How the Human Race Went Extinct 200,000 Years Ago.

About 200,040 years ago, humans came to the conclusion that it was heartless, irresponsible, and politically incorrect to tolerate the following social evils:
1) Allowing the deformed ("differently abled"), sickly ("chemically, allergenic... sensitive") and stupid ("mentally challenged"), to die at birth or shortly thereafter.
2) Allowing those unable or unwilling (by reason of their attitude, health, or age) to hunt or gather, to die.

They decided that all human life was valuable, regardless of circumstances. They decided that all possible resources should be devoted to sustaining the lives of those that had theretofore been allowed to naturally die. This led to increasing time being spent on caring for the increasing population of those unable to care for themselves. Increasing resources were spent on those unable to care for themselves.

Yet, those unable or unwilling to care for themselves also bred, in addition to the able and willing people, increasing the numbers of those unable or unwilling to care for themselves.

So, fewer people were available to gather (increasing numbers having become engaged in "care"), and what was gathered had to be divided amongst more people. Fewer people were available to hunt (increasing numbers having become engaged in "care"), and what was killed in the hunt had to be divided amongst more people.

The people began to starve, and yet they continued breeding a larger but even more unviable population. After all, "growth is good", "compassion is good", "oh, the children, sob, sniffle", "everyone deserves food, fur, and pharmaceuticals". After two generations (forty years), the human race then went extinct 200,000 years ago.