10 Interesting Facts About Sperm
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Sperm may be sort of funny looking -- like tadpoles in a panic -- but it's a lot more complex and interesting than one might imagine. No other cell (to my knowledge) has been played by Woody Allen, ridden by Zoidberg on a Fantastic Voyage-type episode of Futurama or honored in a memorable movie musical by Monty Python. But how much do you know about these little wigglers on which the survival of your species depends? Well, you’re about to learn a little more.
1. Of course he did
Sperm was first discovered in 1677 by a Dutch microscope maker who used one thing of his own making to examine something else of his own making. LiveScience writes that Antony van Leeuwenhoek reported looking under a microscope and seeing tiny “animalcules” (an archaic term for tiny animals) in a sample of his own semen…semen, he made sure to note, which was an excess from actual sex and not just masturbation.
2. How sweet it isn’t
In a piece called Semen Physiology Anaya Mandal on News-Medical Net says that due to fructose that gets in the mix, semen “tastes slightly sweet.” Far be it for me to argue with a doctor but lemme just say there is a reason a company called Sweet Release went to the trouble of creating a product meant to make semen taste like apple pie: because it doesn’t already taste a thing like apple pie or anything else you’ll find for sale in a bakery. Dr. Mandal does say that the taste of semen can change according to a man’s diet and here you can see a BBC video of a taste test the esteemed news outlet did wherein men switched their diets to see if their wives could taste a difference.
This would come in handy for the female of a species of Ulidid fly, Euxesta bilimeki, which not only expels sperm after mating: they eat it. Science Daily reports on a study from the Instituto de Ecologia in Mexico reported on in the journal Behavior Ecology and Social Biology: 100% of the female flies expelled ejaculate after mating and 25% of those had no sperm left after this expulsion. The theory is that this allows females to choose which males they actually want to father their progeny since it seems they’re able to choose how much sperm to expel, all or just some. (Interestingly, the longer courtship the more likely she is to give all his sperm the heave-ho, leading researchers to think the females in these cases just give in to his advances rather than having to keep rejecting him and then just making sure he’s not the father of her fly babies.)
After experiments in which female flies were given varying diets to see if there was some nutritional reason they were eating the ejaculate, researchers think the reason might be because it provides fluids, since this breed of flies live in very arid areas. Maybe it just tastes like apple pie.
3. Little sneakers
Another way of taste-testing sperm, as a Korean diner discovered to the world’s horror, is by eating squid that is parboiled and undercooked. Thesquid sperm that tried to inseminate a woman’s mouth was an Internet sensation not long ago. How such a thing could happen is explained by squid expert Danna Staaf on the above link to io9, but it starts with the fact that the sperm delivery system of the squid is very different from that of humans. In several species, including squid, butterflies, scorpions, octopi and others, sperm doesn’t travel in semen but in spermatophores or sperm packets; kind of needle-like vessels that are deposited in the female reproductive tract. Staaf calls this squiddy structure “definitely the world’s most complicated sperm,”in this video explaining exactly how spermatophores work.
On io9 Staaf described the process, starting with the spermatophore cap popping off and the ejaculatory apparatus (every spermatophore has one) popping out and everting itself -- turning itself inside out -- pulling the sperm mass with it. But the peculiarity of squid insemination doesn’t end there. In the species known as Bleeker’s squid there are two types of male squid -- sneakers and consorts, which are kind of the Goofus and Gallant of the cephalopod world. Consorts, reports io9’s Joseph Bennington Castro, are larger, more attention-getting of the two, attracting females by “flashing bright colors across their bodies,” depositing the spermatophores in the female oviduct and then guarding her until the eggs are deposited.
Sneakers are not so, well…gallant. They sneak in between a mating pair and chuck a spermatophore in the female's external sperm storage unit so that when the eggs come forward “through her oviduct to a spot near her mouth,” the eggs that don’t get fertilized by the spermatophores of the consort -- who has put in all this courtship time -- will be fertilized by the spermatophores of the sneaker who didn’t do jack. Castro reports that Japanese researchers have found that sneaker sperm are bigger and travel in swarms; they will cluster not only with other sneaker sperm but but with consort sperm and even sperm from a breed of starfish. Figuring they might be attracted to a chemical being released by the other sperm, like CO2, the researchers did experiments in which they released C02 bubble into a tube and found that sneaker sperm “swarmed around it,” while consort sperm did not. Why C02 attracts the sneaker sperm is uncertain but one theory is that eggs may release C02.
