Why fishing less gave the Adriatic more sharks: foxes, rabbits and a loop
30seconds
When fishing slowed during the First World War, the Adriatic catch held a bigger share of sharks and rays, not a smaller one. Mathematician Vito Volterra explained it with two equations.
Rabbits breed, foxes eat rabbits, foxes starve without them. That is enough to make both populations rise and fall in an endless loop. Drag the populations around, add foxes, and turn up the fishing to see why doing less can favour the hunters.
Deep dive · 3 min
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