> a world with just farms and cities and the animals that can survive within is not going to bode well for us or any other species
In what way?
The main threat is disease if we shift to being large aggregations of essentially the same animals. We've run in to this problem before, with bananas as a particular case. However, we already know the solution to that. The answer is that you preserve several cultivars of the species, and intermingle them. We already see this kind of behavior with pets, gardens, zoos, etc. I fail to see why you think we're likely to end up with anything but more of the same kinds of pruning-but-not-completely-destroying-families behavior.
I'm also failing to see why you think we need thousands of kinds of lizards that are all basically the same, rather than a few hundred, and why such a bottle neck is either unnatural (hint: we've hit smaller choke points before) or why it would be particularly dangerous.
In what way?
The main threat is disease if we shift to being large aggregations of essentially the same animals. We've run in to this problem before, with bananas as a particular case. However, we already know the solution to that. The answer is that you preserve several cultivars of the species, and intermingle them. We already see this kind of behavior with pets, gardens, zoos, etc. I fail to see why you think we're likely to end up with anything but more of the same kinds of pruning-but-not-completely-destroying-families behavior.
I'm also failing to see why you think we need thousands of kinds of lizards that are all basically the same, rather than a few hundred, and why such a bottle neck is either unnatural (hint: we've hit smaller choke points before) or why it would be particularly dangerous.
Ed: A key word.