2003/05/12 by Hiro-Sato Niwa
Biochemistry, Genetics and Molecular Biology · Economics, Econometrics and Finance · Environmental Science · Physics and Astronomy · Social Sciences · #Complex Systems and Time Series Analysis #Ecosystem dynamics and resilience #Evolutionary Game Theory and Cooperation #cond-mat.stat-mech #q-bio.PE
paper · pdf · doi:10.1016/s0022-5193(03)00192-9
published as J. Theor. Biol. 224 (2003) 451-457 · 19 pages,9 figures, to appear in J. Theor. Biol
arxiv created 2003/05/12 · openalex publication_date 2003/09/12 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
There has been some confusion concerning the animal group-size: an exponential distribution was deduced by maximizing the entropy; lognormal distributions were practically used; a power-law decay with exponent 3/2 was proposed in physical analogy to aerosol condensation. Here I show that the animal group-size distribution follows a power-law decay with exponent 1, and is truncated at a cut-off size which is the expected size of the groups an arbitrary individual engages in. An elementary model of animal aggregation based on binary splitting and coalescing on contingent encounter is presented. The model predicted size distribution holds for various data from pelagic fishes and mammalian herbivores in the wild.