Think of birds seeking nesting places. The best spots are taken first - they are staked out first and defended rigorously. Then less optimal spots are then occupied as more birds arrive on the scene. Finally, when are too many birds and too few trees, what is left for the late arrivals are spots nearer to the ground and more exposed to predators, or spots on flimsier branches that are more exposed to the elements and to the wind.

The birds with the least desirable nesting spots - especially if they are low on the dominance order and/or dancing or singing ability as well - are the least desirable males, chosen last by the least capable females. They will put effort in, but their eggs and young are the least likely to make it.

We are in the last stages now. The vast majority of what is valuable and income-generating is already owned by somebody else. Everyone else is just competing with their labor - and the labor supply continues to grow even as labor demand decreases.

Marginalized humans in Third World countries live in garbage-strewn, pollulted, crowded places working for 25 cents an hour. Marginalized humans in Second World countries work in factories or offices for $2 to $5 per hour, while renting tiny closet basement apartments. Marginalized humans in post-Industrial First World countries work part-time retail or service/hospitality jobs or can't find work at all, live in urban ghettos, dying coal towns, or rent a room or couch-surf in busy metropolises. They may be highly educated, but they have a hard time finding jobs or ekking enough of a living to save for any kind of meaningful future as their parents had.

With a human population in severe overshoot, on a finite planet with depleting resources, we have crowded out almost all other life - causing more than half of all other wildlife out there to have disappeared since just the 1970s alone. Now we are crowing each other out.