motivation for evolution

Summary: "animals have no self-interest in leaving descendants, evolution works, but not for the happiness of its members"

Survival of the fittest, right? A species continues if it leaves descendants, and in order to do that, the animals have to not be killed off, right?
That's obvious, that makes sense. The species we see now are the ones that left offspring and tend to do that.
But why do animals (human in particular) have an interest in reproduction as they live? I mean, we die, and then what? We might only care to have children if we want a nice nursing home.
You might want to leave a legacy, make a difference in the world, raise the next generation, continue the domination of makind over other species, but why would you want any of that? You'll die eventually, and then you won't care will you?

I would be talking to an evolutionary scientist (I'll admit I'm being a little harsh and naive, but I love this idea). I would say "What do you care if our species survives? Why do we reproduce? What motivation do we have? Why should we/you obey our/your evolutionary drive? You only have this drive because you wouldn't be here without it. Why pass it on? What do you care if you reproduce?"
Then I had this thought (which is untrue but funny): what if, once a species becomes advanced enough, it realizes that it doesn't care what happens after its generation is gone, so it doesn't bother to reproduce, leaving the next intelligent species to muddle its way to that conclusion on its own? is this why it's taken the world billions of years to produce intelligent life?

Note that we humans are nearly taking this idea to heart. We advocate not overpopulating the earth, many couples have abortions because they don't want to bother with children. Only-child families are quite common nowadays (well, I hope not).


Oh by the way, guess what sort of people are keeping the population up? Big families, right? Who do these people tend to be? Inner city poor a lot of the time, crazy homeschool families, right wing farms, mormons, rednecks, etc. Hmm... No liberals mentioned anywhere. Sort of a rag-tag assortment of loonies. (I include myself)
Let me see, survival of the fittest...