10 / There is two different kinds of penis

Men can have two different kinds of penises, the first kind is big even at a relaxed form and expands just a little with erection (this kind of penis is named exhibitionist). The second kind is small at the beginning but can duplicate or triplicate its size and thickness (a growing penis) with erection. 79%  of men enjoy the second kind and 21% have the exhibitionist penis.

9 / Orgasm lasts only about 6 seconds

The average male orgasm lasts 6 seconds. Women get 23 seconds. The female orgasm triplicate the mans, which means if women were really interested in equality, they'd make sure we have four orgasms for every one of theirs ;)

8 / Penis’s sexual intercourse lasts minutes only 2:50 minutes

One scientific investigation in Germany concluded that a penis sexual intercourse lasts only 2:50 minutes. No more!

7 / You can break your penis

Yes, and it’s not a joke or a lie, you can indeed fracture your penis and the leading cause of penis fractures is a savage or vigorous masturbation. So be careful ;) 

6 / Circumcision

Circumcision is a simple medical operation that lasts a few minutes. Circumcision is the removal of the foreskin, which is the skin that covers the tip of the penis. It is a very cumon operation due to religious or cultural tradition.

5 / The size does matters

A scientific investigation performed by New York University shows that size does matter: The longer your penis, the better "semen displacement" you'll achieve when having sex with a woman flush with competing sperm. That's according to researchers at the State University of New York, who used artificial phalluses (ahem) to test the "scooping" mechanism of the penis's coronal ridge. Next up: curing cancer.

4 / The animal with the biggest penis

In absolute terms the animal with the biggest penis is the whale with 2,4 meters. Unfortunately this amazing animal was never recorded pairing because it is specially complicated to record this animals in sexual activities for that reason the size in erection is unknown.
The animal with the biggest penis in proportion is the barnacle whose penis is twice his body’s size.

3 / the foreskin can produce 23,000 M2 of Skin 

Doctors can now grow skin for burn victims using the foreskins of circumcised infants. One foreskin can produce 23,000 square meters, which would be enough to tarp every Major League infield with human flesh.

2 / handsome man, stronger sperm

Better-looking men may have stronger sperm. Spanish researchers showed women photos of guys who had good, average, and lousy sperm—and told them to pick the handsomest men. The women chose the best sperm producers most often.

1 / Smoking shortens the penis

Smoking can shorten your penis by as much as a centimeter. Erections are all about good bloodflow, and lighting up calcifies blood vessels, stifling erectile circulation. So even if you don't care all that much about your lungs or dying young, spare the li'l guy.