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PubMed2002

Evolutionary experiments on mate recognition in the Drosophila serrata species complex.

It is becoming increasingly apparent that at least some aspects of the evolution of mate recognition may be amenable to manipulation in evolutionary experiments. Quantitative genetic analyses that focus on the genetic consequences of evolutionary processes that result in mate recognition evolution may eventually provide an understanding of the genetic basis of the process of speciation. We review a series of experiments that have attempted to determine the genetic basis of the response to natural and sexual selection on mate recognition in the Drosophila serrata species complex. The genetic basis of mate recognition has been investigated at three levels: (1) between the species of D. serrata and D. birchii using interspecific hybrids, (2) between populations of D. serrata that are sympatric and allopatric with respect to D. birchii, and (3) within populations of D. serrata. These experiments suggest that it may be possible to use evolutionary experiments to observe important events such as the reinforcement of mate recognition, or the generation of the genetic associations that are central to many sexual selection models.

Animals↗
PubMed1976

[Severbal new problems in evolutionary histology].

The classical evolutionary histology as a most important section of theoretical morphology created by workd of A.A. Zavarzin, N.G. Khlopin and A.V. Rumiantsev needs a revision on the basis of achievements of modern morphology, first of all the experimental morphology which have accumulated a vast factual material on a repeated (regenerative, transplantational, inflammatory) morphogenesis, brought about on the basis of the constructive (plastic) activity of tissues which escaped the researchers' attention in the classical period of development of evolutionary histology. A demand to create a new system of the tissue, based on characteristics of their plastic (constructive) activity became urgent. The proposed attempt of the evolutionary classification of tissues comes from the experience of researches of the constructive (plastic) activity of tissues, with the Darwin--Severtsov rule of the dependence of every individual and phylogenetic change of the organization of its pre-existing state taken into consideration.

Animals↗
PubMedDate not supplied

[Evolutionary saturation of species pool in present high mountain plant communities of Western Caucasus].

The relative level of evolutionary saturation/nonsaturation of high mountain plant communities in Western Caucasus was defined by analysis of correlation between their local richness (LR) and size of species pool (SP). It is expected that if compared biotas are differently distant from the point of equilibrium one should look forward to a significant variation in correlation between LR and SP determined with the greater sensitivity of LR in comparison with SP in respect of abiotic factors. The lower is correlation LR/SP the greater is level of evolutionary nonsaturation in analysed communities. The results of analysis confirm the assumptions on 1. incompleteness of flora development in the high mountain zone in Western Caucasus, 2. different ages of alpine and subalpine communities, 3. different time necessary to attain the equilibrium with species pools of communities formed under extreme and more favourable conditions, 4. dependence of temps of flora development on the isolation of mountain ridges and massifs. The species pools of the most extreme alpine ecotope communities characterized by low environment capacity (plant groups of moving taluses, low-species communities of alpine tapises, meadows and grounds) as well as the most of subalpine communities are evolutionary saturated or close to this condition. Development of species pools of alpine multi-species low-grass meadows as well as some of subalpine middle-grass meadows evidently is not completed yet. They can be considered to be the most probable places of the new species appearance by speciation or immigration from another Caucasus regions.

Biological Evolution↗
PubMedDate not supplied

[Schizophrenia in the light of the evolutionary theories].

The aim of the article was to review the hypotheses of schizophrenia in the light of the evolutionary theory. The authors distinguished adaptationist and non-adaptationist hypotheses concerning the evolutionary underpinnings of schizophrenia. The adaptationist hypotheses are firmly based on notions of adaptation, natural selection and proximate and ultimate causes. The standard hypotheses of this sort proposed by Steven and Price as well as by Pollimeni and Reiss were discussed. Also, the other similar conceptions originated from McGuire and Troisi and proposed by David Horrobin were presented of which the latter is especially promising and worth further investigating. The non-adaptationistic authors criticised many assumptions of the adapationist program i.e. too broad use of term "adaptation" in the area of human behaviour or the very idea of proximate and ultimate causes. Unlike the adaptionists, they focus their attention on other aspects of the evolutionary processes i.e. the role of the mutation and also they are searching in a much intensive way than their opponents for verification of the hypotheses based on the empirical evidence. The theories developed by Crow and by Yeo were listed among the non-adaptationistic ones and presented.

Adaptation, Physiological↗
PubMed2004

[Evolutionary predecessors of oncogenesis and old age involution].

