Of course, species extinction is bad for, well, the specific species being extinct. But when adding humans to the picture, what impact does extinction have on the world?
So sorry, this belongs in GQ!
You never really know if it might have been useful to you for something later. Or if it filled a niche in the ecology which will now result in inconveniences or worse for humans.
That’s IMHO, anyway.
When talking about humanity’s detrimental effects on the environment, it’s really shorthand for being detrimental for humans. Earth itself has no problem exterminating species; 99% of all species that have ever existed on Earth are now extinct. Mass extinctions happen all the time, many far more catastrophic than anything humans have done. What saving the environment really means is preserving the environment so we can still live in it comfortably.
The food chain is delicate, remove one link and the whole thing falls apart. Say a certain species of plankton goes extinct. Big deal, we don’t eat that. A certain type of fish does, though, so if its food is gone, it dies. Then the fish that eat those fish no longer have any food, so they die. And those are the fish we like to eat, so now we’re out of luck. Let’s say the economy of Country A depended on exporting this fish. Their economy collapses, this has repercussions around the world.
Further, let’s say this type of plankton did a lot of photosynthesizing. Now that it’s gone, there’s a lot of carbon that’s not being sucked from the atmosphere and being deposited in the ocean. It builds up, and suddenly we have excess CO[sub]2[/sub] in the atmosphere, which increases temperatures, which makes a bunch of other species go extinct, wrecking ecosystems and possibly economies all over the planet.
It might help to anthropomorphize Earth and think that by polluting we’re “hurting” it, but what we’re really doing is making it less habitable for many species including us. We’re a part of the ecosystem too, and it’s up to us to preserve the environment for ourselves.
This isn’t really true. Mass extinctions happen periodically and have happened numerous times, but there haven’t been all that many big ones, depending on how one defines big, and they tend to be separated in time, which allows stuff to recover. Certainly “all the time” is overemphasis.
Also, the human-driven mass extinction shows signs of being one of the big ones, if we keep going like we’re going. That’ll mean that few will be far more catastrophic than anything humans have done.
Also, there’s a moral issue outside mere “utility to humans” and “future habitability for humans.” Asking why one should care about anything other than humans is sort of like asking why I should care about anyone outside my family – it’s simply not right, objectively, to kill everything except the small circle of things you’re personally interested in.
Every species that has existed represents a unique evolutionary solution to some set of challenges posed by its environmental history. Proteins have been tweaked; regulatory systems have been optimized; etc, etc. New problems and challenges arise all the time, and there’s no telling what we’re going to face in the future. It would be much easier to find solutions in species that are kicking around, having already dealt with whatever problem we have rather than trying to solve it from scratch. Not knowing what we’ll need in the future, it makes sense to try to save as much of what’s available as we can.
Case in point: PCR, one of the most important technological breakthroughs of the last century, was originally incredibly time consuming and expensive, because the DNA polymerase enzymes we had couldn’t withstand the high temperatures required for one of the steps. Solution: turn to bacteria (Thermophilus aquaticus) that live naturally in the nearly-boiling water of geothermal hotpots. They’ve already evolved polymerases that are stable and functional at high temperatures. Thanks to Taq polymerase, cheaply available from every lab supply company out there, PCR is now a staple technique of every biomedical laboratory in the world.