Undescended testicles (Cryptorchidism) appear to be of complex origin . . . one of those cases where there are genetic and environmental components, and therefore difficult to figure out. You can consider genetics, exposures to environmental estrogens and anti-androgens and the relations among risk factors. You will not be bored trying to figure this one out. Added to this mix is a previously unconsidered variable: Hybrid Cars.
I teach a course called "Introduction to Research" which is somewhat like boot camp for aspiring academics. I would now only encourage people to go into academia if they are so driven by love or fascination for a subject that they are willing to sacrifice a signifant amount material comfort in its pursuit. I described my 16 year old minivan as dented and rusty, with an interior re-upholstered piece-meal with green fluorescent duct-tape. The starstruck response: a breathless and drawn out "cool . . . " I went on to describe my leaky roof and deceased dishwasher, and received this: "Dr. K, I will come to your house and fix your dishwasher" followed by "and I will drape my body over the hole in your roof next time it rains" from yet another. Undergraduates can be absolutely amazing.
So, to the hybrid part of the cryptorchidism story. The minivan leaks oil, gets not-so-good mileage and I drive about 120 miles a day to commute to the University. This is horrible for the environment, and costs about 1/7th of my income in gasonline alone. It suddenly struck me, during a quiet conversation with a good friend, and sometimes nemesis, that I could get a used Prius and maybe come out ahead financially on the reduction in gas expenditures. "Oh No! I'm Emasculating!" (that wasn't exactly how it was phrased, but you get the point: he has just become cryptorchidic). I only struck up a conversation with him in the first place because he looked like a hippie and a good environmentalist. Just another reminder not to speak to strangers even if they look "nice".
So what's the deal with hybrids and environmentalism that threatens the masculinity of men in Texas? A simple question, that could be answered with a simple "beats the hell out of me" until I started considering bumper stickers:
This is a question that should be posed to an historian, psychologist and/or poli sci person.
Foresta, C., Zuccarello, D., Garolla, A., & Ferlin, A. (2008). Role of Hormones, Genes, and Environment in Human Cryptorchidism Endocrine Reviews, 29 (5), 560-580 DOI: 10.1210/er.2007-0042