link: Are we in the middle of a mass extinction?

Are we in the middle of a mass extinction?: "The definition [of mass extinction] I like is where you have numerous phylogenetically distant organisms involved in losses at the same time. For example, 65 million years ago there was a mass extinction. Dinosaurs were lost, but what made it a mass extinction was that all kinds of other species went down at the same time - all large marine reptiles and primitive types of birds, as well as many groups of plankton and other one-celled creatures. It was a large scale extinction that affected apparently all ecologies on the planet, from moderately deep marine to high altitude terrestrial ones. These were dramatic losses. By contrast, the End Pleistocene [about 12,000 years ago] doesn't stack up as a mass extinction. There were losses of large mammals [like woolly mammoths and mastodons], and some small. There were bird losses in the scavenger/raptor category. But then the loss picture drops off to nothing. There's no evidence for large extinctions among reptiles or fishes. Nor for plants."

It's nice that an expert in the field doesn't think we're about to suffer massive collapse, but I just keep thinking, 'what if it's as bad as they say?' and 'what if this is what it's like at the beginning?'. I mean, we have the tools now to notice the dying-off, but in the past, it would have just been, I don't know, that bird never came back one spring, and that kind of frog isn't here in the pond anymore, and our grandkids don't know what that particular tasty animal even looks like, and then one day, there's a creature walking around in a landscape devoid of anyone like him, with no ecology to speak of, and when he dies, 75% or 90% of the world has become fossils. Along the way, probably no one thought about it, or if they did, they didn't think everything would be gone. If there was even anyone to think about it.

We're just in this position where we have these big brains that make us speculate and allow us to speed up the process and notice when it happens... and deny that it might be. And do something about it.

Say this is the start of one of these massive events. Maybe everything will just collapse in the next decade and people alive now will notice that things have changed, but maybe it will take three thousand years, which is very VERY slow for people, but hardly anything for stones and the fossil record. Would we even understand in three thousand years that all the things that sound like really old myths were once real animals and that the ecosystems were once rich and diverse, or were so in very different ways than they are then? I mean, if this is the middle, and not the beginning, we only started to notice recently when big things like buffalo and dodos started going missing. How many more things died off that we didn't notice at all?

Maybe we should act like there's something we can do about it and try to avoid the big hit: maybe it's going to happen anyway, but maybe we can preserve genetic lines and captive-breed and genetically engineer, and build arc ships and colonize other worlds and spread out beyond the system of this one planet and maybe we can save it: expand the idea of a local population from a single woodland to a whole planet, and maybe things can keep living and diversifying elsewhere and survive.

Even then, though, things will change. Nothing stays the same. If we choose the strongest lines and preserve them, we've just sped up evolution in whatever direction we define as strongest, and maybe those wolves on other planets will be gigantic; or maybe they'll be small, domestic puppies that only look like wolves. Maybe the buffalo will be affected by new ecosystems and become something not at all like a buffalo. Maybe the panthers will go feral in the domes on the moon and get smaller, longer-legged, arboreal in the light Gs. Who knows? We would only have saved this moment in their evolution; in the future, we can't guarantee that anything we save will still be that thing, even if we only stay on this one planet.

Conservation seems to have this idea that we can stop time, and that's not the point. The point is to not kill everything so the ecosystem can stay solid; the individual animals are less important than the whole, because while wolves and buffalo and panthers are impressive, if they were all entirely gone, other things would step up to fill the roles of hunters and herbivores, and the ecosystem would eventually balance out again and be fine.