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PubMed2002

Sex differences in jealousy: evolutionary mechanism or artifact of measurement?

Two studies are presented that challenge the evidentiary basis for the existence of evolved sex differences in jealousy. In opposition to the evolutionary view, Study I demonstrated that a sex difference in jealousy resulting from sexual versus emotional infidelity is observed only when judgments are recorded using a forced-choice response format. On all other measures, no sex differences were found; both men and women reported greater jealousy in response to sexual infidelity. A second study revealed that the sex difference on the forced-choice measure disappeared under conditions of cognitive constraint. These findings suggest that the sex difference used to support the evolutionary view of jealousy (e.g., D. M. Buss, R. Larsen, D. Westen, & J. Semmelroth, 1992; D. M. Buss et al., 1999) likely represents a measurement artifact resulting from a format-induced effortful decision strategy and not an automatic, sex-specific response shaped by evolution.

Adult↗
PubMedDate not supplied

[Formation of evolutionary approach as an explanatory principle for ecology].

Although the connection of ecology with evolutionary idea and specifically with Darwinism was proclaimed for a long time it seems that Herbert Spencer's approach with its emphasize on natural equilibrium was much more often used as its real theoretical base. Elements of Darwinian approach appeared only in 1920-30s in works of those few researchers who studying the distribution and population dynamics of different species tried to understand general mechanisms providing their continuing existence. Later, in the middle of 1950s the first attempts were undertaken to consider the population life history (primarily the age specific schedule of death and reproduction) as a result of natural selection aimed to maintain the necessary level of fitness. A special attention in these studies that burgeoned in 1980-90s was paid to looking for various trade-offs between particular parameters of life history, e.g., between the survival of juveniles and fecundity of adults. The problem of life history optimization became central for the whole branch of science named "evolutionary ecology". Though traditionally this branch is connected with Darwinism, it is rooted rather in Spencer's ideas on moving equilibrium and deals more with static than dynamic. Disproportionately less attention was paid to the evolution of communities since these formations could be hardly interpreted as units of Darwinian selection. Moreover, the ecologists dealing with biosphere as a unified biogeochemical system began insist on "nondarwinian" nature of its evolution. The author considers this opinion as not sufficiently grounded. Darwin's ideas about unavoidable exponential growth, intrinsic for any population, consequent deficiency of resources, and differential survival and reproduction of individuals are still useful while studying the evolution of living organisms (phylogenetics) or the development of biosphere as a global ecosystem.

Animals↗
PubMedDate not supplied

[Characters of amino acid substitution in LDH-A and LDH-B in the evolutionary line of vertebrates].

Structure of lactate dehydrogenase LDH-A (muscle) and LDH-B (heart) subunits is compared in the evolutionary line of vertebrates from Chondrosteous fishes to Mammals. It is revealed persistent differences between them in the amino acid set determining the physical and chemical characteristics of macromolecules. The polypeptide chain of LDH-A is shorter then that of LDH-B but it contains amino acids with higher molecular weight. In LDH-A polarized amino acids are less in number but charged amino acids are more numerous, positive charged amino acids prevail over negative charged ones. The features of polypeptide structure are discussed in connection with differences in the level of intraspecific variability of allozymes in the evolutionary line of vertebrates.

Amino Acid Substitution↗
PubMedDate not supplied

[Computer simulation of different types of evolutionary process].

The computer model of two alternative variants of biological evolution is proposed. The first variant supposes random while the second--directed change of individual features, thus corresponding to the Darwinian and non-Darwinian evolution. The evolution of fish communities in fresh waters serves as a particular example. The model is executed using object-oriented method of programming and mathematical apparatus of fuzzy logics. The investigation of the model showed that process of Darwinian evolution is connected with significantly greater species diversity and variability of evolutionary process trajectories than non-Darwinian one. On the other hand, non-Darwinian type of evolution provides fast achievement of high individual fitness, especially under conditions of constant environment. Non-Darwinian type evolution failed in big evolutionary alteration (for example, transition to predation); while the Darwinian evolution under the same conditions can produce such alterations though it took more time and many extinct species. Phylogenetic tree of Darwinian evolution is always more complex than of non-Darwinian one under the same conditions.

