I'm not sure it's the population that's the problem -- there are a number of factors. If we globally stopped eating meat then a large portion of the land used

I'm not sure it's the population that's the problem -- there are a number of factors. If we globally stopped eating meat then a large portion of the land used for agriculture to produce livestock feed would not be needed and could return to forest. And we'd all live and be healthier for it (yay less heart disease and cancer). The amount of land used to grow food to feed cows is a large portion of the total agriculture output. Organic farming seems like it could be sustainable even if portions of our stocks are taken by insects. It'd be manageable without pesticides. And if we invest more in genetically modified vegetables we could grow them to be resistant to pests without filling the environment with pesticides. We humans used to be pretty good at permaculture: https://en.wikipedia.org/wiki/Permaculture https://en.wikipedia.org/wiki/Permaculture