AndyH said:
At our current 1.096% growth rate, we DOUBLE the world's population in 63.59 years - that's more than 14 billion by 2075.
14 billion by 2075, its not going to happen. Because there is no exponential growth. You cannot take current rates and simply extrapolate them.
Take a look at this figure
http://www.google.com/publicdata/explore?ds=d5bncppjof8f9_&met_y=sp_pop_grow&tdim=true&dl=en&hl=en&q=world+population+growth+rate" onclick="window.open(this.href);return false;
The growth rate is subject to change and it is dropping.
Just 30 years ago if you had made the same prognosis for 2075, you would have come to 23.7 billion.
If you had done the "exponential" calculation in 1972, you would have come to 29.7 billion in 2075.
So which number is it going to be? 14 billion (2012), 18.6 billion (1992), 23.7 billion (1982) or 29.7 billion (1972)?
Taking the current growth rate trend it is going to be significantly less than 14 billion.
Needless to say, mankind is not going the way elks and bacteria go.
More wealth and education lead to less population growth. Ultimately resulting in stagnating or shrinking populations.
Problem solved, and in the process we have gotten richer and better educated.
The real problem is energy, since even at slowing population growth, we will use up the non-renewable fairly quickly,
but it can be solved, and fairly painless too.