Respuesta :
The signs are placed because humans can cause damage to the stability of ecosystems by removing the flowering trees and shrubs.
Ecosystems are self sustaining units in which there is an exchange of materials and energy within itself. There is need for sustainability in ecosystems to ensure that they continue to survive and ultimately to preserve biodiversity.
The sign; "take nothing but pictures, leave nothing but footprints" placed on state forests and parks like Yellowstone National Park which contain varieties of flowering trees and shrubs are there because humans can cause damage to the stability of ecosystems by removing the flowering trees and shrubs.
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