Currently that reason is us. We are destroying habitats faster than species can adapt.
The "why" is to preserve working ecosystems and biodiversity.
The "why" is to preserve working ecosystems and biodiversity.
> Ecosystems and biodiversity aren’t going anywhere.
If we keep up, they are. We can totally destroy the biosphere in ways that would make it, from our perspective, unrecoverable. Sure, it could recover in a few million years with other species, but that won't matter to us.
But we aren't, really. Long-term, we will be fully checked. And it will be ugly. In terms of humans, it's better that we check ourselves before nature does it because when nature course-corrects, it will probably look like a cataclysm to us.
But you can also interpret "currently" on a geological time scale.
https://earthsky.org/earth/early-humans-wiped-out-big-animal...