Why does your left testicle hang lower?
While 65 percent of women have a left breast that is larger than the right, the same percentage of men have a left testis that hangs lower in the scrotum than the right. The left testicle also tends to be 7-10 percent smaller.
Why?
It’s a question that won an IgNobel prize for Chris McManus. Although scrotal asymmetry is faithfully reproduced in Greek sculpture, the British psychologist observed, the Greeks weren’t exactly anatomically correct. Greek sculptors faithfully made the left ball lower, but they mistakenly made it larger. Absurdly, they thought the testicles acted like weights to keep open the ducts when semen was released. The left one was erroneously believed to be heavier.
Hundreds of years have passed and we still don’t exactly why the testes aren’t side-by-side and symmetrical, but there are a few theories that touch on the mystery:
Temperature regulation. A French study found that the left and right testicles have different modes of thermal regulation. The left runs hotter than the right. They hang at different levels because they have separate arteries and veins that differ from each other in length, angle, and source. Sperm are temperature-sensitive, so having redundant semi-independent temperature regulation mechanisms may be beneficial. Researchers also speculate that twin testes, if snugly pressed against each other, would run too hot and thereby impair sperm production. More exposed surface area = cooler. Hanging at slightly different heights prevents them from crushing and overheating each other.
Handedness. Some studies have found that the left testicle hangs lower in right-handed men and the right testicle hangs lower in left-handed men. Handedness is linked to cerebral asymmetry, and there is some suggestion that testicle size and position are, too. Intriguingly, scientists are investigating whether cognitive performance can be predicted by the testes. According to a Canadian study, men with a larger right testicle performed better on spatial tasks than men with a larger left testicle. (Again, on most men, the left is smaller.)
Poor thing. The littler, lighter, lower-hanging left testicle has such a bad reputation that, according to the Urban Dictionary, it’s now slang for slacker.
I always thought that, since testes are very sensitive, one hangs lower than the other so they don’t “bang” into each other while the man walks or runs.
Why there is a preference for the left might have to do with your two hypotheses.
Nice post, but just a word of warning. When I was a teenager (quite a few years ago) I too noticed the asymmetry of my testicles and I too was told this was normal – as you correctly outlined. So I thought nothing more of the size differences in my testicles. But how much asymmetry in size is relative. It ended up my asymmetry in testicle size was not natural – one was cancerous. The degree of asymmetry grew and I should have been more aware. It was not until very late did I finally go see a doctor and found that I had advanced cancer.
So my word of warning is yes testicle size asymmetry is normal – but if pronounced maybe you want to have things checked out by your physician. Catching cancer early is obviously better than latter.
Thanks for your interesting post – even if it brings back bad memories
[...] little piece on testicular asymmetry. Apparently, it’s normal for one ball to be smaller and hang lower [...]
My right one hangs lower, am I some kind of freak?
Benjamin,
Is your heart oriented more to the right-hand side of your chest cavity than to the left? In some males other organs may have the same bilateral asymmetry as the testicles. It is an interesting phenomenon and documented to the point that physicians use it as a diagnostic primer. I’ve seen the question asked on university medical school exams.
One hangs lower so they don’t smash against each other while walking. Otherwise men would be bo-legged just to keep from the pain. But all this goes into the fact that all of us are different on each side of our bodies.
Try this, take a picture and cover up the left side of the face and then switch sides. You will see to different faces.
just know bout it… never think bout tat before…
If they hung evenly when they were hit together they would crush each other. Since one is lower, one will override the other if they are mashed together.
I have always thought that they hang lower due to damage. like if they get hit the right one will still work and the left will get hit really hard but won’t work. (you’ll have one working ball rather than none.)
I always figured it was so my package could fit comfortably down the leg of my 501 jeans.
lol now i only have one testicle that hangs lowest!
Are you going to do a post on why the Vagina is shaped like a wallet?
Now that’s a life-changing information, uh!
Just think of it, if they were the same identical size and weight, one testis would crush the other, or if they hung too low, they my simply twist together. No Nobel prize for that, just common sense.
aaah, the wonders of the http://www.. now i know why testicles are asymetrical. this is exactly the kind of thing i wanna learn at 3am on a sunday night
m. @ http://umstrum.wordpress.com
lol i never really questioned that ever..!
