I live in Australian.
I'm trained in Sustainable Development and Permaculture though my current job is as a carer.
The world has the capacity to feed many more people and support all the species we currently have.
We make the mistake of assuming that there are shortages of resources and that our interaction with nature is a zero sum game. In reality free-market economics, innovation and exploration for new resources takes us past any limits. We must avoid extinction of species because that is the only irreplaceable resource.
We can do that by buying them as wild pets, private wilderness parks and by farming those species with useful products.
All other resources can be substituted for with other resources.
There are no limits to growth. The solar system has the resources to support 300 billion people in comfort and health.
Finding solutions that change the world is a challenge Which is why I use the term Applied Impossibilities on this site and my blog.
Today we take for granted things that were just science fiction a decade ago. Impossible wonders that only a few writers could dream of. The average poverty stricken house hold in Australia has wealth far greater than a Roman Governor or a Byzantine noble.