Human males usually have one testicle that hangs a bit lower than the other, with an average difference in elevation of perhaps 1-2 centimeters. A simple experiment utilizing two eggs and a tube sock will demonstrate that this is in fact the typical configuration, as this arrangement would be at a lower energy state than an arrangement with the 2 testes at the exact same elevation.
But why is it that in a given male, it is always the same testicle that hangs lower? You couldn’t make the other testicle hang lower on its own if you tried.
And even more puzzling, why is it that, in humans, the left testicle tends to hang lower than the right? Why shouldn’t the odds for which testicle is lower be exactly 50/50??
I learned this in 6th grade and I’m glad I can answer it for you. It’s because as your testicles get bigger if they both were at the same height and one didn’t hang lower they would crush each other so during puberty one of your testicles drops lower than the other one.
WAG time, but with some background anyway. In the developing embryo the testes start out near the kidneys. The right kidney is further cranial (toward the head) than the right. Each teste ends up in the scrotum, however the left has a shorter distance to travel.
In support of this, when one of the two testes fail to reach the scrotum it is statistically more common that the right is the one which fails to descend. At least in dogs and cats.
A number of times, I have been told or read that in left-handed people, the right one typically hangs lower, but I have never been able to confirm this by research or experiment - I even started a thread about it way, way back, which (IIRC) was not entirely conclusive.
“Chang et al (1960) found that the right testis was the higher in 62.1% of 486 men, and the left testis higher in 27.4%, the two being equal in height in the remaining 10.5%. Antliff and Shampo (1959) found an essentially similar result in 386 men, the right testis being higher in 65.1% and the left higher in 21.9%. The two sets of authors differ in their findings as to the effect of handedness, Chang et al claiming that the relationship is reversed in left-handers, whilst Antliff and Shampo found no such reversal. There is also evidence that in the bull the right testis tends to be the higher of the two.”
The proper term is “dress”. A gentleman who dresses left is “lower” on the left, likewise contrariwise. In an earlier day, when tailoring was more precise to the body, this was an important thing for a gentleman of quality–or at least his tailor–to know about himself.