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Involution of Simple and Complex Reaction Times Among People Aged Between 21 and 80 - The Results of Computer Tests

100%
Jaworski J., Tchórzewski D., Bujas P.
Human Movement
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2011
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vol. 12
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issue 2
153-158
EN
Purpose. The aim of this case study is to define the involution of simple and complex reaction times in groups of adult men and women. Basic procedure. The tests were carried out during the years 2007-2008 among 128 men and 136 women aged between 21 and 80. Those examined were divided into three groups according to their calendar age. In order to define the meaning of differences of the analyzed reaction time between the results of the three age groups, the analysis of variance (ANOVA) method for independent attempts was used. Additionally, normalized differences between the groups as well as indices of sexual dimorphism were defined. Main findings. Among both men and women, gradual deterioration of reaction time performance with age can be observed. The scale of normalized differences shows that the most distinct differences are noticed between the first and the third group. They amount up to 1.3 of the standard deviation in men and up to 1.7 in women. Conclusions. The results derived from the following study confirm a long period of relative stabilization for all simple and complex reaction times among both genders. Significant involution of reaction times can be observed for all analyzed features only after the age of 55. Indices of sexual dimorphism indicate that men gain better results in all age groups. Indices of sexual dimorphism diminish with age.
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Sexual selection in the Swallow Hirundo rustica - A review

75%
Bańbura J., University of Łódź D. o. E. Z. a. E. B.
Acta Universitatis Lodziensis. Folia Biologica et Oecologica
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2005
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vol. 2
EN
Darwinian theory of sexual selection and its development up to the present state of knowledge are sketched. The most important results of empirical studies on sexual selection in the Swallow Hirundo rustica are reviewed. The Swallow is a socially monogamous, slightly sexually dimorphic avian species. Long tail streamers are considered as sexual ornaments of males. Female preference for long and symmetric male tails has been inferred on both observational and experimental grounds. Experimental elongation of the tail causes short-term benefits and long-term costs in male reproductive performance. Behavioural consequences of sexual selection acting in the Swallow are discussed. An aerodynamic role of male tail streamers is also considered.
3
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Discovery of Swimming Males of Paratanaoidea (Tanaidacea)

75%
Błażewicz-Paszkowycz M., Jennings R. M., Jeskulke K., Brix S.
Polish Polar Research
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2014
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issue 2
4
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Changes in Body Build of AWF Students 1967-2008. Can a Secular Trend be Observed?

75%
Stachoń A., Burdukiewicz A., Pietraszewska J., Andrzejewska J.
Human Movement
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2012
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vol. 13
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issue 2
109-119
EN
Purpose. Previous research on intergenerational changes in body build has focused on body height and mass. The aim of this study was to determine both the direction and sexual dimorphism of secular changes in body build by using a sample population of students attending the University School of Physical Education (AWF) in Wrocław, Poland. Methods. The anthropometric data used in this study were collected every year from 1967 to 2008 and included a sample size of 4688 males and 3922 females. The subjects were analyzed for changes in somatotype by use of Sheldon's method, as modified by Heath and Carter. Basic statistical analysis for significance and post-hoc tests were used to analyze the data with Statistica 9.0 software. The data were then converted in Excel 2003 into chart form to analyze the direction of changes. Results. Analysis of the successive classes of male and female subjects during the 40-year period under study revealed a number of different directional changes in the mean values of body height, mass and the level of body build components. Trend lines, calculated by the mean values of five-year intervals, indicated an increasing tendency in both body height and mass in the two genders. Mesomorphy was found to be the largest factor of body build composition of females and males. Throughout the entire analyzed period, the endomorphy of males was significantly lower in comparison to females. In women, the level of fatness was similar to their level of musculature, but during the last several years the observed level of muscle in the students exceeded their fatness level. Ectomorphy happened to be the most stable component of both sexes. Conclusions. Analysis on the male and female sample population revealed a constant increase in body mass and height in successive generations. In female subjects, intergenerational changes were found to be characterized by a decrease in endomorphy and an increase in ectomorphy, while the level of mesomorphy remained at a similar level. In men, a secular trend was visible with an increase in mesomorphy, while the levels of endomorphy and ectomorphy stayed constant.
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