scispace - formally typeset
Search or ask a question
Topic

Fluctuating asymmetry

About: Fluctuating asymmetry is a research topic. Over the lifetime, 1314 publications have been published within this topic receiving 50311 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: Why, then, all the recent (and not so recent) interest in such minor, nondirectional deviations from bilateral symmetry [fluctuating asymmetry (FA)?
Abstract: With these words Darwin opened a brief paragraph citing observations antithetical to his supposition: anecdotal reports of the inheritance of characters missing from one side of the body. His initial hunch, however, has stood the test of time: Genetic studies have confirmed that where only small, random deviations from bilateral symmetry exist, the deviations in a particular direction have little or no measurable heritability (17, 47, 51, 65a, 73a, 74, 91). The genetic basis of bilateral symmetry thus appears to differ fundamentally from that of virtually all other morphological features. Why, then, all the recent (and not so recent) interest in such minor, nondirectional deviations from bilateral symmetry [fluctuating asymmetry (FA); 60 cited in 99]? Four reasons. First, FA relates in a curious way to what is perhaps the major unsolved general problem in modem biology: the orderly expression of genotypes as complex, three-dimensional phenotypes. As was emphasized in a flurry of activity in the mid to late 1950s, and many times since, FA provides an appealing measure of 'developmental noise,' or minor environmentally induced departures from some ideal developmental program (101). Its appeal derives from an a priori knowledge of the ideal: perfect bilateral symmetry. For unilateral characters, the ideal is rarely known (but see 1, 2, and 59 for one possible approach). A second reason for interest in

2,025 citations

Journal ArticleDOI
TL;DR: No new evidence is given as to buffering against environmental stresses of a larger scale, such as temperature or the presence of parasites, but a mean positive correlation between the fluctuating asymmetries of a number of un-
Abstract: Fluctuating asymmetry, discussed below, is commonly used to estimate the effects of minor developmental accidents. These accidents differ between individuals, and there are also individual differences in resistance to these accidents. The ability to resist such developmental accidents will here be referred to as buffering against them. Because of the interrelations of morphogenetic systems, it is possible that an organism well buffered in one character is also well buffered in others, i.e., for this reason the microenvironmental perturbations on different systems in an individual may result in a tendency for the fluctuating asymmetry of different characters in that individual to be higher or lower than usual. Such a correlation in buffering capacities could also-be produced by differences in genotypes and environments acting separately'on different morphogenetic systems, but this is another matter. This investigation concerns the fluctuating asymmetry of different characters. No new evidence is given as to buffering against environmental stresses of a larger scale, such as temperature or the presence of parasites. A mean positive correlation between the fluctuating asymmetries of a number of un-

1,560 citations

Journal ArticleDOI
TL;DR: There is no evidence that special developmental processes control fluctuating asymmetry, and some of the morphometric patterns are related to processes known to be involved in the development of fly wings.
Abstract: Although fluctuating asymmetry has become popular as a measure of developmental instability, few studies have examined its developmental basis. We propose an approach to investigate the role of development for morphological asymmetry by means of morphometric methods. Our approach combines geometric morphometrics with the two-way ANOVA customary for conventional analyses of fluctuating asymmetry and can discover localized features of shape variation by examining the patterns of covariance among landmarks. This approach extends the notion of form used in studies of fluctuating asymmetry from collections of distances between morphological landmarks to an explicitly geometric concept of shape characterized by the configuration of landmarks. We demonstrate this approach with a study of asymmetry in the wings of tsetse flies (Glossina palpalis gambiensis). The analysis revealed significant fluctuating and directional asymmetry for shape as well as ample shape variation among individuals and between the offspring of young and old females. The morphological landmarks differed markedly in their degree of variability but multivariate patterns of landmark covariation identified by principal component analysis were generally similar between fluctuating asymmetry (within-individual variability) and variation among individuals. Therefore there is no evidence that special developmental processes control fluctuating asymmetry. We relate some of the morphometric patterns to processes known to be involved in the development of fly wings.

816 citations

Journal ArticleDOI
24 Jun 1999-Nature
TL;DR: It is shown that female preference for secondary sexual traits in male face shapes varies with the probability of conception across the menstrual cycle, similar to that of men with low fluctuating asymmetry.
Abstract: Women prefer slightly feminized male facial shapes1. Such faces (Fig. 1a) are given positive personality attributions1 that might correlate with actual behaviour2. In contrast, masculine features seem to signal immunological competence3. Heritable benefits can be realized only if conception follows copulation, so women might be more attentive to phenotypic markers indicating immunological competence during the follicular phase of the menstrual cycle when conception is most likely4,5. Consistent with this hypothesis is the observation that women's preference for the odour of men with low fluctuating asymmetry (a correlate of testosterone-facilitated trait size and developmental stability) increases with the probability of conception across the menstrual cycle5.Symmetrical men report more extra-pair copulation partners6, and extra-pair copulation rates peak in midcycle7. Here we show that female preference for secondary sexual traits in male face shapes varies with the probability of conception across the menstrual cycle.

807 citations

Journal ArticleDOI
TL;DR: Fuctuating asymmetry is a useful trait for monitoring stress in the laboratory and in natural environments and can be a useful parameter for evaluating the resilience of animals to natural disasters.
Abstract: (1) Fluctuating asymmetry (FA) is a useful trait for monitoring stress in the laboratory and in natural environments. (2) Both genomic and environmental changes can increase FA which represents a deterioration in developmental homeostasis apparent in adult morphology. Genetic perturbations include intense directional selection and certain specific genes. Environmental perturbations include temperature extremes in particular, protein deprivation, audiogenic stress, and exposure to pollutants. (3) There is a negative association between FA and heterozygosity in a range of taxa especially fish, a result consistent with FA being a measure of fitness. (4) Scattered reports on non-experimental populations are consistent with experiments under controlled laboratory conditions. FA tends to increase as habitats become ecologically marginal; this includes exposure to environmental toxicants. (5) In our own species, FA of an increasing range of traits has been related to both environmental and genomic stress. (6) Domestication increases FA of the strength of homologous long bones of vertebrate species due to a relaxation of natural selection. (7) FA levels are paralleled by the incidence of skeletal abnormalities in stressful environments. (8) Increased FA is a reflection of poorer developmental homeostasis at the molecular, chromosomal and epigenetic levels.

770 citations


Network Information
Related Topics (5)
Sexual selection
9.9K papers, 588.7K citations
89% related
Biological dispersal
30K papers, 1.2M citations
83% related
Animal ecology
30.8K papers, 1M citations
83% related
Foraging
19.8K papers, 708.7K citations
81% related
Population genetics
11.7K papers, 650.4K citations
81% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202345
202266
202136
202038
201933
201842