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Performance Abilities (performance + ability)
Selected AbstractsHorn size predicts physical performance in the beetle Euoniticellus intermedius (Coleoptera: Scarabaeidae)FUNCTIONAL ECOLOGY, Issue 4 2005S. P. LAILVAUX Summary 1In many animals, the size of secondary sexual ornaments is known to be related to the probability of victory in fights between males, and hence to fighting ability. However, few studies have attempted to link fighting ability to any physical performance measures. 2Here we show that horn size in the dung beetle Euoniticellus intermedius accurately predicts two types of whole-organism performance, independent of body size, that are likely to play an important role in male contests: the force required to pull a beetle out of a tunnel, and the distance the beetle was able to run before exhaustion (maximum exertion). 3Body length is also a statistically significant predictor of pulling force, but not of exertion, suggesting that horn size is a more reliable predictor of performance than body size alone, a result that is consistent with a previous finding that horn size becomes more important in determining victory in male,male contests as body size increases. 4This study is the first to establish direct links between whole-organism performance abilities, male armaments and fighting ability in the same species. Our findings suggest that physiological performance capacities are important factors underlying the evolution of signal expression in E. intermedius, and should be considered in future studies of the evolution of animal signalling. [source] Intellectual abilities and white matter microstructure in development: A diffusion tensor imaging studyHUMAN BRAIN MAPPING, Issue 10 2010Christian K. Tamnes Abstract Higher-order cognitive functions are supported by distributed networks of multiple interconnected cortical and subcortical regions. Efficient cognitive processing depends on fast communication between these regions, so the integrity of the connections between them is of great importance. It is known that white matter (WM) development is a slow process, continuing into adulthood. While the significance of cortical maturation for intellectual development is described, less is known about the relationships between cognitive functions and maturation of WM connectivity. In this cross-sectional study, we investigated the associations between intellectual abilities and development of diffusion tensor imaging (DTI) derived measures of WM microstructure in 168 right-handed participants aged 8,30 years. Independently of age and sex, both verbal and performance abilities were positively related to fractional anisotropy (FA) and negatively related to mean diffusivity (MD) and radial diffusivity (RD), predominantly in the left hemisphere. Further, verbal, but not performance abilities, were associated with developmental differences in DTI indices in widespread regions in both hemispheres. Regional analyses showed relations with both FA and RD bilaterally in the anterior thalamic radiation and the cortico-spinal tract and in the right superior longitudinal fasciculus. In these regions, our results suggest that participants with high verbal abilities may show accelerated WM development in late childhood and a subsequent earlier developmental plateau, in contrast to a steadier and prolonged development in participants with average verbal abilities. Longitudinal data are needed to validate these interpretations. The results provide insight into the neurobiological underpinnings of intellectual development. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [source] Perceptual, motor and cognitive performance components of Bedouin children in IsraelOCCUPATIONAL THERAPY INTERNATIONAL, Issue 4 2000Shula Parush PhD Abstract The purpose of this study was to evaluate the perceptual, motor and cognitive performance abilities of Bedouin children as compared with mainstream Israeli children of the same age. The study population comprised two age groups (6,8 year olds and 10,12 year olds) living in two different types of settlements (rural and town). Participants included 20 children in each group. The Test of Visual-Perceptual Skills (TVPS), the Developmental Test of Visual-Motor Integration (VMI), selected subtests from the Bruininks-Oseretsky Test of Motor Proficiency and the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) were used. Older participants in all three groups performed better than the younger subjects. There were no significant differences between the two Bedouin groups in either age category. The mainstream Israeli subjects scored significantly higher than the two Bedouin groups on most variables tested. The lack of differences between the two Bedouin groups may indicate that the transition from nomadic communities to urban communities is mainly external and has not caused a significant change in perception, perceptual-motor and cognitive performance abilities. The results of this study may be used as a base for developing preventive intervention programmes to meet the specific needs of Bedouin children. A limitation of this study was the classification of the Bedouin population according to their dwelling place and not according to their sociodemographic background, such as parents' economic status, parents' education and so on. Recommendations for future research include expanding the number of participants, including children from additional rural schools of various distant tribes and incorporating more detailed cognitive assessments. Copyright © 2000 Whurr Publishers Ltd. [source] Do alternate escape tactics provide a means of compensation for impaired performance ability?BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010KIMBERLY A. MILLER Whole-animal performance abilities can facilitate the avoidance of predation and consequently influence fitness, but determining the functional significance of antipredation tactics is difficult without understanding how alternate predator escape strategies are related. We measured maximal sprint speed and dive duration in the semi-aquatic skink Oligosoma suteri to determine how morphology and behaviour influence these alternate predator escape techniques and the relationship between the two measures. Gravid females and juveniles ran significantly slower, but had equivalent or longer dive durations than males and nongravid females. The two performance measures were not influenced by the same morphological and behavioural traits, and were not correlated among individuals. Thus, individuals that are poor sprinters because of their state (e.g. gravid or tail-less individuals) would have a greater likelihood of successful escape by adopting an alternate escape strategy. For species that use multiple strategies for the same function, quantifying selection on whole-animal performance will be difficult. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 241,249. [source] |