Animals↗
PubMed2004

Evolutionary recombination hotspot around GSDML-GSDM locus is closely linked to the oncogenomic recombination hotspot around the PPP1R1B-ERBB2-GRB7 amplicon.

PPP1R1B-STARD3-TCAP-PNMT-PERLD1-ERBB2-MGC14832-GRB7 locus at human chromosome 17q12 is frequently amplified in human gastric cancer and breast cancer. Here, we compared human GSDML-GSDM locus with rodent genomes by using bioinformatics. Rodent ortholog of human GSDML was not identified. Rat Gsdm gene was identified within rat genome clone CH230-28N16 (AC119462.4), and was mapped to rat chromosome 10q31. Rat Gsdm gene, consisting of 12 exons, encoded a 446-amino-acid protein, which showed 86.3% and 32.3% total-amino-acid identities with human GSDM and GSDML, respectively. Mouse Gsdm-like 1 (Gsdml1) and Gsdml2 genes were identified within mouse genome clone RP23-438D7 (AL591125.20). Gsdml1 and Gsdml2 genes were found to encode 456- and 443-amino-acid proteins, respectively. Mouse 2200001G21Rik cDNA (AK008613.1) was a partial cDNA derived from mouse Gsdml2 gene. Mouse Gsdml1 and Gsdml2 were also more homologous to human GSDM than to human GSDML. Mouse Gsdml1, Gsdml2 and Gsdm genes, existing in the tandem homologous gene cluster, was mapped to mouse chromosome 11D. Mouse Gsdml1-Gsdml2-Gsdm gene cluster was predicted to be generated due to triplication of mouse Gsdm gene, while GSDML gene was predicted to be generated due to duplication of GSDM gene. Evolutionary recombination hotspot around the GSDML-GSDM locus was closely linked to the oncogenomic recombination hotspot around the PPP1R1B-ERBB2-GRB7 amplicon. The evolutionary recombination hotspot and oncogenomic recombination hotspot might be clustered around the fragile sites within the human genome.

Amino Acid Sequence↗
PubMedDate not supplied

[Evolutionary development of the immunoglobulins super family].

The origin of the ability of immunoglobulins (Igs) and T-cell receptors (TCRs) to specifically recognize antigens is related to the evolutionary development of proteins of the immunoglobulin superfamily (IgSF). The IgSF proteins are characterized by specific domain organization of molecules and statistically significant homology with known Igs. Four types of Ig domains (V1, V2, C1, and C2), differing from one another both in variations in their spatial organization and in the number of amino acid residues, have been distinguished. Immunoglobulin superfamily comprises Igs; TCRs; class I and II major histocompatibility complex (MHC) molecules; one-domain proteins of thymocytes and T-cells (Thy-1); myelin protein P0; beta 2-microglobulin; two-domain proteins--sponge receptor tyrosine kinase (RTK), sponge adhesive protein (SAP), Drosophila tyrosine-kinase receptor (DTKR), cortical-thymocyte receptors of Xenopus (CTX), human (CTH), etc.; and a large group of adhesins, coreceptors, and Ig receptors with varying number of domains. Evolutionary development of IgSF began with the origination of chaperones, Thy-1, and P0 of prokaryotes and unicellular eukaryotes. Mutations, duplications, and translocations of genes controlling both V and C domains yielded proteins differing in the number and combination of these domains. All IgSF proteins are divided into two groups. The first group includes the proteins with nonrearranging V2 domains and homophilic mode of interaction; the second, the proteins with rearranging V1 domains and heterophilic mode of interaction (Igs, TCRs). The acquisition of the capability of heterophilic antigen-binding mode of interaction was apparently related to the introduction of recombination-activating retroviral genes (RAG1 and RAG2) into the genome of Gnathostomata ancestors.

Animals↗
PubMedDate not supplied

[The main directions of studies in evolutionary immunology].

The main directions in evolutionary immunology include: (1) study of phylogenetic relationships between nonspecific (hereditary) and specific (acquired, or adaptive) immunity; (2) study of the phenomena of graft rejection in a phylogenetic series; (3) study of occurrence and historical development of T- and B-systems of immunity; (4) study of phylogenesis of different cell types of the immunity system; and (5) study of historical development of the ability to specifically recognize foreign antigenic material. Because many problems of evolutionary immunology remain unsolved, studies in this field will be continued.