A hypothesis is stated explaining emergence of mechanisms of oncogenesis and old age involution. According to the hypothesis the destructive and proliverative phenomena, observed in the course of these pathological processes, emerged on the basis of the destructive and proliverative phenomena, assotiated with asexual reproduction in the Precambrian Metazoa. The evolutionary predecessor of the oncogenesis was semelparous asexual reproduction, and the evolutionary predecessor of the old age involution was desintegration of tissues associated with iteroparous asexual reproduction. The oncogenesis and old age involution in different lines of the Metazoa originated independently. Processes of the normal ontogenesis in the contempory primitive Invertebrates are pointed out. These are the evolutionary predecessors of regression of tumors and haemoblastosis. The importance of regressive development is discussed.

Aging↗
PubMed2006

Evolutionary responses of native plants to novel community members.

Both ecological and evolutionary processes can influence community assembly and stability, and native community members may respond both ecologically and evolutionarily as additional species enter established communities. Biological invasions provide a unique opportunity to examine these responses of native community members to novel species additions. Here, I use reciprocal transplant experiments among naturally invaded and uninvaded environments, along with experimental removals of exotic species, to determine whether exotic plant competitors and exotic insect herbivores evoke evolutionary changes in native plants. Specifically, I address whether the common native plant species Lotus wrangelianus has responded evolutionarily to a series of biological invasions by adapting to the presence of the exotic plant Medicago polymorpha and the exotic insect herbivore Hypera brunneipennis. Despite differences in selection regimes between invaded and uninvaded environments and the presence of genetic variation for traits relevant to the novel competitive and plant-herbivore interactions, these experiments failed to reveal evidence that Lotus has responded evolutionarily to the double invasion of Medicago followed by H. brunneipennis. However, when herbivory from H. brunneipennis was experimentally reduced, Lotus plants from source populations invaded by Medicago outperformed plants from uninvaded source populations when transplanted into heavily invaded destination environments. Therefore, Lotus showed evidence of adaptation to Medicago invasion but not to the newer invasion of an exotic shared herbivore. The presence of this exotic insect herbivore alters the outcome of evolutionary responses in this system and counteracts adaptation by the native Lotus to invasion by the exotic plant Medicago. This result has broad implications for the conservation of native communities. While native species may be able to adapt to the presence of one or a few exotics, a multitude of invasions may limit the ability of natives to respond evolutionarily to the novel and frequently changing selection pressures that arise with subsequent invasions.

Adaptation, Physiological↗
PubMed2006

Evolutionary significance of geographic variation in a plumage-based foraging adaptation: an experimental test in the slate-throated redstart (Myioborus miniatus).

Geographic variation in the plumage pattern of birds is widespread but poorly understood, and in very few cases has its evolutionary significance been investigated experimentally. Neotropical warblers of the genus Myioborus use their contrasting black-and-white plumage to flush insect prey during animated foraging displays. Although previous experimental work has demonstrated that white plumage patches are critical to flush-pursuit foraging success, the amount of white in the plumage shows considerable interspecific and intraspecific geographic variation. We investigated the evolutionary significance of this geographic variation by experimentally decreasing or increasing the amount of white in the tail of slate-throated redstarts (Myioborus miniatus comptus) from Monteverde, Costa Rica, to mimic the natural extremes of tail pattern variation in this species. In addition to measuring the effects of plumage manipulation on foraging performance, we performed field experiments measuring the escape response of a common insect prey species (an asilid fly) using model redstarts representing four different Myioborus plumage patterns. Our experiments were designed to test four hypotheses that could explain geographic variation in plumage pattern. Compared to controls, experimental birds with reduced-white tails that mimic the plumage pattern of M. miniatus hellmayri of Guatemala showed significant reductions in flush-pursuit foraging performance. In contrast, the addition of white to the tail to mimic the plumage pattern of M. miniatus verticalis of Bolivia had no significant effect on foraging performance of Costa Rican redstarts. In field experiments with asilid flies, model redstarts simulating the plumage of M. miniatus comptus of Costa Rica and M. miniatus verticalis of Bolivia elicited greater responses than did models of other Myioborus taxa with either less or more white in the plumage. The results of our experiments with both birds and insects allow us to reject two hypotheses for geographic variation in plumage pattern: (1) that geographic variation is a nonadaptive result of genetic drift, and (2) that selection for enhanced flush-pursuit foraging performance generally favors increased white in the plumage, but evolutionary trade-offs constrain the evolution of extensive patches of white in some geographic regions. Instead, our results suggest that geographic variation in the plumage pattern of Myioborus redstarts reflects adaptation to regional habitat characteristics that enhances flush-pursuit foraging performance.

