Parameters of psychophysiological adaptation to the academic process at a faculty of physical training in students specializing in different sports

The features of psychophysiological adaptation to learning at a physical training institute were studied in students of the faculty of physical training who specialized in different sports. The character of adaptive reorganizations in students involved in cyclic sports reflected the correspondence of the type of functional constitution to the sport specialization. Adaptation to the academic process in students involved in acyclic sports or sport games was accompanied by autonomic regulation strain, which was attributed to the inadequacy of physical loads to the state of the body. The adaptive capabilities of the students of the faculty of physical training were shown to depend not only on the specific character of the academic process at the faculty but also on the correspondence of the individual typological features to the chosen specialization.Translated from Fiziologiya Cheloveka, Vol. 31, No. 1, 2005, pp. 77–81.Original Russian Text Copyright © 2005 by Kazin, Varich.     

Walking the Walk to Teach the Talk: Implementing Ancestral Lifestyle Strategies as the Newest Tool in Evolutionary Studies

The learning of evolutionary theory typically takes place in the classroom or laboratory. Students of these traditional approaches often leave with the notion that applications of evolutionary theory have little bearing on their lives. The Evolutionary Studies Consortium (EvoS; ) has been extremely successful in overcoming these barriers and demonstrating the bridges across academic areas that can be created with the principles of evolution as a guide. While this is a fantastic means through which to educate students about the intricacies of evolution, we believe that the full potential of this approach has yet to be realized. Applications beyond strict academic contexts are still waiting to be mined. Here, we outline an approach that proposes the implementation of a nutrition and physical fitness program, alongside classroom pedagogy, as a means of helping students learn about evolution and how it can be used to increase their own quality of life.     

Hybridization and adaptive radiation

Whether interspecific hybridization is important as a mechanism that generates biological diversity is a matter of controversy. Whereas some authors focus on the potential of hybridization as a source of genetic variation, functional novelty and new species, others argue against any important role, because reduced fitness would typically render hybrids an evolutionary dead end. By drawing on recent developments in the genetics and ecology of hybridization and on principles of ecological speciation theory, I develop a concept that reconciles these views and adds a new twist to this debate. Because hybridization is common when populations invade new environments and potentially elevates rates of response to selection, it predisposes colonizing populations to rapid adaptive diversification under disruptive or divergent selection. I discuss predictions and suggest tests of this hybrid swarm theory of adaptive radiation and review published molecular phylogenies of adaptive radiations in light of the theory.     

The functional prognosis of physical working ability under conditions of extreme high altitude

The physical performance of climbers, those making high-altitude ascensions up to 8000 m, without additional oxygen was measured. Some functional criteria of the organism adaptation to exhausting physical loading at the high altitudes were selected. It was established that the forecasting of a successful ascension could be improved if the potential maximal oxygen uptake was added to the standard definition parameters of aerobic metabolism such as the maximal oxygen uptake and anaerobic threshold of oxygen uptake. The potential maximal oxygen uptake is considered to be the parameter of maximal oxygen uptake reserve growing in condition of realization of adaptive reaction to hypoxia.     

Rapid adaptive divergence of life-history traits in response to abiotic stress within a natural population of a parthenogenetic nematode

Sexual reproduction is acknowledged to facilitate adaptation to novel environments while asexual eukaryotes are often regarded as having low adaptive potential. This view has been challenged in a number of studies, but the adaptive potential of asexual populations in the field is poorly documented. We investigated the response of natural populations of the parthenogenetic nematode Acrobeloides nanus to imposed divergent selective pressures. For this purpose, we employed a replicated evolution experiment in the field. After 20 years of evolution under abiotic stress and control conditions, life-history traits were assessed in reaction norm- and reciprocal transplant experiments. Both these experiments indicated adaptive divergence within the population of A. nanus. Namely, the transplant experiment demonstrated that in the stressed soil environment, body growth rate was more reduced in the nematodes originating from the control treatment. In the reaction norm experiment, survival and reproduction were higher under test conditions corresponding to the native environment of the nematodes. The differences in the analysed traits are discussed in the context of life-history theory. Overall, our results strongly support high adaptive potential of A. nanus and suggest that population structure and distribution of asexual species is shaped by local adaptation events.     

