g day Ben, Andrew Andy et al,
all good points

and no, no studies just my observation.
i am heartened by business' responses like the example Ben gives BUT big business via profit at any cost and consumers buying on price alone have created the bulk of the problems the 1st world's wasteful and unhealthy consumption is compounding.
and yes 3rd world kids are often born and left to survive as their skills permit in the hope that at least one will be able to support elderly parents. raising their economic standard is the one way i have observed that actually breaks that cycle. its an unknown if we can do that raising and maintain the habitability of Earth until the global population goes into decline. again China seems to be be doing far more radical anti pollution changes than the West. it can be argued they need to! but the point is they are.
i do observe that the generation raised in the 1st world do breed far far less. dunno if its 'cos they can't afford the kids. it may be a choice to spent on extra comforts AND they don't have to play the numbers game for their doter age. the pension and just one or two kids is fine. this then compounds on through the generations.
a key for it all to work tho is far far smarter consumption by all worlds, espec the 1st.
regards, L