[Physicist]

I only have a problem when people think we're going to drive them all into extinction without drastic new action.

Extinction per se isn't the issue. Depletion to the point of uselessness is, in economic terms, the same thing. We are certainly headed there if nothing is done.

Look at the whaling industry. It used to be big business, and while the whales aren't exactly extinct, the industry itself is gone. (Yeah, I know, government drove the last tiny remnant of it out of existence, but what really killed it was lack of whales.) We could use that industry back again. People need jobs, and I myself wouldn't mind tucking into a nice, big whaleburger. But to do that, it takes whales.

[LS]

Your theory is right, but the example of whaling is wrong. I've actually written about this and looked at the studies. The whaling industry CHANGED when Rockefeller refined kerosene, making whale oil (forget food---it didn't comprise that much of the market) relatively more expensive. The transformation was pretty abrupt. Whaling was virtually dead as a major American industry by the 1880s.