Whether or not the forecasting models are accurate or not..(I am NOT conversant in those maths), the issue of the effect of even the current level of population is very much with us.

I was watching a program last night where several widlife biologists were commenting on species diversity and extinction patterns, particularly in the African savannah.They all were just short of panicing at the continued loss of both plant & animal species, largely as a result of human encroachment and pressure.

Lots of work is being done on these matters, but once a species is stressed so far, recovery is difficult....if we DO reach 7-9 billion, and Brazil & Borneo continue to be chopped up & burned off...etc., the year 2100 looks pretty bleak to me.