funny and interesting facts

1. The human cell contains 75 MB of genetic information
2. A sperm 37.5 MB.
3. In a milliliter, we have 100 million sperms.
4. On average, one ejaculation releases 2.25 ml in 5 seconds.
Using basic math we can compute the bandwidth of the human male penis as:
(37.5MB x 100M x 2.25)/5 = (37,500,000 bytes/sperm x 100,000,000 sperm/ml x 2.25 ml) / 5 seconds = 1,687,500,000,000,000 bytes/sec = 1,687.5 TeraBytes/sec

That’s in the order of Petabytes. After laughing about it, you may wonder if the calculation is correct. Well, keep reading for our ordinary investigations in this profound question that will surely cheer up any casual conversation.

THE CD-SPERM COINCIDENCE

Information in our genome is encoded as a sequence of nucleotides in the DNA. Knowing the total number of relevant nucleotides (forming a base pair) is pretty straightforward: in a reference haploid human genome there are some 3,1 billion of them. Since there are four types of nucleotides in our DNA (the famous “TGCA” letters, or GATTACA for your mnemonics), each base-pair represent 2 bits of information, meaning that would you to record all of them it would take some 6,2 billion bits, which translates to around 740 megabytes. Roughly the data that fits a single CD.

Now, as a side information, we are in fact diploid, having two of each autosome and two sex chromosomes. Meaning we have double that calculated value of data in our cells, which amounts to 1,44 Gigabytes. Each tiny one of your 100 trillion cells has double the data of a CD encoded in a tiny strand of DNA.

But back to the human penis data bandwidth.

The human sperm is indeed haploid – half the data that will be joined with the other half in the human egg –, which means that it does have around 740 Megabytes of raw genetic data as we calculated at first.

Which also means it’s a funny coincidence a single sperm has around the same amount of data as a single CD. Sperm data capacity is a reference far more interesting than Beethoven’s 9th Symphony, by the way.

Well, the calculation quoted at the beginning of this post is wrong, a sperm has around 20 times 37.5 MB. Now, correcting that error, and knowing that the values for average sperm count and ejaculation volume are correct, you would have:

(6.2 x 10^9 bits/sperm) x (100 x 10^6 sperm/ml) x (2.25 ml) / 5 seconds
=
1395 x 10^15 bits / 5 seconds
=
2.8 x 10^17 bits/sec
=

31 Petabytes/sec

That’s the
human penis data bandwidth.

You could have simply multiplied the initial value by 20 to get to roughly the same value, but anyway, an average human penis would be transmitting 31 Petabytes, or 31 quadrillion bytes of raw data per second during its climax performance.

That’s more than all data processed by Google every day; two times all the data produced by the Large Hadron Collider per year; thirty times all the users’ photos in Facebook – already roughly 10 billion photos. It far exceeds the bandwidth of any current data transmission technology.

Amazing, huh? Say hello to our little friend. But let’s delve into some related issues.

MP3 YOUR SPERM?

Just as the original audio CD format may store only a single Beethoven’s 9th Symphony performance, but hundreds of songs in the compressed MP3 format, data in our genome could also be compressed. Perhaps it’s just as wasteful?

For starters, only around a third of the genome is unique, 10% or less seems to be devoted to genes, and a mere half of that would be coding DNA. Which, ten years ago, led to thesuggestion that a haploid human genome would have only around 30 Megabytes of actual information (coincidentally, a value close to the initial one in this post).

But would our genome be as bad a format as an audio CD? Audiophiles can clearly distinguish between a lossless audio format and the lossy MP3 one. Similarly, recent research suggests the “junk DNA” is in fact not junk, which would make compressing the genome data much more difficult. We still know far too little on the subject – we don’t even know for sure how many genes we have – but it’s not wild to speculate that our genome may not be “wasting” too much storage in useless junk.

Another thought to consider is that, as mentioned earlier, each and every of the 100 trillions of the cells in our bodies has 1,44 Gigabytes of genetic information… do the math and I don’t think there’s a unit of information to account for all the genetic data a single human being is carrying around. That would be some 144 trillion Gigabytes.

Only thing is, almost all of our cells have (or should have) the exact same genetic information (some chimeras apart), so that would not be that impressive. In fact, that makes our reproductive cells more impressive, since each one of them is genetically unique. If all of the sperm going through a human penis had an identical genome, then the information transmitted would be that of a single sperm.

Which leads us to some further interesting numbers. By maturing each ovum (egg), women are producing around a CD worth of unique genetic information each menstrual cycle. In contrast, men are constantly producing around 200 million sperm per day, that is, around 30 Petabytes of unique genetic data. No wonder the urge to be fruitful and multiply.

On the other hand, you can also grasp that this is a lot of wasted genetic data. As folks ateverything2 noted, “if you consider signal to noise, the figures come out much differently”. Usually only a single sperm fertilizes the egg, all those petabytes wasted. That would make only a single CD in five seconds, or 150Mb/s, something close to broadband Internet in Japan.

Even that lowly value can be interesting if you crunch more numbers. Around 4.4 babies are born every second worldwide, which establishes that at least 4.4 conceptions must be happening, translating into 740Mb x 4.4 /sec or something like 3 Gigabytes of genetic data being successfully “transmitted” each second by men all over the world, warranting the continuity of our species.

Considering only a small fraction of sexual intercourse results into a successful conception, and all the other means by which sperm may be liberated, the total data bandwidth of all human penises probably far exceeds all the current artificial means of human communication. Which is mostly wasted too, or haven’t you seen your kitten video today? Or aren’t you reading this?

As “LJ” noted on e2, penises, however, “puts the local in Local Area Network. It would take a special breed of man to achieve a segment length of more than a few feet, and network topologies are best left as an exercise for the reader.”