GC I think that you will find that the onus of proof is on DA to back up what he saysand not on the sceptics. Of course he is entitled to his opinion, and his opinion is as good as anyone elses but that is all it is without evidence.
You said
"In ecology, this over population issue is best compared to the 'Equilibrium Model'. Immigration of new species establishes an equilibrium with the extinction rate of other species. So in this case, if the Human race continues to grow, then it must do so at the expense of other species.
In this respect I think DA is imminantly qualified to make the statements he has made. We are after all an organsim that shares a finite set of resources with many other organsims. The question is where is the human race relative to this equilibrium? If we are beyond the equilibrium, which I suspect we are, are we proposing suitable artificial stimulus to achieve a sustainable equilibrium bearing in mind future population growth."
And what exactly is the problem with our survival being at the expense of other species? Isn't this Darwinism at work? Survival of the fittest and the fittest survive. DA is a Darwinist so what is his problem? Is this too crass a view?