Allergy and Immunology↗
PubMed2005

Evolutionary history of contagious asexuality in Daphnia pulex.

Asexual taxa are short-lived, suggesting that transitions to asexuality represent evolutionary dead-ends. However, with high rates of clonal origin and coexistence of asexuals and sexuals via selective asymmetries, asexuality may persist in the long term as a result of a dynamic equilibrium between clonal origin and extinction. Few such systems have been studied in detail. Here, we investigate the evolutionary history of asexual lineages of Daphnia pulex, which are derived from sexual relatives via the inheritance of a dominant female-limited meiosis-suppressing locus and inhabit ponds throughout northeastern North America (NA). Our extensive sampling and subsequent phylogenetic analysis using mitochondrial sequence data reveals a young and genetically diverse asexual assemblage, reflecting high rates of clonal origin due to the contagious nature of asexuality. Yet, asexuality is restricted to two phylogroups (B and C) with historical and/or present associations with northeastern NA and is absent from a northwestern phylogroup (A), supporting a recent northeastern origin of asexuality in this species. Furthermore, macrogeographic patterns of genetic variability indicate that phylogroups B and C recolonized northeastern NA from opposite directions, yet their presently overlapping geographic distributions are similarly divided into an eastern asexual and a western sexual region. We attribute these patterns to a recent contagious spread of asexuality from a northeastern source. If environment-mediated selective asymmetries play no significant role in determining the outcome of competitive interactions between sexuals and asexuals, regions of contact may be setting the stage for continued asexual conquests.

Adaptation, Physiological↗
PubMed2005

Size as a line of least evolutionary resistance: diet and adaptive morphological radiation in New World monkeys.

New World monkeys (NWM) display substantial variation (two orders of magnitude) in body size. Despite this, variation in skull size and associated shape show a conserved allometric relationship, both within and between genera. Maximum likelihood estimates of quantitative ancestral states were used to compare the direction of morphological differentiation with the phenotypic (p(max)) and genetic (g(max)) lines of least evolutionary resistance (LLER). Diversification in NWM skulls occurred principally along the LLER defined by size variation. We also obtained measures of morphological amount and pace of change using our skull data together with published genetic distances to test whether the LLER influenced the amount and pace of diversification. Moreover, data on an ecological factor (diet) was obtained from the literature and used to test the association of this niche-related measure with the morphological diversification. Two strategies were used to test the association of LLER with the morphological and dietary amount and pace of change, one focusing on both contemporary genera and maximum likelihood reconstructed ancestors and the other using only the 16 contemporary genera in a phylogenetic comparative analysis. Our results suggest that the LLER influenced the path, amount, and pace of morphological change. Evolution also occurred away from the LLER in some taxa but this occurred at a slower pace and resulted in a relatively low amount of morphological change. We found that longer branch lengths (time) are associated with larger differences in p(max) orientation. However, on a macroevolutionary scale there is no such trend. Diet is consistently associated with both absolute size differences and morphological integration patterns, and we suggest that this ecological factor might be driving adaptive radiation in NWM. Invasion of diet-based adaptive zones involves changes in absolute size, due to metabolic and foraging constraints, resulting in simple allometric skull diversification along the LLER. While it is clear that evolutionary change occurred along the LLER, it is not clear whether this macroevolutionary pattern results from a conservation of within-population genetic covariance patterns or long-term adaptation along a size dimension or whether both constraints and selection were inextricably involved.

Adaptation, Physiological↗
PubMed2006

[Rational evolutionary design and modification of gene: a short-path of direct evolution].

Directed evolution is a powerful means in academic study and industrial application to modified and functionally improved proteins. There have been significant and impressive advances using the artificial method. Rational Evolutionary Design utilizes structural and sequence alignment information to create new genes and proteins. Rational Evolutionary Design has recently emerged as an attractive approach for studying function of proteins. The review mainly introduced four aspects: preferred codon usage, structural and sequence alignment, key domain analysis, site-directed recombination.