Bottom line: squids should probably have their own soap opera, Tentacle Hospital or something. I’d watch it.
4. Animal Adaptations
So squid sperm is pretty fascinating but lots of other animals have intriguing sperm and insemination habits as well.
* Jennifer Welsh of LiveScience reports that the mallard duck has sperm that can kill bacteria and the brighter the bill the stronger the antibacterial effect, thus enabling females to avoid a sexually transmitted pathogen and identify males with better sperm,"
says Melissah Rowe of the University of Oslo.
* Science Magazine reports that moss shoots attract insects -- springtails and mites -- which then carry moss sperm and help fertilization like insects pollinating flowers.
* Christine Dell’Amore of National Geographic reports that some sea creatures like jellyfish, barnacles and sponges do what is known as “spermcasting,” sending their sperm out into the water for females to take, in other words, when it’s time, they just go out and pick up some fertilizer.
* The barnacle, Dell’Amore writes, is a special case: it has the biggest penis in the animal kingdom relative to its size and because it can’t move once it’s glued itself somewhere it uses its super-long wiener and “random penis movements” to seek out partners and deposit sperm in their mantle cavity (don’t we all know a guy like that?). If you think that’s nasty and wish to tell a barnacle to go fertilize itself, well, they already do. “Most barnacles are hermaphrodites though they tend to lean toward one gender,” Dell’Amore writes, but they are capable of self-fertilization.
* The grossest animal kingdom sperm transfer has to be the province of bed bugs. The male of the species has a saber-like penis which he uses to stab the female in the abdomen, releasing sperm into her bloodstream -- her reproductive system is used exclusively for egg-laying says this PBS Gross Science Video. It’s known as “traumatic” insemination, writes Alasdair Wilkins of io9 and all seems slightly less horrid when Isabella Rossellini puts on a bed bug costume and acts it out for you.
5. Glow-in-the-dark sperm
Back in the '80s glow-in-the-dark condoms, as in this scene from Skin Deep, were revolutionary. Now it’s the sperm that glow-in-the-dark and help provide researchers with a whole new way to research what the little swimmers are up to. In 2010 Christine Dell’Amore of National Geographic reported on a study in which germline stem cells of mice were “genetically engineered to be fluorescent” and tagged certain cells within those cells with color to watch their development. The quick process scientist once thought sperm development to be was just not the case: sometimes the stem cells go through several cell divisions, sometimes not, sometimes they start to become a sperm cell and then revert back to being a stem cell.
I would: too much competition to potentially just end up in a Kleenex. That’s not entirely a joke. Even if you were a sperm who got to go on the grand quest for fertilization, study co-author Robert Braun called the fertilization process “surprisingly inefficient,” and says the reason for the enormous amount of sperm is that there has to be a "large initial payload [for those] few cells to make it to the final destination." And yet the process is efficient enough to make contraception an important factor in our lives. Studying sperm on this level could lead to advances in male birth control, like thwarting germline from becoming sperm in the first place.
6. Build a better swimmer
If you’re trying to facilitate pregnancy rather than prevent it, here are a few things you should know about giving your boys a boost:
* The Pharmacy Times reports that a study published in the Journal of Human Reproduction says that spending time in a sauna can lower a man's sperm count and keep it down for as long as six months. It’s called “scrotal hyperthermia.” In the study 10 Finnish men had two 15-minute sauna treatments a week for three months which raised their scrotal temperature by 3 degrees Celsius and impaired both sperm count and motility. Temperature clearly affects sperm health with slightly cooler being better, hence the scrotum being on the outside the body. So it’s not surprising that in a study reported on by Stefan Sirucek of NatGeo on a report from Israel’s Ben-Gurion University of the Negev that sperm motility and structure is strongest in the winter (though that doesn’t mean you shouldn’t try in all the other months….again and again and again).
* Exercise is better for sperm than TV marathons are: Drew Armstrong of Bloomberg reported on a study by Harvard researchers saying that young men who exercised frequently had 73% more sperm than non-exercisers and the sperm counts of those who watched 20 or more hours of TV per week were “almost halved.”
