10 Percent Rule

10 Percent Rule Definition

Imagine you receive a paycheck, but after taxes, bills, and expenses, only a small portion is left for savings. This is similar to the 10 percent rule in ecology, where only about 10% of energy is transferred from one trophic level to the next as you move up the food chain. Just as most of your paycheck is consumed by necessary expenditures, most of the energy within an ecosystem is used up for survival and maintenance, leaving only a small fraction to be stored or passed on to the next level, much like your savings.

Practice Version

10 Percent Rule Definition

10 Percent Rule: Ecological law that states that 10 of energy is passed from one trophic level to the next. 10 percent rule. The 10 percent rule means that when energy moves from one level of a food chain to the next, only about 10 of the energy is given to the next level, while the rest is lost mostly as heat.