Dynamics of developmental stability of seals and pollution in the Baltic Sea

72%
Zakharov V. M., Valetsky A. V., Yablokov A. V.
Acta Theriologica. Supplement
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1997
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nr 04
Fluctuating asymmetry of skull characters, as a measure of developmental stability, wás studied in two seal species: grey seal Halichoerus gry pus (Fabricius, 1791), and ringed seal Pusa hispida Schreber, 1775 from the Baltic Sea. Seals were collected in three different periods of water pollution of the Baltic Sea. We revealed the same temporal dynamics of fluctuating asymmetry level for both species: it proved to be low in "pre-pollution period" (years 1877-1936), high for the "high-pollution period" (1964-1975), and was again low for the "low-pollution period" (1986-1990). These data suggest that changes in the condition of the seal populations in the Baltic Sea revealed by changes in developmental stability are correlated with the dynamics of the pollution level.
10

Developmental stability of skull morphology in European bison Bison bonasus

72%
Baranov A. S., Pucek Z., Kiseleva E. G., Zakharov V. M.
Acta Theriologica. Supplement
|
1997
|
nr 04
We compared developmental stability and total phenotypic diversity of 25 skull characters in three populations of European bison Bison bonasus (Linnaeus, 1758). Developmental stability was measured by fluctuating asymmetry, which was estimated by the variance of the left-right (1—r) and scaled (l-r)/(l+r) differences between the left (1) and right (r) sides of the skull. Mean number of asymmetrical characters per individual was used as an integrated index of developmental stability. Total phenotypic variability was examined by variance of (1+r) for the same characters. Greater developmental instability and total phenotypic diversity were found in bison from Pszczyna Reserve and Białowieża Primeval Forest, as compared with those from Okskii Reserve. This indicates the gradiial deterioration of developmental stability in the following sequence of the studied populations: Okskii' Reserve, Białowieża Primeval Forest, Pszczyna Reserve. In the Białowieża population, deterioration of developmental stability could be detected, even though commonly used fitness measures showed no response. In the Pszczyna population, more serious developmental stability disturbance was accompanied by decreasead viability, an expression of inbreeding depression. Two samples taken from the Białowieża population at different times showed similar levels of developmental stability, which indicates the reliability of fluctuating asymmetry. These results suggest developmental stability to be an essential characteristic for monitoring populations and especially for revealing the initial response to stress.
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