SUCCESSION AND CLIMAX
Eventually almost everyone has the experience of watching an old neighborhood change. Sometimes we perceive that change for the better, sometimes for the worse, and the perception can have more to do with our individual desires or needs than it does with any qualities inherent in the change itself. For instance, one person might regard a new convenience store and gas station as an eyesore, while another might welcome it as a handy place to buy coffee, gasoline, or other items. Likewise, biological "neighborhoods" change, as when a complete or nearly complete community of living things replaces another. Once again, changes are not necessarily good or bad in any fundamental sense; rather, one community that happens to be better adapted to the changed environment replaces another. Sometimes a stress to the ecosystem brings about a change, such that life-forms that once were adapted to the local environment are no longer. Still, there appears to be a point when a community achieves near perfect adaptation to its environment, a stage in the levels of succession known as climax. This is the situation of old-growth forests, a fact that explains much about environmentalist opposition to logging in such situations.