Animals↗
PubMedDate not supplied

[Evolutionary aspects of affective disorders, critical review and proposal of a new model].

Evolutionary psychopathology incorporates psychiatry into biology via theory of evolution, generating new etiological hypothesis for mental disorders. For evolutionary psychopathology emotions are a response system or a genetically programmed, specialized state of functioning, formed by natural selection, that allows us to adapt to the environment, increasing the ability to cope with threats and opportunities. Emotions exert their function by coordinated physiological, psychological and behavioral changes. Many functions have been suggested for low mood or depression, including communicating a need for help, signaling yielding in a hierarchy conflict, fostering disengagement for commitments to unreachable goals, regulating patterns of investment, parallelism with despair phase of separation from mother situation in monkeys, hibernation, etc. Despite other evolutionary models, our model not only tries to explain depression but mania, hypomania and other affective disorders as well. For us, most affective disorders are pathological states (and not adaptive ones), due to dysfunction of an innate precipitating mechanism (IPM). IPM function is to regulate energy and activity levels according to intensity and duration of light (namely IPM-A). This IPM-A is responsible for vegetative, endocrine and behavioral responses that are present in humans and more ancient phylogenetic animals. More recently in the phylogeny, other mechanisms (IPM-AA) have coupled to this IPM-A. In the human being, the precipitating factors of IPM-AA are predominately social. IPM-AA add new responses (such as mood) to the older responses of IPM-A.

Biological Evolution↗
PubMed2005

Chance, explanation, and causation in evolutionary theory.

Chance comes into plays at many levels of the explanation of the evolutionary process; but the unity of sense of this category is problematic. The purpose of this talk is to clarify the meaning of chance at various levels in evolutionary theory: mutations, genetic drift, genetic revolutions, ecosystems, macroevolution. Three main concepts of chance are found at these various levels: luck (popular concept), randomness (probabilistic concept), and contingency relative to a given theoretical system (epistemological concept). After identifying which concept(s) of chance fit(s) with these levels, the question is raised whether these concepts can be reduced to a smaller number, and whether chance in evolutionary theory has a subjective or an objective sense.

Adaptation, Biological↗
PubMedDate not supplied

[Evolutionary concepts of affective disorders].

Mood may be considered the module of the human mind, which has evolved to tune the activity ofthe organism to the specific environmental conditions in a better way. In some cases depression may be adaptive, for example in aborting the activity associated with too many obstacles. At the same time hypomania may be related to the capability of mobilising the organism to gain many resources in a short period of time. Severe mood disorders may be related to the genetic variants, eg. of the serotonin transporter or brain-derived neurotrophic factor, which in several situations may give some evolutionary advantage. Affective temperaments, observed in the relatives of patients with affective disorders may be associated with some benefits in the social life. The relationship between early adversities and adult depression may be related to the phenomenon of the stress axis programming, which has deep evolutionary roots. Some infectious factors may cause behaviours similar to the affective symptoms, which may increase their reproductive success. The evolutionary perspective, which is complementary to the current etiopathogenic theories may help in understanding, why genes and traits which

Affective Symptoms↗
PubMedDate not supplied

HIV evolutionary dynamics within and among hosts.

The HIV evolutionary processes continuously unfold, leaving a measurable footprint in viral gene sequences. A variety of statistical models and inference techniques have been developed to reconstruct the HIV evolutionary history and to investigate the population genetic processes that shape viral diversity. Remarkably different population genetic forces are at work within and among hosts. Population-level HIV phylogenies are mainly shaped by selectively neutral epidemiologic processes, implying that genealogy-based population genetic inference can be useful to study the HIV epidemic history. Such evolutionary analyses have shed light on the origins of HIV, and on the epidemic spread of viral variants in different geographic locations and in different populations. The HIV genealogies reconstructed from within-host sequences indicate the action of selection pressure. In addition, recombination has a significant impact on HIV genetic diversity. Accurately quantifying both the adaptation rate and the population recombination rate of HIV will contribute to a better understanding of immune escape and drug resistance. Characterizing the impact of HIV transmission on viral genetic diversity will be a key factor in reconciling the different population genetic processes within and among hosts.

