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Wealth Inequality Among Snails

The economics of snails—specifically, what one might call “the economics of the shell game”—gets some data and hard thought in a new study.

A Comparison of Wealth Inequality in Humans and Non-Humans,” Ivan D. Chase, Raphael Douady, and Dianna K. Padilla, Physica A: Statistical Mechanics and its Applications, 2019, 122962. The authors, at Stony Brook University, explain:

“Inequality in the distribution of material resources (wealth) occurs widely across human groups…. Here we present the first description of inequality in material resources in an animal population: the distribution of gastropod (snail) shells inhabited by the hermit crab Pagurus longicarpus. We find that the shell distribution for the crabs strongly resembles the characteristic form of wealth distribution in human groups. The amount of inequality in the crabs is more than that in some small-scale human groups but less than that in nations.”

Improbable Research