The following are all higher up on the evolutionary food chain than Wal-Mart employees.
Fire ants.
Monkeys who fling their crap at each other.
Single-celled amoebas.
Spiders.
Those funny baboons with the big blue asses.
Algae.
Barnacles.
Foot fungus.
Dryer lint.
The dump I just took.
Snot.
That green junk you have in your eye when you wake up.
Fleas.
Bacteria.
Tequila worms.
Seaweed.
My favorite pet rock.
Jack Black (but not by much).
Ben Stiller (again, not by much).
Good Charlotte...on second thought, no, Good Charlotte is even lower than Wal-mart employees.