Adaptation, Biological↗
PubMed1990

The Spalacidae: evolutionary history, speciation and population biology.

The evolutionary history of Spalacidae is reviewed taxonomically, paleontologically and neontologically. We focused selectively on taxonomy, biogeography, paleontology and evolutionary origins, chromosomal evolution, population biology and the species concept in Spalacidae. We concluded that the taxonomy of Spalacidae needs a modern revision based on chromosome and molecular-genetic data, beside that of morphology, physiology and behavior. The subterranean Spalacidae originated probably from a muroid-cricetoid stock in Asia Minor or vicinity, in Upper Oligocene times and adaptively radiated underground in the Balkans, steppic Russia and Middle East, extending into North Africa. The major important evolutionary feature in peripatric or allopatric speciation and adaptive radiation was karyotypic evolution, primarily through Robertsonian changes. More than 30 karyotypes (2n = 38-62; NF = 72-124) earlier represented by 8 classical species, occur primarily allopatrically or parapatrically, with only marginal sympatry, across the Eastern Mediterranean range of the family. Most karyotypes represent biospecies adapted at multiple organizational levels to their different ecologies. A short overview is presented on population biology and life history parameters of the Spalacidae which result in K-selected, "equilibrium species". Speciation in action and adaptive radiation embracing molecular and organismal adptations to the subterranean unique ecotope and to four different climatic regimes, have been multidisciplinarily studied in the Israeli Spalax ehrenbergi superspecies.

Animals↗
PubMed1987

[Inheritance and expression of dominant genes with variable penetration: the evolutionary aspect].

According to up-to-date literature, one of the approaches to elucidating the essence of evolutionary events consists in admitting the importance of events which change genome activity. A crucial way of reorganization of gene activity is the inhetrited activation or inactivation of the genes. "Dormant" gene hypothesis and related data are reviewed in this connection. Most attention is concentrated on the study of inheritance and penetrance of fused gene in mice. By means of individual genetic analysis, it became possible to make a clear-cut distinction between the phenomenon of the lowered gene penetrance and its inherited inactivation. It was shown that low penetrance is a more frequent event which seems to mask the inherited inactivation of the gene. A general scheme of the phenomena studied is proposed. The classical conceptions claiming the existence of a reserve of hereditary variability concern mainly the recessive and codominant mutations. However, the role of dominant and semidominant mutations in the course of functional reconstruction of species may be important. During animal domestication, for example, everyone can see a lot of dominantly inherited characters appearing de novo. D.K. Belyaev's conception about "dormant" gene reserve is of great importance in this connection. Opening of the reserve at a particular evolutionary stage may drastically increase the genetic variability and lead to appearance of evolutionary novelty.

Animals↗
PubMed1987

DNA sequence analysis of the C3H H-2Kk and H-2Dk loci. Evolutionary relationships to H-2 genes from four other mouse strains.

We generated nucleotide sequences for H-2Kk and H-2Dk from the C3H mouse, as well as for a genomic clone of H-2Db, in order to conduct an evolutionary analysis of the H-2 genes from three haplotypes, k, d, and b. H-2Kk from both the C3H and AKR strains, H-2Kd, H-2Kb, H-2Dk, H-2Ld, H-2Dd, H-2Db, and H-2Dp DNA sequences were aligned, and the alignments used to construct phylogenetic trees inferring the evolutionary relationships among the nine genes by two independent methods. Both approaches yielded trees with similar topologies. In addition, the sequence alignments revealed patterns of nucleotide substitutions which implicate both point mutation and recombination in the divergence of the H-2 genes. Future considerations for evolutionary analysis of class I genes are discussed.

Amino Acid Sequence↗
PubMed1980

Population genetic basis of the evolutionary change.

Short introduction is given to population genetic treatment of the evolutionary change. The evolutionary change in the population is based upon the appearance (by mutation or immigration) of new genetic information. The proportion of this new information may increase or decrease by selection and/or random processes. The aid of population genetics is to formulate models in order to understand the essence of the evolutionary change. Some simple deterministic and stochastic single-locus models are quoted from elementary population genetic theory.

Biological Evolution↗
PubMed1994

Antibodies against F1-ATPase alpha-subunit recognize mitochondrial chaperones. Evidence for an evolutionary relationship between chaperonin and ATPase protein families.

