By definition, Earth is not overpopulated by humans. But if we are talking about resources, then yes, humans are using up a lot of Earth's resources and by the next one or two decades we may be faced with crisis. But the market functions differently. If resource A starts diminishing, its price will increase and manufacturing firms will go for substitute resource B. Some examples of recent changes in the way we use resources are oil to petrol, or yields to fertilizers, among others. There are many, many lands and waters we have yet to mine or dive in and in the next two decades, we will have already discovered much more resources to cater for our needs.

there isn't enough water for people to drink. unless we can solve the sea water and make it drinkable for us, then yeah

Gurl yes!

Yes and nature is trying to make us exctinct thankfully

That's a very well known fact. (at leadt for LA)
http://news.nationalgeographic.com/n...orld-un-seven/ (answer 2)

Difficult to answer.

We are using our resources faster than we can restore them, so it is overpopulated in that way. The Earth can however hold even more people if we were able to change some things and properly use and create resources to be used