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No. 78: Nov-Dec 1991

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More light, more fight

Hostilities correlating with the number of hours of sunlight Using 2,131 acts of histility recorded over the last 3500 years, G. Schreiber et al have shown that these conflicts did not begin at random. Instead onsets of hostility are nicely correlated with the number of hours of sunlight in the day each war began.

"In the Northern Hemisphere, latitudes 30-60 N., the annual rhythm in the opening dates of wars shows a peak in August and a nadir in January (a in the figure). An inverse pattern in the annual rhythm of wars with a peak in December-February and a nadir in July was found in the Southern Hemisphere latitudes 30-60 S (c in the figure)....The results in the Northern Hemisphere suggest that there is a phase-shift of about one month between the two rhythms. We found a constant rate of acts of hostility throughout the year around the line of the Equator (b in the figure)."

(Schreiber, Gabriel, et al: "Rhythms of War," Nature, 352:574, 1991.)

Comment. From the curves, it appears that inhabitants of the Northern Hemisphere are about 20 times more bellicose than those below the Equator (a population effect?).

Reference. The cyclicity of human behavior requires several categories in the catalog volume Biological Anomalies: Humans I, notably BHB8. Ordering information here.

From Science Frontiers #78, NOV-DEC 1991. 1991-2000 William R. Corliss

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  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987