I suppose one could say the crux of the article is that a recent gene study sheds some light upon and increases our understanding as to why we and other mammals are the way we are, and such understanding may have future implications for medical problems and diseases related to testicles and reproduction. Yet much is still a mystery.
"There’s also the question of why testicles plummet in the first place. Given that they hold precious, life-giving contents, why carry them in vulnerable sacks? Scientists know that optimal sperm production requires temperatures lower than that of rest of the body, but they don’t understand why." Ah--air conditioning needed for production. And given the vulnerability to excruciating pain in this male area, women, with generally less physical prowess than males, have an achilles heal, as it were, where they can attack and temporarily disable an undesirable male, allowing them to move on and search further for a more suitable mate with more desirable genes.