* Nuts are good for your nuts. Shawn Radcliffe of Men’s Fitness reports on a study from the University of California saying that men who ate about two and a half servings of walnuts a day saw an increase in sperm health -- motility, shape and size -- after 12 weeks. Sperm benefit from the omega-3 fatty acids (let’s call ‘em daddy acids) also found in fish oil and other foods.
7. Because what a man really wants is to stick his penis into a huge machine….
Never having had to produce a sperm sample for any medical or commercial purpose I have no idea what it’s like. Maybe, if I had a choice between masturbating the boring old organic way and leaving the job to a torso-high, pulsating machine I would choose the latter.
Bella Battle of the UK Sun reports that a hospital in China is using just such a machine to collect sperm samples from infertile men for testing. At the time of the story (September 2012) about 10 men a day had been using the machine for about six months (presumably not the same 10 men, coming back in disguise to give it another shot because they dug it) according to Doctor Zhu Guoxin, director of the urology department at Zhengzhou Central Hospital. Users can “adjust the machine’s frequency, speed, force and temperature,” Battle writes, and they have to wear condoms.
Still…new awful job: cleaning out the Sperm Extractor. And now, because you’ve been very good, here’s a video. Maybe they’ll get one at your gym.
Having a bad reaction to the semen of the one you love can’t be a fun experience, but there is such a thing as being allergic to semen and to the semen of a specific person. ABC News’ Susan Donaldson James describes a North Carolina couple’s quandary with seminal plasma hypersensitivity. Some symptoms described in the story include itching, redness, burning, swelling, hives plus a pain like “a needle-like sticking in the vagina,” according to the University of Cincinnati’s Jonathan Bernstein, who treated the couple and who believes there are as many as 40,000 such cases in the U.S. Sometime the symptoms are confused with yeast and vaginal infections, James writes.
The treatment to desensitize the wife to the allergy included her undergoing “an intravaginal graded challenge using serial dilutions of her husband's seminal fluid, which were injected via syringe every 15-20 minutes over the course of two to three hours.” It helped and continued to improve and eventually their sex life got back to normal. A lot of people would have just gotten a new spouse…but that’s love for you.
9. It’s on the street
We’ve talked about some interesting sperm delivery systems but the most eye-catching, bar none, is the Sperm Bullitt bicycle, a sperm-shaped bike built for Nordisk Cryobank a leading European sperm bank, used in Copenhagen, as reported -- with pics -- on Copenhagenzine.com. The company was looking for an eco-friendly way to get its cargo around and yes, just like sperm need, it has a cooling system: “Inside the head of the giant sperm cell is a cooler compartment designed so that the metal containers with sperm donations can fit snugly inside and be kept cold.”
It would be the worst getaway vehicle in the world, wouldn’t it? But then…who steals sperm?
10. Love roller-coaster
Most of us have seen those amazing animalcules and the semen they swim in make their grand entrance out of the body, but what you don’t see is the remarkably circuitous route it takes to get to that point. No kidding: men rather fantastically have what amounts to a Krazy Straw in there.
It all starts in the testes which are made up of seminiferous tubules in which sperm are manufactured. HowStuffWorks.com’s Craig Freudenrichand Molly Edmonds put the rate of production at about 4 million per hour.
Once formed, sperm travels to the epididymus, a coiled tube outside the teste (here’s a picture) where they mature and stay. After the penis is erect if there is “sufficient stimulation,” says Medicine Plus (where you can see it all via animation) the sperm travel up, up, up, through the vas defrens which propel them with muscle contractions, then down again to the ampula and the seminal vesicles where they’re mixed with the first of the fluids that make up semen. That fluid contains numerous substances including fructose, potassium, citric acid and the hormone-like substance prostaglandins. This mix goes downward through the ejaculatory ducts past the prostate gland where another milky fluid is added to the mix which helps neutralize the PH of the vagina, and the semen is finally semen.
At this point it goes back up, up, up again through the urethra and zing! Out into the world. Then, who knows? After all that mixology it could end up on the shower floor…or in a sperm bank…or in the aforementioned vagina…or other places on the body (for which you’ll have to look at another kind of website).