Overpopulation is going to start to become a problem. It took us about 2000 years to be the population we are today, but there saying that our population should double in 50 years.
Another problem with overpopulation is that we don't have enough resources to feed 7.1 billion people. Another question is how will we be able to feed 9 billion people. How can we grow so much food right now and still not be able to end world hunger. Another thing to know is what are we going to do when just our 4% of our growing space is taken away. By civilizations that need to make more room for there family's. And another thing is sooner or later how would we be able to get enough oxygen to every single living being. Because sooner or later there going to have to cut down more trees to make more houses and whats going to give us our oxygen that we need.
As of today it shows there is 7.12 billion people. It showed that we reached 7 billion on March 12,2012. The world population has experienced continuous growth since the end of the Great Famine and the Black Death in 1350.
Overpopulation: A Growing Problem (Infographic)