• James E Aarons DVM

When Testicles Go Awry


Did you ever wonder why god kept the testicles outside your body, hanging in a sac-like thing called a scrotum?

If you’ve ever been hit in balls, you’ve probably wondered: Why are these things on the outside? Obviously that outside hanging position makes them vulnerable to injuries when hit accidentally or kicked by someone deliberately.

Why would the hand of evolution allow these treasures to dangle outside the body, where wind, rain, and all kinds of evil might visit the twins?

It's because the twins need to be cooler than the rest of their support system!

Testicles are responsible for producing sperm. Current thinking supposes human body temperature is much higher than what is required for sperm production and sperm survival. Therefore, if testicles were inside the male’s body he could be impotent because of defective sperm production.

Since the testicles hang outside the male’s body it’s not affected by the body heat directly because the air circulating around the scrotum keeps the testicles cooler, in comparison to the temperature of the body. A man’s swimmers don’t have a long lifespan once they’re active, so it’s possible that, in ideal conditions, sperm doesn’t fully wake up until they're released into the warmth of a woman’s vagina. It happens to me too, that extra focus when I realize I'm near a warm vagina.

Another interesting phenomenon is the testicles moving closer or away from body due to variation of environmental temperature. During cold winters males testicles are drawn near to the body to protect sperms from the harsh cold.

This same logic explains why tighty white underwear for men are discouraged. Tight underwear brings the testicles close to the body which raises the temperature inside the scrotum, creating an environment testicles might find unsuitable for spermatogenesis.

Sorry guys, but men have some of the smallest testicles in the animal kingdom

Compared to many animals, human males don’t have very big testicles. This is a very popular topic for research and many scientists believe it’s related to our relative lack of mate competition. It has been shown across all kinds of animals, from chimps to insects, that balls tend to be bigger when females are more likely to have more than one mate. The most popular hypotheses is that larger testicles release more sperm. Maybe pants were a bad idea... I mean, if us bigger fellas didn't cover them up, life could be a lot easier in regards to picking up chicks.

Good news! They get bigger during sex. Bring a tape measure to bed!

Just as blood goes to the penis when a man is aroused, it also travels to his balls. This can cause the testicles to increase in size by 50 percent or more! However, if a man’s balls are changing in size — whether getting bigger or smaller — at other times, he should talk with his doctor or veterinarian about this difference as soon as possible.

Cryptorchidism, a congenital defect when a testicle doesn't descend into the scrotum

While male humans, dogs, cats, etc are developing inside mama's womb, our testes originate embryonically just below the kidneys, the same place the lady's ovaries appear. The difference is that the ovaries stay in this location while the man's balls-to-be need to make their first manly trek. They need to head down under for the coolness of the environment. Cryptorchidism happens when this scrotal journey is interrupted.

And the testicle won't develop correctly when it gets caught; it is smaller, and different, not quite right. It is best recommended that the undescended testicle be removed in dogs and cats.

Last Vet Story Next Vet Story

Pinning Houdini's Leg Bladder Stone

Normal and Cryptorchid Testicles