A Model of Relationships between Different Systems of Characters and the Adaptation Potential of the Body in Early Adulthood

Relationships of the adaptation potential with sets of somatic, functional, and dermatoglyphic parameters; personality traits; and polymorphisms of certain genes (FTO, DAT1, and VDR) were studied using data from anthropological examination and psychological testing of 655 healthy students aged 17–25 years from various higher education schools. The study employed two methods that allow premorbid diagnosis of the functional (physical) condition and adaptation and are recommended for large-scale preventive examinations in adults. The methods address the functional status according to Pirogova et al. and the adaptation potential according to Bayevsky et al. An original model of relationships between different sets of traits (somatic, functional, dermatoglyphic, and personality traits) and the adaptive potential in early adulthood was proposed on the basis of significant canonical correlations and Pearson’s contingency coefficients with due regards to the effects that the gene polymorphisms exert on the formation of trait sets.     

The adaptive significance of autumn leaf colours

Recently W.D. Hamilton and colleagues proposed a provocative new theory to explain the adaptive significance of autumnal leaf colours. They suggested that these colours were signals produced by the trees to warn potential insect herbivores of their defensive ability and tested this theory by an analysis of data on aphid species richness on different tree species. Here we argue that the principal assumptions of their theory do not match current knowledge of plant pigment biochemistry and aphid ecology. We therefore present further adaptive explanations for autumn leaf colours and suggest alternative reasons for the reported relationship between tree leaf colour and aphid species richness.     

HOW STABLE ‘SHOULD’ EPIGENETIC MODIFICATIONS BE? INSIGHTS FROM ADAPTIVE PLASTICITY AND BET HEDGING

Although there is keen interest in the potential adaptive value of epigenetic variation, it is unclear what conditions favor the stability of these variants either within or across generations. Because epigenetic modifications can be environmentally sensitive, existing theory on adaptive phenotypic plasticity provides relevant insights. Our consideration of this theory suggests that stable maintenance of environmentally induced epigenetic states over an organism's lifetime is most likely to be favored when the organism accurately responds to a single environmental change that subsequently remains constant, or when the environmental change cues an irreversible developmental transition. Stable transmission of adaptive epigenetic states from parents to offspring may be selectively favored when environments vary across generations and the parental environment predicts the offspring environment. The adaptive value of stability beyond a single generation of parent–offspring transmission likely depends on the costs of epigenetic resetting. Epigenetic stability both within and across generations will also depend on the degree and predictability of environmental variation, dispersal patterns, and the (epi)genetic architecture underlying phenotypic responses to environment. We also discuss conditions that favor stability of random epigenetic variants within the context of bet hedging. We conclude by proposing research directions to clarify the adaptive significance of epigenetic stability.     

The Adaptive Potential of Adolescents in the North and Its Relation to Interhemispheric Functional Asymmetry

Sensorimotor asymmetry, physical development, annual increments in the body size, functional state and adaptive potential as expressed by circulatory indices, life index, and functional test results were evaluated in 142 healthy Nenets adolescents from a boarding school and 60 healthy Russian pupils. Dextral and sinistral phenotypes were represented unequally in the children of both groups; the former was more common among the Russians. The subjects' adaptive capacities depended on their sex and the predominance of particular signs of interhemispheric functional asymmetry.     

Peculiarities of hemostasis reactivity under stress load in persons with different degree of physical training

Healthy young persons with different degrees of physical training have been impacted with exposure to a stress (a single physical exercise). It caused unidirectional hypercoagulative shifts and activation of anticoagulant and fibrinolytic blood systems. It was shown that changes of the untrained individuals' haemostatic parameters could be adjusted with adaptogen preliminary administration. The adaptogen administration in trained individuals resulted in disadaptive shifts in the haemostatic system. These contradictory changes indicate different levels of subject's adaptive potential.     

