PREDICTIONS – 10 Years Later - Santa Fe Institute

APPENDIX C
POPULATIONS OF CARS GROW LIKE THOSE OF FRUIT FLIES
APPENDIX FIGURE 3.1 Data points and fitted curves for 2 populations. At the
top, the population of drosophila (fruit flies) under controlled experimental
conditions. At the bottom, the number of registered cars in the United States
refers to the major part of car diffusion in this country following World War II. ∗
∗ The top graph was first published by R. Pearl and S.L.Parker, American Naturalist,
vol. 55 (1921): 503; vol. 56, (1922): 403, as cited by Alfred J. Lotka, Elements of
Physical Biology, (Baltimore, MD: Williams & Wilkins Co., 1925). The data for the
bottom graph come from Statistical Abstract of the United States, U.S. Department
of Commerce.
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