>the end of human civilization
This made me think about the extinction of man, how it might occur. I think for civilization as we know it to end humans must go with it. It seems most species on Earth go extinct from either:
a. Hunted by predators/humans b. Ecosystem collapse (no plants so herbivores then carnivores die) c. Apocalypse like the asteroid that killed the dinosaurs and d. Habitat loss

I don't think humans will be hunted to death or out-competed by another species for food since we can just shoot the animals that try. Aliens could but that's more for scenario C.
Ecosystem collapse seems kinda plausible since ocean trash and oil spills etc. might do us in, like WALL-E but without a ship to run off into space with. However, this would need to be on a global scale since humanity occupies the whole globe (I know the term "human" is generous in some cases, but for simplicity's sake let's just call them human) and if all the food magically disappears from one country or even continent the rest of the world would launch a big humanitarian mission to feed people, such as in Africa.
An apocalypse seems unlikely but would definitely be the most exciting, if man were to go extinct at least make it fun! Just watch a movie for an idea: tsunamis, aliens, zombies, nuclear war, etc.
Finally there is habitat loss. Unless Earth becomes uninhabitable before being consumed by the sun this one is basically impossible since we can just build houses with air conditioning, heating, air filters or whatever would be needed to cope with a hostile environment.

All of this is to say that humans probably won't die out in the same way as animals since we can adapt to almost any environment and organize on a global scale to counter catastrophes and famines. Humanity's extinction will probably be caused by ourselves in a unique way. What that is can't really be predicted but if I had to guess it would be a very slow and boring decline as technology regresses, war kills even more people, charity and humanitarian efforts slow then cease, towns and cities become empty as the infrastructure cannot be maintained. Finally the last child of man is born and, some decades later, dies and takes humanity with it. This was mostly inspired by Threads and Girls Last Tour, they both left a strong impression on me.