sperm

Image of a deer mouse from Seney Natural History Association, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=29576617 Deer mice are known for being quite promiscuous. In fact, it is not uncommon to find a litter of deer mice with multiple fathers. Dr. Hopi Hoekstra and colleagues at Harvard University's Department of Organismic and Evolutionary Biology discovered that the tail of deer mice sperm have longer midsections than found in monogamous mice. What this means is that their sperm can swim better and faster, thereby reaching an egg sooner than sperm from other…
I've written several times over the years about the overblown claims of harm attributed, largely—but not exclusively—by cranks, to cell phone radiation. It's been claimed that radiation from cell phones can cause brain tumors (there's no convincing evidence that this is true), breast cancer (the evidence for these claims is so incredibly flimsy—and featured by Dr. Oz, to boot!—that this is not a credible claim), and a wide variety of other health issues. Indeed, if you believe the cranks, the mobile phone companies are the equivalent of tobacco companies denying that their products cause…
The tl;dr: maybe a little but for benign reasons. If fertility is important to you and you are a man, don’t put hot things in your pockets. This may fall into the category of switching from tidy whities to boxer briefs. A study came out in September suggesting that it does. It is a meta-analysis by Jessica Adams et all, published in Environmental International, called “Effect of mobile telephones on sperm quality: A systematic review and meta-analysis.” The study considered the effects of radio-frequency electromagnetic radiation (RF-EMR) on sperm motility (movement), viability, and…
So I was browsing the internet for info on G-protein coupled receptors and ended up finding some interesting facts about sperm. It turns out sperm don't just swim blindly, hoping to randomly bump into eggs. Instead, like bacteria, sperm can sense their chemical environment and adjust their swimming accordingly. Sperm have a sense of smell. The (g-protein coupled) olfactory receptors in our noses that activate our sense of smell were discovered in 1991, an amazing discovery that earned the 2004 Nobel prize for physiology or medicine. The receptors sit on the surface of the cells up high in our…
One night of passion and you're filled with a lifetime full of sperm with no need to ever mate again. As sex lives go, it doesn't sound very appealing, but it's what many ants, bees, wasps and termites experience. The queens of these social insects mate in a single "nuptial flight" that lasts for a few hours or days. They store the sperm from their suitors and use it to slowly fertilise their eggs over the rest of their lives. Males have this one and only shot at joining the Mile High Club and they compete fiercely for their chance to inseminate the queen. But even for the victors, the war…
This article is reposted from the old Wordpress incarnation of Not Exactly Rocket Science. Getting excited when fish produce sperm would usually get you strange looks. But for Tomoyuki Okutsu and colleagues at the Tokyo University of Marine Science and Technology, it's all part of a day's work. They are trying to use one species of fish as surrogate parents for another, a technique that could help to preserve species that are headed for extinction. Okutsu works on salmonids, a group of fish that includes salmon and trout. Many members of this tasty clan have suffered greatly from over-…
According to a paper to be released in the September issue of the journal "American Naturalist", the number of sperm a male ejaculates may be correlated to his attractiveness as measured by the females in the population. The idea came forth after scientists at University College London and the Oxford University mathematically modeled the optimal "sperm load" to maximize daddiness across a range of mating patterns. The research, which took place late one Friday night at the corner bar, was one of several proposed ideas to "settle a bet" between two of the scientists. The results suggest that…
Remember all the fun you had with the Great Sperm Race game a while back? Well, now you can step it up a level with Sperm Rider. In this game you play a delighted little guy in a cowboy hat, riding on a giant spermatozoa through a city drawn crudely in crayons. Using your "seed of destruction", set about squishing the local populace, and fend off attacks from tanks, helicopters and jet planes by deflecting their missiles with your long tail. It's all set to brilliant music and has very little to do with any kind of science, but I like it anyway. Just make sure you don't "ruin everything…
Sex is fun, but it's nothing compared to the thrilling life-or-death struggle spawned by passionate, unprotected lovemaking. Thankfully, to promote Channel 4's The Great Sperm Race, Flash game maestro Johnny Two Shoes has conceived a game that puts you in the cockpit of a humble gamete struggling to become whole again. Like a super-fecund cage match, 250 million enter, but only one leaves. Can you safely navigate the acid-filled folds of the vagina and outwit the hungry leukocytes to bury yourself into the egg in an explosion of zygotic glory? Find out now!
Then you need to head over to The Oyster's Garter and read Miriam Goldstein's incredibly funny post about the problems of male sea squirts. Apparently, if you're a sea squirt, the size of your sperm is related to your environment and mostly the number of other sea squirts in your environment. Usually, I'm not attuned to the issues of broadcasting spawn or the lives of those who live under a dock, but Ms. Goldstein channels Dr. Tatiana so well, I found myself sympathizing and laughing out loud at the struggles of the tunicates. Sometimes extremely handsome pleats just aren't enough.