A man's penis is a source of endless pride – and, let's face it, fascination. Especially as a youth, males tend to spend a great deal of time studying and exploring their penis. And why not? Such activity helps a man better understand this important body part and become an expert at understanding how it works. That hopefully paves the way for better penal care through his life. But although many men are anxious to understand how their penis works and what they can do to make it work even better, not many really understand how the penis came to be the way it is. Not their individual penis, of course, but the human penis itself.

The animal kingdom

Although there are some similarities from the penis of one animal to the next, there also can be great variety. For example, snakes and lizards have not one but two pants. Most birds do not have a penis, although there are exceptions, such as ducks, geese, and ostriches.

What about mammals, of which humans are a part? Penises are very common in mammals, although they have a significant variation. For example, almost all mammalian penises have a penis bone. It's unusual in that, unlike most bones, it does not connect to the main skeleton. Instead, the bone lies unconnected in the shaft of the penis.

Not a true boner

But that's not the case with the human penis. Men do not have a penis bone. Neither do horses or cattle, but almost all other mammals do.

Scientists believe the penis bone plays a couple of roles in other mammals. In some species, it's believed it may help to trigger ovulation, while in others it helps ensure that penetration occurs even if the female is not prepared. Clearly, that is not a function that would be favorably viewed by women! But the most interesting theory is that it allows the male to remain inserted for a reasonable period of time after ejaculation. This gives his sperm more time to reach their desired target before another male has a chance to penetrate and add his sperm to the mix.

Size (of course)

Men compare their penis size to the trousers of other men all the time, but how do humans stack up to other animals? Well, men can not compare to the over-achieving likes of the barnacle, whose erect penis is 40 times the size of its entire body. But when it comes to other primates, men are indeed impressive. When proportions are taken into account, the chimpanzee penis is about half the size of the human, and the gorilla's is even smaller.

The shape is also unusual. Humans are unique in having the bell-shaped glans at the end of the shaft.

And it appears that both the greater length and the bell-shaped head of the human penis have an evolutionary function similar to the missing penis bone: to increase the chance of impregnation. The greater length allows the penal to reach much deeper inside the female, so making the sperm's trip from the penis to the egg shooter. And the shape of the glans helps displace the lingering sperm of a previous male visitor, again increasing the chances for the more recent male to achieve impregnation.

The human penis has evolved to its present form over many thousands of years – and proper upkeep has also evolved. It is strongly urged that men daily apply a superior penis health creme (health professionals recommend Man1 Man Oil, which is clinically proven mild and safe for skin) to maintain the organ's health. Ideally, the crème should contain a range of vitamins, such as A, B5, C, D and E, which can more effectively benefit the penis through topical application. In addition, the best crème will include L-arginine, an amino acid which is a significant aid in keeping penile blood vessels open and receptive.