Re: how many bastards are there, anyway?

Matthew Rabuzzi (rabuzzi@loc251.tandem.com)
Mon, 19 Aug 1996 09:40:27 -0700

sgf <sfolse@odin.cair.du.edu> writes:
:
: Timothy Taylor's _The Prehistory of Sex: Four Million Years of Human
: Sexual Culture_ (Bantam: 1996) [says:]
:
: " Baker and Bellis believe that male biological mechanisms are geared
: to the expectation of cuckoldry. Human males have relatively large
: testicles and produce far more sperm than they seem to need. In normal
: conception a single egg is fertilized by a single sperm. So what are the
: other 2,249,999 sperm from an average 2.25-million-sperm ejaculation up to?

Right off the stick, this book loses credibility. You might ejaculate a
paltry 2.25M sperm at the end of a hard day's night at stud, I suppose,
but a normal average human ejaculation will be two orders of magnitude greater:

According to Anthony Smith (_The Body_, 1968), the avg ejaculation is 2-7 cc
of semen, which is 90% water, containing perhaps 200,000,000 spermatozoa.
The Encyclopedia Britannica ups this estimate to 300-400M per ejaculation.

I can testify -- literally -- to these numbers' reasonableness. I used to
be a sperm donor at California CryoBank in Palo Alto (you get paid for doing
what you'd do anyway, and they have a good selection of magazines and videos).
I remember thinking, after my initial semenalysis, "Wow, that's still enough
left over to populate Japan!" And that's because the analysis is done after
a trial freezing and then returning to testicle temperature, i.e. simulating
a syringe fertilization, and the freeze/thaw typically kills 50-90% of the
sperm cells. In addition to count, they examine motility, by two metrics.
There's divagation -- do they swim straight to the target, or yaw all over
the place, or tend to the left, or what (I don't think Coriolis force is a
factor here). And there's speed, which I recall was 185 microns/second.
Now if a 5-micron-long spermatozoon were scaled to the height of an average
man, that would be equivalent to 215 feet/sec or close to 150 mph.
Slower than a botfly, but heck, this is a *swimming* speed.

Matthew "no sonic booms, but makes lots of noise other ways" Rabuzzi