A theory of speech perception

A theory of speech perception based on evolutionary adaptive postulates is suggested. The principles are grouped around two categories: (a) the physical properties of the stimulus energy and its distributions in the environment; (b) the tendency of the sensory powers to become optimum in order to aid the survival of the species. The construction of the theory and the experiments performed to test its basic predictions are summarized. The theory is examined rather thoroughly with respect to basic vowel space. A line of generalization for the treatment of consonants is indicated.     

Quantifying the Adaptive Cycle

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term (1994–2011) data and multivariate analysis of community structure to assess key components of the adaptive cycle. Specifically, we tested predictions about: reorganisation: spring and summer blooms comprise distinct community states; conservatism: community trajectories during individual adaptive cycles are conservative; and adaptation: phytoplankton species during blooms change in the long term. All predictions were supported by our analyses. Results suggest that traditional ecological paradigms such as phytoplankton successional models have potential for moving the adaptive cycle from a metaphor to a framework that can improve our understanding how complex systems organize and reorganize following collapse. Quantifying reorganization, conservatism and adaptation provides opportunities to cope with the intricacies and uncertainties associated with fast ecological change, driven by shifting system controls. Ultimately, combining traditional ecological paradigms with heuristics of complex system dynamics using quantitative approaches may help refine ecological theory and improve our understanding of the resilience of ecosystems.     

Inter-annual and spatial climatic variability have led to a balance between local fluctuating selection and wide-range directional selection in a perennial grass species

Background and AimsThe persistence of a plant population under a specific local climatic regime requires phenotypic adaptation with underlying particular combinations of alleles at adaptive loci. The level of allele diversity at adaptive loci within a natural plant population conditions its potential to evolve, notably towards adaptation to a change in climate. Investigating the environmental factors that contribute to the maintenance of adaptive diversity in populations is thus worthwhile. Within-population allele diversity at adaptive loci can be partly driven by the mean climate at the population site but also by its temporal variability.MethodsThe effects of climate temporal mean and variability on within-population allele diversity at putatively adaptive quantitative trait loci (QTLs) were evaluated using 385 natural populations of Lolium perenne (perennial ryegrass) collected right across Europe. For seven adaptive traits related to reproductive phenology and vegetative potential growth seasonality, the average within-population allele diversity at major QTLs (HeA) was computed.Key ResultsSignificant relationships were found between HeA of these traits and the temporal mean and variability of the local climate. These relationships were consistent with functional ecology theory.ConclusionsResults indicated that temporal variability of local climate has likely led to fluctuating directional selection, which has contributed to the maintenance of allele diversity at adaptive loci and thus potential for further adaptation.     

Functional responses of adaptive consumers and community stability with emphasis on the dynamics of plant-herbivore systems

A comparatively recent focus in consumer–resource theory has been the examination of whether adaptive foraging by consumers, manifested through the functional response, can stabilize consumer–resource dynamics. We offer a brief synthesis of progress on this body of theory and identify the conditions likely to lead to stability. We also fill a gap in our understanding by analysing the potential for adaptively foraging herbivores, which are constrained by time available to feed and digestive capacity, to stabilize dynamics in a single-herbivore/two-plant resource system. Because foraging parameters of the adaptive functional response scale allometrically with herbivore body size, we parameterized our model system using published foraging data for an insect, a small mammal and a large mammal spanning four orders of magnitude in body size, and examined numerically the potential for herbivores to stabilize the consumer–resource interactions. We found in general that the herbivore–plant equilibrium will be unstable for all biologically realistic herbivore population densities. The instability arose for two reasons. First, each herbivore exhibited destabilizing adaptive consumer functional responses (i.e. density-independent or inversely density-dependent) whenever they selected a mixed diet. Secondly, the numerical response of herbivores, based on our assumption of density-independent herbivore population growth, results in herbivores reaching densities that enable them to exploit their resource populations to extinction. Our results and those of studies we reviewed indicate that, in general, adaptive consumers are unlikely to stabilize the dynamics of consumer–resource systems solely through the functional response. The implications of this for future work on consumer–resource theory are discussed.     

