Here's a 15th century illustration of an English surgical procedure. Fun!
See the full blog — Discarded Image | Discarding Images.
Here's a 15th century illustration of an English surgical procedure. Fun!
See the full blog — Discarded Image | Discarding Images.
Stanley Milgram's "Obedience to Authority" experiments are infamous classics of psychology and social behavior. Back in the 1960s, Milgram set up a series of tests that showed seemingly normal people would be totally willing to torture another human being if prodded into it by an authority figure.
The basic set-up is probably familiar to you. Milgram told his test subjects that they were part of a study on learning. They were tasked with asking questions to another person, who was rigged up to an electric shock generator. When the other person got the questions wrong, the subject was supposed to zap them and then turn up the voltage. The catch was that the person getting "zapped" was actually an actor. So was the authority figure, whose job it was to tell the test subject that they must continue the experiment, no matter how much the other person pleaded for them to stop. In Milgram's original study, 65% of the subjects continued to the end of the session, eventually "administering" 450-volt shocks.
But they weren't doing it calmly. If you read Milgram's paper, you find that these people were trembling, and digging nails into their own flesh. Some of them even had seizure-like fits. Which is interesting to know when you sit down to read about Michael Shermer's recent attempt to replicate the Milgram experiments for a Dateline segment. Told they were trying out for a new reality show, the six subjects were set up to "shock" an actor, just like in Milgram's experiments. One walked out before the test even started. The others participated, but had some interesting rationales for why they did it — and a simple ingrained sense of obedience wasn't always what was going on.
Our third subject, Lateefah, became visibly upset at 120 volts and squirmed uncomfortably to 180 volts. When Tyler screamed, “Ah! Ah! Get me out of here! I refuse to go on! Let me out!” Lateefah made this moral plea to Jeremy: “I know I'm not the one feeling the pain, but I hear him screaming and asking to get out, and it's almost like my instinct and gut is like, ‘Stop,’ because you're hurting somebody and you don't even know why you're hurting them outside of the fact that it's for a TV show.” Jeremy icily commanded her to “please continue.” As she moved into the 300-volt range, Lateefah was noticeably shaken, so Hansen stepped in to stop the experiment, asking, “What was it about Jeremy that convinced you that you should keep going here?” Lateefah gave us this glance into the psychology of obedience: “I didn't know what was going to happen to me if I stopped. He just—he had no emotion. I was afraid of him.”
If you are a lady, and you think you might be pregnant, you can take an at-home test to find out. You simply pee on a stick. Whether the results are measured in pink lines, blue lines, plus and minus symbols, or a "pregnant"/"not pregnant" digital readout, all the home pregnancy tests on the market are really looking for the same thing — Human chorionic gonadotropin (HCG).
HCG is a pregnancy hormone. It's produced by the placenta, a temporary organ that only forms in female bodies when an embryo has attached to the uterine lining. And so it was kind of weird when a male friend of a Reddit user known as CappnPoopDeck peed on a home pregnancy test and it came back positive.
Turns out, HCG can show up in men, too. And when it does, bad things are happening. You might have seen this story on Gawker earlier this week, but the science behind it is so crazy that I wanted to discuss it in a little more depth.
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Watch it eat. ERMAHGERD. It's almost enough to make you forget about the horrors of the echidna penis. Almost. Until you notice that the puggle has five legs. So, there's that.
Yesterday, I posted a photo of Glaucus atlanticus — a strange little creature, related to mollusks, which floats through the ocean and eats (among other things) the jellyfish-like Portuguese Man-Of-War.
In response, marine biologist Christopher Mah sent over this video, in which two specimens of Glaucilla marginata — a smaller relative of Glaucus atlanticus — nibble on the still-living flesh of a colonial organism called a blue button. This proves to be cuter than it sounds.
Part of what makes the video so mesmerizing is watching the Glaucilla marginata move around. These creatures travel in a very laid-back way. Inflating a gas bubble in their stomachs, they float around on their backs, wherever the waves will take them. That bubble seems to lead to some endearing, baby-sloth-like flips and turns as they try to position themselves to take bites out of the blue button. OM NOM NOM.
