The Biology of Polluted Water
In an orchard or meadow the authors usually find grasshoppers, mice, certain birds, and butterflies; if a hunter returns from his trip with game bag filled chiefly with ducks or other waterfowl they certainly know that his field of operations has been the marshes or streams rather than the hardwood forest.
Abstract
Most organisms react to their environment. Given, a suitable environment, and the organisms thrive; unsuitable, and they depart, or perhaps die out. For instance squirrels will thrive in a forest where nuts are plentiful and certain other conditions are favorable. But if the nut-bearing trees be removed, or if enemies become too numerous and effective, the squirrels will depart or will be killed off. Given, a certain environment, a keen observer will enumerate the prevailing forms of life to be found there; or if a certain assemblage of life forms be named, the same observer will state the approximate environment in which they were found. Thus in an orchard or meadow we usually find grasshoppers, mice, certain birds, and butterflies. And if a hunter returns from his trip with game bag filled chiefly with ducks or other waterfowl we certainly know that his field of operations has been the marshes or streams rather than the hardwood forest.