Whatever you happen to call it — todger, wang, willy, or dangler — the penis is an odd-looking bit of kit. But beyond the japes and sniggers, it is, of course, vital to the survival of our species.
When you consider the penis as an evolutionary adaptation, it has done remarkably well.
We can all say without too much doubt that our father’s penis worked, as did our grandfather’s, and his father’s, and so on, right back through successive generations until we reach far beyond the birth of humanity.
The penis is ancient. Just in case you were wondering, the oldest known penis dates back 425 million years, and its fossilized remains belong to an arthropod dubbed Colymbosathon ecplecticos, which means “amazing swimmer with a large penis” in Greek.
It’s worth reflecting on its role in our species’ survival next time you are surprised by how easily your penis is “activated.” As far as reproduction is concerned, a false arousal is better than a missed opportunity.
As the author Mokokoma Mokhonoana once wrote, “Even the world’s greatest actor cannot fake an erection.” This leads us on to the first penis fact of the day.
1. Your first erection
Penises are born ready. It is common for babies to exit the womb with an erection. Even before the moment of birth, ultrasound scans sometimes show a fetus with a fully formed erection.
According to a study from 1991, fetal erections occur most commonly during random eye movement (REM) sleep. And, they can happen a number of times each hour. No one is quite sure why, but it might just be our body’s way of testing things out and keeping them running correctly.
2. Your penis is twice as long as you think
A lot of men might take solace in this fact: our penises are longer than they look. In fact, around half of its entire length is housed inside of our bodies.
You might be thinking, “Well, it’s no good to me up there,” but it needs to remain connected to the rest of your anatomy, so it’s probably best that it stays put.
As you can see from the diagram here, the mass of pink erectile tissue — which comprises the so grandly named corpus cavernosum and corpus spongiosum — extends well into the pelvic region, forming a sort of boomerang shape.
I wouldn’t use any of the above as a pick-up line, though.
3. The shoe size myth
Let’s lay this one to rest, shall we? According to a study published in the journal BJU International, there is no correlation between shoe size and penis length.
Although an older study — which was published in 1993 — did find that penile length was related to both height and foot length, it was a weak relationship, and the authors concluded, “Height and foot size would not serve as practical estimators of penis length.”
Also, the International Journal of Impotence Research published an Iranian study looking at other correlations. They concluded that “penile dimensions are significantly correlated with age, height, and index finger length,” but not foot size.
4. ‘Morning wood’
Most men have 3–5 erections every single night — mostly during REM sleep, as with the in utero boys.
Morning wood isn’t as poetic as it sounds.
Also called nocturnal penile tumescence, it’s still not clear why it happens. However, one theory is that it might help to prevent bed-wetting; an erection inhibits urination.
A full bladder is known to stimulate nerves in a similar region to those involved in erections. But because females experience something similar — nocturnal clitoral tumescence — bed-wetting prevention is probably not the entire answer.
Another potential explanation is that REM sleep is linked with switching off cells that produce noradrenaline in the locus coeruleus, which is in the brainstem. These cells inhibit the tone of the penis. So, by reducing the inhibition, the penis becomes erect.
Whatever the reason behind nocturnal erections, they can be useful as a diagnostic tool. If a man has difficulty achieving an erection when awake but becomes erect when he sleeps, it is an indication that there is a psychological issue, rather than a physical one.
However, if he does not get erections during sleep, the issue may be physical.
5. One final erection
So, we’ve established that we can get erections in the womb and during sleep, but this is perhaps even more surprising: the death erection. Also called angel lust or terminal erection, it happens in the moments after death.
Most commonly, it occurs in men who have died from hanging; scientists believe that it may be due to pressure from the noose on the cerebellum. However, it has also been reported following death by a gunshot wound to the head, damage to major blood vessels, and poisoning.
6. You can break your penis
As I’m sure you are aware, there is no bone in your penis, which is fairly unusual for mammals. However, it is still possible to break your penis. It most commonly occurs during vigorous sex, although it has been documented to happen to men who fell out of bed with an erection.
Penile fracture, as it is known, is actually the rupture of the fibrous covering of the corpora cavernosa, which is the tissue that becomes erect when engorged with blood.