Here's a fun fact: Did you know that you can get tapeworms in your brain? You know that you can get a tapeworm from eating infected meat. But when people have tapeworms in their guts, they secrete tens of thousands of eggs a day. And those eggs can end up on food, or other things that people put into their mouths. For some reason—nobody is really sure why—tapeworm eggs that are ingested by humans never mature into adults. Instead, they remain in a larval stage and hang out in a host's bloodstream. Sometimes, they make it to the brain. And, apparently, this happens often enough that it has an actual medical name: Neurocysticercosis.
The good news is that these things are mostly harmless. They don't seem to hurt your brain at all while they're alive. The bad news: As soon as the larvae die, your body's immune system seems to suddenly realize they exist and it goes into overdrive—triggering seizures, loss of feeling in the body, and sometimes leading to death.
Scientific American blogs has the story of one woman in California who had this happen to her. To save her life, surgeons had to remove a calcified tapeworm larva from her brain.
Sara Alvarez was afraid.
It was December 20, 2010, in Sunnyvale, Calif., a town that lives up to its name. The West Coast winter, not as long or as harsh as seasons in the East, gave her the opportunity to take her youngest child out for an afternoon stroll.In the fading light of dusk, Alvarez, too, began to fade. She lost the feeling in her right leg. Her right foot followed suit. She couldn’t lift or move her right hand. She was weak, and her body was numb.
The National Institutes of Health classifies neurocysticercosis as the leading cause of epilepsy worldwide, and the World Health Organization (WHO) estimates that tapeworms infect 50 million people globally. The CDC says an estimated 1,900 people are diagnosed with neurocysticercosis within the United States yearly.
Read the rest of the story at Scientific American blogs. (WARNING: Surgery images!)
"Everything you never wanted to know about the mites that eat, crawl, and have sex on your face". How can you say, "No", to that headline?
Ed Yong has a great post up today at Not Exactly Rocket Science about Demodex folliculorum and Demodex brevis, two species of mites which spend their entire lives on human skin. Humans aren't born with these mites. But by the time you are 40 years old, it's almost guaranteed that you are playing host to a few of them.
The bad news: They are having sex on your face.
Their favourite hook-up spots are the rims of your hair follicles. After sex, the female buries into the follicle (if it’s D.folliculorum), or into a nearby sebaceous gland (if it’s D.brevis). Half a day later, she lays her eggs. Two and a half days later, they hatch. The young mites take six days to reach adulthood, and they live for around five more. Their entire lives play out over the course of two weeks.
The good news: They don't poop—in fact, they don't even have an anus.
The bad news again: All that waste just builds up in their bodies. Demodex are, by nature, chronically constipated. Only after they die, and their bodies disintegrate, do they finally get to let it all go. All over your face.
Scale worms are usually small, and there are many different species that fall under the common name. At least one, Arctonoe vittata, famously enjoys a complex relationship with starfish. The worm lives in the starfish's sucker feet. There's a possibility that this commensal arrangement—neither animal really gets any special benefit from having the other around, but they aren't hurt by it either. On the other hand, a 1979 research paper found that A vittata and its starfish host will seek each other out—mutually—through mazes. The starfish will even choose to move toward the worm over its favorite food. And it's still not really clear why that is.
So these are interesting worms. In fact, they can look damn-near cute—almost like little roly-poly pill bugs. But those are the small ones. This guy is different.
Echidnas are one of those weird Australian animals that seems to have been pieced together from leftover bits of other animals. Mammals that lay eggs, echidnas are covered in pointy hedgehog-like spines, but with a long snout and sticky tongue of an anteater.
Also, the males have a four-headed penis.
Not kidding. One shaft, four heads. Which is odd, because the female echidna reproductive tract only has two branches. Some of the stuff I've read this morning says that the male echidna mates using only two of his four heads at a time. Then, he'll find another lady echidna and let the other two heads have a turn. Another option, presented by National Geographic: He mates twice with each lady echidna, using first two heads, and then the other two.
