Human Responses to the Geophysical Daily, Annual and Lunar Cycles

Circadian and Visual Neuroscience, Nuffield Laboratory of Ophthalmology, University of Oxford, Levels 5 & 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford OX3 7BN, UK.
Current Biology (Impact Factor: 9.57). 10/2008; 18(17):R784-R794. DOI: 10.1016/j.cub.2008.07.003
Source: PubMed


Collectively the daily, seasonal, lunar and tidal geophysical cycles regulate much of the temporal biology of life on Earth. The increasing isolation of human societies from these geophysical cycles, as a result of improved living conditions, high-quality nutrition and 24/7 working practices, have led many to believe that human biology functions independently of them. Yet recent studies have highlighted the dominant role that our circadian clock plays in the organisation of 24 hour patterns of behaviour and physiology. Preferred wake and sleep times are to a large extent driven by an endogenous temporal program that uses sunlight as an entraining cue. The alarm clock can drive human activity rhythms but has little direct effect on our endogenous 24 hour physiology. In many situations, our biology and our society appear to be in serious opposition, and the damaging consequences to our health under these circumstances are increasingly recognised. The seasons dominate the lives of non-equatorial species, and until recently, they also had a marked influence on much of human biology. Despite human isolation from seasonal changes in temperature, food and photoperiod in the industrialised nations, the seasons still appear to have a small, but significant, impact upon when individuals are born and many aspects of health. The seasonal changes that modulate our biology, and how these factors might interact with the social and metabolic status of the individual to drive seasonal effects, are still poorly understood. Lunar cycles had, and continue to have, an influence upon human culture, though despite a persistent belief that our mental health and other behaviours are modulated by the phase of the moon, there is no solid evidence that human biology is in any way regulated by the lunar cycle.

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    ABSTRACT: We introduce here the term “River Culture” to delineate an eco-social approach to mitigate the biological and cultural diversity crisis in riverscapes. It is based on the insight that current environmental change endangers both, biological and cultural diversities in rivers and their basins, and those activities to improve ecosystem functions, biodiversity and capacity of the biological species to evolve will have a similarly positive effect on human cultural diversity. “River Culture” has two dimensions, including (a) the influence of the biophysical setting of rivers (specifically, their pulsating flow regimes and their biological features) on the expression of elements of human culture in general and (b) the aspect of “learning from the river” for the development of technologies and management options that are targeted to maintain and improve ecosystem functions and diversity in a more sustainable way. The River Culture approach, as given in this concept and discussion paper, is preliminarily based on five tenets. (1) Reset values and priorities in riverscape management in favor of human wellbeing and a harmonious coexistence of man and riverscape. (2) Live in the rhythm of the waters, i.e. adapt management options in accordance with the hydrological dynamics rather than fighting against them. (3) Transform traditional use of rivers into modern cultural activities and management options. (4) ‘Ecosystem bionics’: by copying survival strategies of flood-pulse adapted organisms novel forms human use can be developed. (5) Make the catchment (river basin) the geographical base unit for all kinds of political decisions in landscape management.
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