1. It can remove semen.
A penis releases semen, and according to evolutionary scientists it can also remove or displace the semen of male competitors to assume paternity. It's able to do this thanks to its shape. During intercourse, when a guy is thrusting in and out, the ridge at the base of the penis head rakes away and does the job.
2. It can still function/perform without the head.
Parts of the penis or the whole thing can be removed in the case of penis cancer, for instance. Good news: Guys with headless penises can still urinate, have sex, and ejaculate.
3. It "smiles."
The penis is flexible, so much so that it curves like a boomerang during sex in the missionary position. So sure, you can think of it smiling.
4. It can tell you about his brain.
According to this research in the journal Human Reproduction, a flaccid penis that hangs to the left most likely means that the guy is left-brain dominant, which suggests his being good with numbers and analytical thinking. On the other hand, if it hangs to the right, the guy is probably right-brain dominant and therefore more able to read expressions and be creative.
5. It can tell you about his health.
Physical health and penis health go together. A guy who's having a hard time sustaining an erection can suggest that he's got sleep disorders, he's drinking or smoking way too much, he has diabetes, or he's putting on some weight. (Heavy guys usually have lower testosterone levels, which can contribute to erectile dysfunction.)
Also, if you think your guy's penis has gotten shorter, it could be because he's smoking a lot. Erections are all about good blood flow, and smoking calcifies blood vessels hence hampering erectile circulation. The result? A penis that's a centimeter short.
6. It can tell you about his orgasm.
In this study, researchers found that the force with which a guy ejaculates is associated with how satisfying his orgasm is. The more satisfied he is, the farther his semen goes. If it squirted beyond his navel, you know his orgasm was out of this world. (This applies only when he's lying on his back.) (This is perfect for when you want to know how much he enjoyed the hand or blow job.)
7. It'll shrink with age.
A number of things happen to the penis as the years go by. One of them is shrinking in length and thickness. It could be caused by impaired blood flow in two ways: because fatty substances have clogged the arteries in the penis, or because erection chambers (which are supposed to be filled with blood) have been surrounded with inelastic collagen (or scar tissue). They give smaller erections, and the penis becomes half an inch shorter when the guy hits his 60s or 70s.
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