What Actually Confers Adaptive Capacity? Insights from Agro-Climatic Vulnerability of Australian Wheat

Vulnerability assessments have often invoked sustainable livelihoods theory to support the quantification of adaptive capacity based on the availability of capital—social, human, physical, natural, and financial. However, the assumption that increased availability of these capitals confers greater adaptive capacity remains largely untested. We quantified the relationship between commonly used capital indicators and an empirical index of adaptive capacity (ACI) in the context of vulnerability of Australian wheat production to climate variability and change. We calculated ACI by comparing actual yields from farm survey data to climate-driven expected yields estimated by a crop model for 12 regions in Australia’s wheat-sheep zone from 1991–2010. We then compiled data for 24 typical indicators used in vulnerability analyses, spanning the five capitals. We analyzed the ACI and used regression techniques to identify related capital indicators. Between regions, mean ACI was not significantly different but variance over time was. ACI was higher in dry years and lower in wet years suggesting that farm adaptive strategies are geared towards mitigating losses rather than capitalizing on opportunity. Only six of the 24 capital indicators were significantly related to adaptive capacity in a way predicted by theory. Another four indicators were significantly related to adaptive capacity but of the opposite sign, countering our theory-driven expectation. We conclude that the deductive, theory-based use of capitals to define adaptive capacity and vulnerability should be more circumspect. Assessments need to be more evidence-based, first testing the relevance and influence of capital metrics on adaptive capacity for the specific system of interest. This will more effectively direct policy and targeting of investment to mitigate agro-climatic vulnerability.     

The Impact of Coping Flexibility on the Risk of Depressive Symptoms

Objective

According to the dual-process theory, coping flexibility is defined as the ability to produce and implement a new coping strategy in place of an ineffective coping strategy. Specifically, coping flexibility includes two processes: evaluation coping and adaptive coping. Evaluation coping refers to sensitivity to feedback about the efficacy of a coping strategy, and adaptive coping involves the willingness to implement alternative coping strategies. The coping flexibility hypothesis (CFH) postulates that more flexible coping will be associated with more adaptive outcomes; importantly, there are numerous theories and studies that support the CFH. The main purpose of this study was to test the CFH based on dual-process theory.

Methods

A total of 1,770 Japanese college students participated and, completed a set of questionnaires that measured coping flexibility (evaluation coping and adaptive coping) and depressive symptoms. Depressive symptoms were measured via the Center for Epidemiologic Studies Depression Scale.

Results

The proportions of women and men who reported depressive symptoms were 58.69% (95% CIs [55.74, 61.66]) and 54.17% (95% CIs [50.37, 57.95]), respectively when a cut-off score of 16 on the CES-D was used. A multivariable logistic regression analysis revealed that evaluation coping (OR = 0.86, 95% CIs [0.83, 0.0.89]) and adaptive coping (OR = 0.91, 95% CIs [0.88, 0.93]) were significantly associated with lower levels of depressive symptoms.

Conclusion

The results of the present study indicated that the CFH based on dual-process theory was supported in a Japanese sample.     