National Geographic has helpfully provided visual evidence of this four-headed penis.
I'm putting the photo under a cut. Partly for comic effect, and partly because what is seen can never be unseen.
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Banana slugs are hermaphrodites. Every slug has both a penis (which pops out of a pore on its head, like you do) and a vagina. Or, rather, every slug should have a penis. The truth is that quite a few of them don't and the story behind that discrepancy is rather strange and horrifying. Since there's little I love more than strange and horrifying stories from nature, you get to hear all about it.
At The Last Word On Nothing, Cassandra Willyard tells the story of a nearly 100-year-old effort by scientists to understand why some banana slugs appear to be missing their penises, or have penises that are stunted. We have known since 1916 how those penises came to be missing. Willyard describes the situation, which you can also watch in action in the video above:
Banana slugs begin their mating with a few vicious love nips. Then the animals curl around each other, forming a bright yellow yin-yang symbol. Next, they insert their penises. (Remember, they both have one.) In some cases, one slug provides sperm and the other slug receives it. More often, the slugs swap sperm. Copulation can last many hours. Then, in most cases, the slugs withdraw and part ways.
Heath caught a couple of slugs in the act. He noted the biting and the insertion. And then Heath observed something puzzling. As the slugs were withdrawing their penises, “one of the animals turned its head and commenced to gnaw upon the walls of the organ,” Heath wrote. The biting was “unusually vigorous,” he added, “and within a very few minutes the penis was entirely severed.”
The confusing part is why the hell they do this to each other.
Willyard says the best idea so far is that the penis eating represents a sort of sperm competition—a way of ensuring that the slug you just mated with isn't going to get a shot at mating with anybody else. But that's really just an educated guess.
What I like best about this story (besides the shock and awe) is that it handily illustrates one of the difficulties inherent in scientific research. In many cases, it's quite easy to answer the question, "What happens?" A century ago, scientists could easily observe and document the penis-eating behavior. All it took was somebody with sufficient interest in the question that they were willing to spend time watching many, many examples of slug sex.
But the "Why" is sometimes trickier.
Video courtesy University of California Santa Cruz graduate student Brooke Miller. See more of her work on banana slug sex.
Also included: Some fun with Latin vocabulary. Did you know that dolichophallus means "long penis"? You're welcome.
Via Ed Yong
To be fair, there are really only a few ways that London's Hunterian Museum would end up with the uterus of a young woman floating in a jar. Given that the museum is home to surgical specimens, many of which were collected in the days before surgery involved anesthesia, it's easy to guess that the story behind the uterus is not a pretty one.
But at The Chiurgeon's Apprentice blog, we learn that the story is even more grisly than you might have suspected. In fact, it belonged to a woman who committed suicide by drinking arsenic in 1792. She was, at the time, a month or so pregnant. Medical historian Lindsey Fitzharris writes about the autopsy:
In his [autopsy] report, Ogle remarked that her stomach contained ‘a greenish fluid, with a curdy substance…an effect produced by the arsenic’. He also noted that there was ‘an uncommon quantity of blood in the vessels of the ovaria and Fallopian tubes’ and that it was ‘evident, from this circumstance, that conception had taken place’.Nevertheless, when told that the date of her last period had only been ‘a little more than a month before her death’, Ogle began to question whether Mary had been pregnant when she died.
Curious to know the truth, Ogle removed the ‘organs of generation’ and gave them over to the famous anatomist, John Hunter, whose interest in pregnant cadavers was well known. Hunter injected the arteries and smaller vessels of the uterus with a wax-like substance so that ‘the whole surface became extremely red’. The uterus was then split open and the ‘inner surface of the cavity…was examined with a magnifying glass’...
Via Deborah Blum
So. That happened.
Interesting tidbit for those of you too horrified to watch: Hissing cockroaches apparently give birth upside down with their lady parts up in the air.
Another thing I learned: Animals giving birth is apparently a fairly popular YouTube genre. Check out the sidebar for cats, snakes, and more cockroaches.
A hearty thanks to Amos Zeeberg, without whom I would never have seen this horrible thing.