By killing off animal species that normally would survive, and saving those that wouldn’t, are we interfering with evolution? What kind of impact would that have on anything? I mean, maybe it wasn’t nature’s way to have the dodo bird die out…Did we screw our futures by killing it? And animals that are slowly dying out from natural causes (I assume such cases exist) and we rush in to help the animal out, does that hinder or halt evolution also? When we eliminate “natural selection” from the scheme of things and replace it with “human selection”, what does that lead to?
Skwerl,
Evolution does not have a goal or anything, it just is. We humans are not screwing up “evolution”, we are just creating a more challenging environment for some species (the endagered ones) and an easier environment for others.
Besides, our actions may actually speed up evolution. By presenting a more challenging environment, we may be forcing a species to go through more drastic changes in order to survive, like becoming more appealing to celebrities.
It leads to domestication, for one thing (and the proper term is not ‘human selection,’ but ‘artificial selection’).
As to humans ‘hurting’ evolution? No. We do affect evolution, however. We impose numerous changes on the environment, and these, in turn, impose selective pressures on the organisms in those environments (as Zabes stated).
We are interfering with evolution in the sense that if we weren’t around, certain species may have evolved differently, or might not have gone extinct. But then, all species interact with other species, and there are cases of (non-human) species driving others to extinction.
Our biggest concern shouldn’t be that we are mucking with evolution, but with diversity.
You should bear in mind that over 99% of all species that have ever lived on Earth have gone extinct. Most of this happened before we humans arrived on the scene. Besides, it isn’t as though evolution has a goal or anything. As for wiping out various species… do you really think the ne-ne (I’m not sure how it’s spelled, it’s Hawaii’s state bird) would have lived so long if it weren’t on an island? These birds are incredibly stupid; for example, they lay their eggs anywhere, making no effort whatsoever to conceal them. They’re like that because there was no selective pressure on them for a very long time. If they go extinct because of what we do, is that any worse than them going extinct at the hands of some animal? Not really.
Humans have altered the evolutionary scene significantly, we haven’t “interfered” with it because we are another part of it. In fact, we’re now the most important part of it: over 99% of extinctions are now due to human activity, usually habitat destruction and introduction of exotic species (source: Primack, R. B. 1995. A Primer of Conservation Biology. Sinauer Associates Inc. p. 103).
I don’t agree that we’re ‘just helping evolution along’ or doing a good thing by wiping out species that are not good at survival. What we’re doing is meddling with ecosystems when we don’t understand how these systems work. Even worse, we depend on those systems to sustain life on Earth, including human life. It’s a little like tearing parts off your car while you’re driving, and hoping that you don’t accidentally rip off anything that effects engine or braking performance.
Do we want to eliminate species when we don’t understand the consequences? My answer would be no; excellent examples of valuable systems that have fallen apart as a result of human influence include coral reefs, wetlands, eelgrass beds, and various types of forests. And what species has artifical selection favored? Cockroaches, rats, and pigeons are the most dramatic examples. All animals with admirable resilience, but hardly the kind of thing we want to see as the primary inhabitants of the planet aside from ourselves.