A global catastrophic risk is a hypothetical future event with the potential to inflict serious damage to human well-being on a global scale. Some such events could destroy or cripple modern civilization. Other, even more severe, scenarios threaten permanent human extinction. These are referred to as existential risks.(is my answer is good give me best)

I think that the simplest answer is that we wouldn’t last very long at all!! We rely on natural resources for our food, drink, and pretty much everything else we use in our lives. Without those resources, our planet would probably be a lot more like Mars.

It’s an important point that your question brings up, that we need to look after our natural resources not just because of the fact they’re pretty, or that other animals use them, but that we also rely on them to survive!