Yes! We are natives of the land where we were born and raised.
It makes little sense that testosterone levels independently started decreasing. Occam's Razor says that civilization and technology made it possible for weaker humans to survive thus the decrease in testosterone related features in humans.
"The Mets were great in 'sixty eight, The Cards were fine in 'sixty nine, But the Cubs will be heavenly in nineteen and seventy." -- Ernie Banks