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Animals are facing novel 'timescapes' in which the stimuli entraining their daily activity patterns no longer match historical conditions due to anthropogenic disturbance. However, the ecological effects (e.g., altered physiology, species interactions) of novel activity timing are virtually unknown. We reviewed 1328 studies and found relatively few focusing on anthropogenic effects on activity timing. We suggest three hypotheses to stimulate future research: (i) activity-timing mismatches determine ecological effects, (ii) duration and timing of timescape modification influence effects, and (iii) consequences of altered activity timing vary biogeographically due to broad-scale variation in factors compressing timescapes. The continued growth of sampling technologies promises to facilitate the study of the consequences of altered activity timing, with emerging applications for biodiversity conservation. Recent years have seen a growing interest in the role of time in structuring biological patterns and processes. Among nature's most dramatic and universal temporal patterns are the daily activity patterns shown by organisms. Although the endogenous mechanisms (e.g., circadian rhythms) giving rise to such patterns have been researched extensively, ecological aspects of daily activity patterns are now receiving greater attention. Plasticity in daily activity patterns may represent an in situ adaptation to human-mediated stressors such as climate change and urbanization. However, the effects of novel activity timing, which may emerge at multiple levels of biological organization, are poorly understood. We offer hypotheses to catalyze future research on the ecological consequences of altered daily activity timing and discuss approaches that may facilitate such investigations. [ABSTRACT FROM AUTHOR]

Abstract: The spherulitic linear growth rates of a homo-poly(propylene) and a series of propylene–ethylene copolymers, all synthesized with the same type of metallocene catalyst were analyzed. The inter-chain distribution of comonomer content is uniform in these copolymers and the intra-chain distribution adheres to the random behavior. Furthermore, the concentration of stereo and regio defects is constant for all copolymers. Thus, with these polymers it was possible to investigate the influence of ethylene content on the crystallization kinetics, as extracted from their linear growth rates. All iPPs investigated display mixed polymorphic behavior during isothermal crystallization and major emphasis was given to integrate the simultaneous development of the α and γ polymorphs, and their intimate structural relations during growth, in the analysis of the crystallization kinetics. A sharp break in spherulitic growth is found between times domains of mixed α+γ growth and growth of pure γ crystals reflecting a drastic change in growth mechanisms at the point where α development ceases. The rates corresponding to α growth are significantly higher than those characteristics of γ growth. In addition, growth data in the domain of mixed α+γ growth, which, following the structural models for α and γ branching, reflect the growth pattern of α crystals, display a discontinuity in the temperature gradient at the changeover from growth of mixed α+γ to γ dominated growth. This behavior correlates with that found in other systems that undergo a similar extended chain to folded change in crystallization mechanisms. The temperature coefficient of the linear growth rates is analyzed according to regime theory for both domains of growth. The results allow a quantitative framework for discussion of the interfacial free energies of α and γ crystals obtained from this analysis. [Copyright &y& Elsevier]