Theory 35/Geometry & Scale/Food webs
Trophic Transfer Needs a Size Gap
The claim
Trophic transfer efficiency is set by the ratio of predator to prey body size, so food chains are limited by size geometry rather than by productivity.
01Mechanism
Capture requires the predator to handle the prey; the size ratio sets handling time and therefore the energy return per unit effort.
02Prediction
Chain length should track the available size ratio.
03Refutation
Chain length tracking productivity would remove the geometric limit.