Directed Molecular Evolution↗
PubMedDate not supplied

[The construction of an evolutionary tree for signal receptor proteins].

A method is suggested for evolutionary tree building for proteins with low level of similarity. The degree of similarity is computed by conservative parts for a given family. The method allows to reveal the relationship of amino acid sequences even in cases when conventional techniques yield negative results. Evolutionary tree for signal receptor proteins is built. All the investigated proteins (except STE2) display non-accidental similarity.

Amino Acid Sequence↗
PubMed2006

Neutral theory, phylogenies, and the relationship between phenotypic change and evolutionary rates.

The neutral theory of molecular evolution predicts that rates of phenotypic change are largely independent from genotypic change. A recent study by Bromham et al. (2002) confirmed this expectation, finding no evidence for correlated phenotypic and molecular evolutionary rates in animals. We reevaluate this hypothesis, sampling at different taxonomic levels in plants and animals, using Bayesian inference to reconstruct phylogenetic trees and estimate rates of molecular evolution. We use independent contrasts in branch lengths to maximize the information extracted from each of the trees and nodal posterior probabilities to assess the influence of phylogenetic error. Our results indicate that in vascular plants between 2% and 11% of the variation in phenotypic rates of change can be explained by the rate of genotypic change. These results may be explained by the idea that processes that affect general evolutionary rates, such as body size, may also be expected to influence rates of morphological change.

Animals↗
PubMedDate not supplied

[Evolutionary psychiatry].

The author's perspective is that of a naturalist and ethologist. In this paper, he looks for evidences of phylogenetic components inherited from evolutionary adaptive behaviours in the etiology of psychopathological syndromes: bipolar depressions, seasonal affective disorders, obsessive-compulsive disorders, hysterical syndrome, impulsive behaviours, eating disorders, etc. Evolutionary psychiatry which sets present human pathological behaviour in the context of our species past evolution and of our ancestor's adaptations to their natural environment, leads the psychopathologist to revise certain of classic concepts in this field and resort to some of the concepts used by the ethologists, such as territory, hierarchy, allo-grooming and altruistic behaviour. It constitutes an invitation to reconsider the heredity of mental disorders in the light of phylogenetic consideration. As Freud and Lorenz have always recommended, one should not dissociate ontogeny from phylogeny in the study of human behaviour, whether normal or pathological.

Altruism↗
PubMed2006

Chromosomal evolution of elements B and C in the Sophophora subgenus of Drosophila: evolutionary rate and polymorphism.

The locations of 77 markers along the chromosomal elements B (41 markers) and C (36 markers) of Drosophila subobscura, D. pseudoobscura, and D. melanogaster were obtained by in situ hybridization on polytene chromosomes. In comparisons between D. subobscura and D. pseudoobscura, 10 conserved segments (accounting for 32% of the chromosomal length) were detected on element B and eight (17% of the chromosomal length) on element C. The fixation rate of paracentric inversions inferred by a maximum likelihood approach differs significantly between elements. Muller's element C (0.17 breakpoints/Mb/million years) is evolving two times faster than element B (0.08 breakpoints/Mb/million years). This difference in the evolutionary rate is paralleled by differences in the extent of chromosomal polymorphism in the corresponding lineages. Element C is highly polymorphic in D. subobscura, D. pseudoobscura, and in other obscura group species such as D. obscura and D. athabasca. In contrast, the level of polymorphism in element B is much lower in these species. The fixation rates of paracentric inversions estimated in the present study between species of the Sophophora subgenus are the highest estimates so far reported in the genus for the autosomes. At the subgenus level, there is also a parallelism between the high fixation rate and the classical observation that the species of the Sophophora subgenus tend to be more polymorphic than the species of the Drosophila subgenus. Therefore, the detected relationship between level of polymorphism and evolutionary rate might be a general characteristic of chromosomal evolution in the genus Drosophila.

Animals↗
PubMed2006

DNA fingerprinting elicited evolutionary trend of oral Candida tropicalis isolates from diverse geographic locales.