Whilst naked, if you sit, primly, with your knees together, you will see one testicle ride up and over the other. If your testicles hung at the same length then there would be a calamitous crush like when two people try to go through the same door at the same.
My wife assured me that I am a lower-lefty! LOL
Luckily, Someone is doing this research. I thought my tax dollars might be being wasted.
Tyler Dockery
http://www.dockerydesign.com
http://twitter.com/tyler_dockery
—————
Nice new information.
It’s not like they’re immobile, I’m guessing they would still “fall into place” regardless of what length they hang, there’s plenty of room. I’m liking the reproductive reason. It’s a pretty advanced thermostat, after all
I think it’s the handedness theory. In women since more are right handed, their right breast would be more muscular, therefore smaller, since the breast is mostly fat. That dominant side reason should also lie true for testies, since men have dominant legs too.
Of course I’ll have to check that theory later… as a left-handed athlete.
I suspect that, they have to be oriented in some manner or another. And, as your male body develops they crowd each other together and one falls into place below the other, usually the left one. I guess…
I Really Love Reading Your Blog. Excellent. Keep up the great work!
Great post. There are 1,000 guys at home right now.. with their pants around their ankles checking to see which one hangs lower.
i have been conducting my own private survey about this for years, just as a amussing way to start a conversation. It surprised me to see this. I had always theoriesd that the way the testes hung was attached to the handedness because in the womb the side develops first is stronger then the second side (i vaugely remember i was taught that is why some people are right or left handed) so that relates to the testes when; if you are right handed you right side will be stronger = tighter so the musels of your right testie will hold that one closer, and your muscles on the left side weaker = droopier it was reversed for left handed people. that was my conclusion of my privete study any one know any thing about ambedexterious people?
But what does it mean when one of them starts to larger than the other two?
From my understanding and education, I have been taught that this is actually a result of vascular differences. The testicular arteries and veins have different origins and drainage points. (Search for testicular vein images) As a result of these variances, the left testicular vein actually drains into a smaller (renal) vein where the right drains into a larger (inferior vena cava) vein. This will cause the pressure in the left vein to be greater as there is more resistance. Greater pressure and more blood cause the testicle to hang lower as a result. The scrotum also has the ability to contract/relax for temperature regulation which equally plays an important role in this height difference. As for a third reason, the shape of two spheres can be in closest proximity when they are offset just a little allowing the testes to occupy less space than if they were side by side. I hope this enlightens someone, and this is a great question that I am glad to finally have an answer to.
I dunno. With me it’s my third testicle that seems to be the largest.
…and don’t EVEN get me started on ears…
Thanks for the info, it took a lot of balls to write this.
nice post, interesting
now i don’t have to wonder why
trackback on http://uzisero.blogspot.com/
Plus, it’s more aesthetically pleasing.
The larger ball hangs lower and the slightly smaller ball rests above the bigger one. It forms a graceful, linear line.
Slacker…lol…. I never heard that one
It’s all to do with the angle at which the earth spins.
[...] HERE to read Jena’s article and see the answers [...]
As far as the speculation goes, what people seem to gloss over is that according to the first part of the article, approximately 35% of men have testicles that are on equal levels. There may be some self reporting bias here, so taking an even more conservative number, we can say that at least 25% have no asymmetry in testicular levels. An interesting study then would be to see if this is related to possible ambidexterity. Also, it would be interesting to see if there’s a correlation with sperm count and testicular dominance. One other thing to keep in mind as far as the speculation, if 25% of the population was the outlier, than they wouldn’t be as likely to reproduce and that trait would not have remained in human populations. Perhaps then, testicular asymmetry isn’t as correlative with dominance as this article maintains. As far as the temperature regulation hypothesis, this must also be tested among the left lower, right lower, and symmetric groups.
the good thing about testicular cancer is you can only get it twice.
In my case, the left one does hang lower. But the right one is significantly smaller. All of which means nothing.
By the way, I am right handed.
i am a right-handed man, and my right testicle hangs lower and is smaller. and according to the above text. that is not possible. any comments or concerns?
how can you tell if one of your testicles is twisted becuase mine sometimes get flipped and stuff when i walk and i think they are back to normal but dont know