Easter Island is a great (and terrifying) example. If you know anything about the island, you'll know two things: it's barren and treeless, and it has all those statues. It actually used to be heavily forested, and contained some of the largest palm trees in the world. However, to make way for agriculture and continue the construction of those famous faces, the forests were eventually cleared, leading to soil erosion, famine, and a massive decrease in indigenous population.
As much as we like to think that humans are sensible and that we can stop ourselves before we do any great harm, thinking about this: there came a day where someone cut down the last tree on Easter Island. Someone, who probably grew up with memories of how it used to be or with knowledge of the islands previous grand forests (and the problems that had arisen due to its destruction), made the decision to cut down that single survivor.
Humanity's fucked, basically.