PURPOSE: To study molecular profiles of oral Candida tropicalis isolates from five different geographic locales to determine the molecular diversity, clonality and evolutionary trends of this opportunistic pathogen. METHODS: A total of 36 strains from five countries (China, Canada, Scotland, Japan and Tanzania) were genotyped by PCR fingerprinting with 11 separate primers. Of these, primers RSG9, RSG8, T3B and RSD12 generated complex fingerprinting patterns. RESULTS: Three significantly dissimilar profiles were derived from the primer T3B and particularly focused on tDNA suggested the prevalence of genetic subtypes within the species. Comparison of tDNA and rDNA (RSD12) fingerprints of C. tropicalis suggested that rDNA is much more heterogeneous than the relatively distinct tDNA. Further analysis of similarity coefficient (SAB) of gel profiles derived from computer-generated dendrograms indicated some degree of similarity in isolates from five-disparate geographic locales as well as the presence of unique isotypes in each region. CONCLUSIONS: This study demonstrates the evolutionary divergence of distinct genetic subgroups within Candida tropicalis .

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

[Evolutionary reorganizations of ontogenesis in related species of coenobial volvocine algae].

The evolutionary aspects of ontogenesis in green volvocine algae have been considered on the basis of the author's and published data, as well as the information on taxonomy, phylogeny, and ecology of this group. Analysis of the rate, diurnal rhythm, and light/dark control of cell divisions in various species, as well as experiments with the nucleic acid and protein synthesis inhibitors made it possible to elucidate cellular mechanisms underlying evolutionary rearrangements of asexual development in the genus Volvox.

Cell Division↗
PubMed1991

When is an evolutionary approach useful?

Evidence that human behavior is or has been adaptive comes from the likelihood that it would have been useful in our environment of evolutionary adaptedness, that it forms a coherent whole with other characteristics, and that variants contribute or would be likely to contribute to reproductive success. Belsky et al. use the second and third of these, though on the third their evidence is somewhat tenuous. However, their thesis does integrate diverse facts about parenting and development. In general an evolutionary approach is useful if it integrates diverse facts, if it aids clinical practice, and if it helps us toward a full understanding of human nature.

Animals↗
PubMedDate not supplied

Bipedal verticality, social behaviour, environmental adaptation and human evolutionary development.

The author has planned this research utilizing two models theoretically supported through biomechanical and mathematical laws, as they were formulated by means of data selected from paleoanthropological literature and his own clinic-instrumental case studies, on patients who were stimulated through manual pressure. The hypothesis was: is the paradoxical advantage reasonable for attaining and validating the mode of habitual, vertically aligned posture among evolutionary human-like beings through a vertical load upon their spine, as it is possible clinically in the course of rehabilitation? For assessing this argument two models, one biomechanical and the other mathematical were made up. They test the above mentioned load, as it reaches the clinically ascertained threshold value for triggering a firm gravitational alignment which is in agreement with bipedal gait. The suitability of the biomechanical model derives from reliability of the successively advancing levels of evolution (Anagenesis) from monkeys, through apes, to humans. This model was selected among the postural behaviours that were roughly antecedent to Hominidae bipedalism. So it was possible to abstract an Ape-like anteriorly sloping being, who under the above described stimulation through a suitable load on his-her neck-trapezius muscle angle is submitted to the flow of vertical forces as they show a tendency to aligning vertically the gravitational centers of head, thorax, abdominal masses. So, the biomechanics of the Ape-like being becomes the biomechanics of a mere Man-like mode of functional firm vertical alignment. The suitability of the mathematical model is in agreement with the reliability of the body of a Man-like being which is likened to a cylinder progressing chiefly through rotational and translational torques. The detailed sequence of the mechanical laws of stationary and dynamic equilibrium of rigid bodies and of elasto-mechanical law leads us to an understanding of abstracted sites as they in the course of human evolution were centering the characteristic osseous changes of humans which became the adaptative changes such as they are shown in fossil remains. The vertical alignment should have been validating through the advantageous carrying of loads of suitable weight. This, in turn, should have contributed to evolution of functional erect posture and gait through minimization of the centralised force-tension by means of a stepwise widening about some muscular attachments. So the nuchal part of the occipital bone widened while the increased capacity of enlarging pelvis of the evolutionary woman became adapted to accepting a larger fetal skull.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