中国学生体质发育的生长加速及与日本学生的比较

在 1 98 5年和 1 995年国家教委、国家体委、卫生部、国家民委、国家科委共同领导和组织的全国性的学生体质健康调查基础上 ,及本世纪 30年代起个别省城 (北京市、天津市、上海市、丹阳市 (县 )、南京市、辽宁省、黑龙江省及山东省 )学生的体质调查资料基础上 ,作者经数理统计 ,并就我国学生的体质发育状况和生长加速问题对汉族学生和少数民族学生分别加以分析讨论 ,从而了解了我国学生体质发育的现状 ;经与近邻的日本国的学生的体质发育和生长加速状况比较后也找到了差距。
我国学生的体质发育水平目前虽有些不足 ,但我国学生的体质发育指标的生长增长值比日本国学生在身高指标上 ,男学生大2.10cm,女学生大1.65cm;在体重指标上 ,男学生大2.22kg,女学生大1.54kg,身高和体重指标相对日本国而言都仍呈较大的增长趋势 ,存在发展潜力 ,我国学生的体质定将有提高的可能。但胸围指标与身高和体重指标相比 ,除城市男女学生增长值还较大外 ,乡村学生的增长值却为偏低 ,这将影响我国学生的身体素质 ,影响整体生长发育水平的提高。这些将为我国有关部门制定方针政策和实施措施提供可靠的科学依据。我国的经济正在迅速发展 ,对我国学生的营养已采取了积极的措施加以改善和提高 ,并加强了学生的体育锻炼,中小学学生的学业负担也正在减轻,因此,对我国学生体质发育的促进的效果是可能达到的。     

Eco‐evolutionary dynamics in a coevolving host–virus system

Eco‐evolutionary dynamics have been shown to be important for understanding population and community stability and their adaptive potential. However, coevolution in the framework of eco‐evolutionary theory has not been addressed directly. Combining experiments with an algal host and its viral parasite, and mathematical model analyses we show eco‐evolutionary dynamics in antagonistic coevolving populations. The interaction between antagonists initially resulted in arms race dynamics (ARD) with selective sweeps, causing oscillating host–virus population dynamics. However, ARD ended and populations stabilised after the evolution of a general resistant host, whereas a trade‐off between host resistance and growth then maintained host diversity over time (trade‐off driven dynamics). Most importantly, our study shows that the interaction between ecology and evolution had important consequences for the predictability of the mode and tempo of adaptive change and for the stability and adaptive potential of populations.     

The causal theory of the resting potential of cells

In this pedagogical article the causal theory of the resting potential of cells is presented, which for given extracellular ion concentrations predicts the intracellular ones simultaneously with the resting potential. In addition to the Na, K-pump, fixed charges on the membrane surfaces are taken into account. The equation determining the resting potential in the causal theory suggests a new explanation of the genesis of the resting potential. The usual criterion for an ion pump to be electrogenic is not relevant for the whole of the resting potential, and may therefore be misleading. The physical meaning of the Goldman-Hodgkin-Katz formula for the membrane potential as a diffusion potential is also explained and tested with numbers for the giant axon of the squid. A significant discrepancy between theory and experiment is found which calls for an experimental re-examination of the constitutive equations for passive potassium and sodium currents.     

Evolution to alternative levels of stable diversity leaves areas of niche space unexplored

One of the oldest and most persistent questions in ecology and evolution is whether natural communities tend to evolve toward saturation and maximal diversity. Robert MacArthur’s classical theory of niche packing and the theory of adaptive radiations both imply that populations will diversify and fully partition any available niche space. However, the saturation of natural populations is still very much an open area of debate and investigation. Additionally, recent evolutionary theory suggests the existence of alternative evolutionary stable states (ESSs), which implies that some stable communities may not be fully saturated. Using models with classical Lotka-Volterra ecological dynamics and three formulations of evolutionary dynamics (a model using adaptive dynamics, an individual-based model, and a partial differential equation model), we show that following an adaptive radiation, communities can often get stuck in low diversity states when limited by mutations of small phenotypic effect. These low diversity metastable states can also be maintained by limited resources and finite population sizes. When small mutations and finite populations are considered together, it is clear that despite the presence of higher-diversity stable states, natural populations are likely not fully saturating their environment and leaving potential niche space unfilled. Additionally, within-species variation can further reduce community diversity from levels predicted by models that assume species-level homogeneity.