2006-11-20 12:22:23 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Biology
Each ecosystem has what is called a "carrying capacity" for the organisms. This is where birth rate = deaths.
This is because organism's grow in number until the demand or limit of one (or more) factors for life become exceeded.
Some factors are things like water, living space, nutrient source (food) and waste build up.
Populations can exceed the carrying capacity for a short time but eventually the limit of the environment brings the population back down.
2006-11-20 13:00:10 · answer #1 · answered by Beef 5 · 0⤊ 0⤋
Because they would have to have an indefinate food supply to support themselves. And some of the organisms eventually have to die, so while part of a group population of organisms is growing, another part is shrinking.
2006-11-20 12:25:15 · answer #2 · answered by badkitty1969 7 · 1⤊ 1⤋