Van Westendorp Price Sensitivity Meter

Biological Parallel

Foraging animals implicitly map four price thresholds: too cheap to be worth eating (tiny insects with negligible calories), good value (optimal prey size), expensive but acceptable (large prey requiring pursuit), and prohibitively expensive (prey too dangerous or energetically costly). Shrews, with extreme metabolic rates, continuously calibrate these thresholds—they must eat every 2-3 hours or starve, making their "acceptable range" narrower than bears preparing for hibernation. Different metabolic demands create different price sensitivity windows for identical food sources.