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Title: Synchrony affects Taylor’s law in theory and data
Taylor’s law (TL) is a widely observed empirical pattern that relates the variances to the means of groups of nonnegative measure- ments via an approximate power law: variance_g ≈ a × mean_g^b, where g indexes the group of measurements. When each group of measurements is distributed in space, the exponent b of this power law is conjectured to reflect aggregation in the spatial dis- tribution. TL has had practical application in many areas since its initial demonstrations for the population density of spatially dis- tributed species in population ecology. Another widely observed aspect of populations is spatial synchrony, which is the tendency for time series of population densities measured in different loca- tions to be correlated through time. Recent studies showed that patterns of population synchrony are changing, possibly as a con- sequence of climate change. We use mathematical, numerical, and empirical approaches to show that synchrony affects the validity and parameters of TL. Greater synchrony typically decreases the exponent b of TL. Synchrony influenced TL in essentially all of our analytic, numerical, randomization-based, and empirical examples. Given the near ubiquity of synchrony in nature, it seems likely that synchrony influences the exponent of TL widely in ecologically and economically important systems.  more » « less
Award ID(s):
1714195 1442595
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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