Antibodies raised against two synthetic peptides from rat liver F1-ATPase alpha-subunit sequence recognized two main heat-shock proteins from Drosophila (p71 and p56) and rat liver (p74 and p54) cells. One of the antisera showed a 20-fold higher reactivity toward Escherichia coli GroEL chaperonin than toward the alpha-subunit purified from Drosophila. Indirect immunofluorescence microscopy and subcellular fractionation experiments located both mammalian heat-shock proteins in the mitochondria. The recent findings of functional homology between chaperonins and alpha-subunits, together with the unsuspected immunological reactivity of two mitochondrial molecular chaperones toward antisera derived from two different sequence motifs of the alpha-subunit, strongly argue in favor of the existence of an evolutionary relationship between chaperonins and alpha-subunits. The complete sequence alignment of F-type ATPase alpha-subunits and chaperonins revealed the existence of eleven most conserved regions (approximately 30% of each protein sequence) with an overall amino acid identity of 20 +/- 2% and similarity of 39 +/- 4%. A search of protein data bases with three different consensus sequences derived from this alignment identified a significant proportion of proteins belonging only to these two protein families. Since the alpha-subunit protein family is evolutionary related to the other catalytic (A and beta) and regulatory (B) subunits of V- and F-type ATPases, the homology reported herein allowed us to analyze, in the chaperonin sequences, the conservation of critical residues involved in nucleotide binding. These data support the hypothesis that chaperonins and the major subunits of V- and F-type ATPases are evolutionary related.

Amino Acid Sequence↗
PubMed1993

mtDNA sequences suggest a recent evolutionary divergence for Beringian and northern North American populations.

Conventional descriptions of the pattern and process of human entry into the New World from Asia are incomplete and controversial. In order to gain an evolutionary insight into this process, we have sequenced the control region of mtDNA in samples of contemporary tribal populations of eastern Siberia, Alaska, and Greenland and have compared them with those of Amerind speakers of the Pacific Northwest and with those of the Altai of central Siberia. Specifically, we have analyzed sequence diversity in 33 mitochondrial lineages identified in 90 individuals belonging to five Circumpolar populations of Beringia, North America, and Greenland: Chukchi from Siberia, Inupiaq Eskimos and Athapaskans from Alaska, Eskimos from West Greenland, and Haida from Canada. Hereafter, we refer to these five populations as "Circumarctic peoples." These data were then compared with the sequence diversity in 47 mitochondrial lineages identified in a sample of 145 individuals from three Amerind-speaking tribes (Bella Coola, Nuu-Chah-Nulth, and Yakima) of the Pacific Northwest, plus 16 mitochondrial lineages identified in a sample of 17 Altai from central Siberia. Sequence diversity within and among Circumarctic populations is considerably less than the sequence diversity observed within and among the three Amerind tribes. The similarity of sequences found among the geographically dispersed Circumarctic groups, plus the small values of mean pairwise sequence differences within Circumarctic populations, suggest a recent and rapid evolutionary radiation of these populations. In addition, Circumarctic populations lack the 9-bp deletion which has been used to trace various migrations out of Asia, while populations of southeastern Siberia possess this deletion. On the basis of these observations, while the evolutionary affinities of Native Americans extend west to the Circumarctic populations of eastern Siberia, they do not include the Altai of central Siberia.

Alaska↗
PubMed1996

Adolescents' age preferences for dating partners: support for an evolutionary model of life-history strategies.

The tendency for women to prefer older partners, and for men to prefer younger partners, has frequently been explained in terms of socialization to American sex-role norms specifying that men must be older and more powerful than their female partners. However, recent cross-cultural data reveal this same pattern in all societies studied, a finding more in line with an evolutionary life-history model. The evolutionary model assumes that what is attractive to males is not youth, per se, but features related to fertility. This perspective leads to a hypothesis concerning the development of age preferences among adolescents: teenage males should violate the normative pattern shown in adult males and express interest in females older than themselves. 209 teenagers (103 males, 106 females) ranging in age from 12 to 19 were surveyed regarding the age limits they would find acceptable in a dating partner, as well as the age of a dating partner they would find ideally attractive. Although teenage males were willing to date girls slightly younger than themselves, they indicated a much wider range of acceptability above their own ages, and also reported that their ideally attractive partners would be several years older than themselves. Preferences of teenage females were similar in pattern to those of adult females, ranging, on average, from their own age to several years older. When combined with the consistent adult data obtained from numerous cultures, these data suggest the utility of viewing the development of sex differences in mate preference from the perspective of an evolutionary life-history model.

Adolescent↗