Your sense of smell probably has a bigger impact on your life than you think. In fact, there are scientists who study how smells affect the choices we make every day, including choosing partners. So, when it comes your own B.O., you have a couple of options: you can try to mask the stink with deodorant, or you can make the best of what you’ve got. According to this study, if you go with the latter, you’d might think about joining a CSA, because the more produce you eat, the better your B.O. smells. And there’s a bonus: your skin gets a sexy “glow” from the carotenoids. But be careful not to overdo it–you don’t want to end up stuck on the toilet looking like Trump!
“Human axillary sweat may provide information pertaining to genetic relatedness and health status. A significant contributor to good health, both in the short and longer term, is a diet rich in fruit and vegetables. In this study we tested whether dietary fruit and vegetable intake, assessed indirectly by skin spectrophotometry (assessing dietary carotenoid intakes) and subjectively by food frequency questionnaire, were associated with more pleasant smelling sweat. Read More
Do you like your steak black and blue or just blackened? According to this study, your preference may depend on the emotions you feel when looking at raw meat. Here, researchers first showed 1046 Norwegian subjects pictures of either a rare or a well-done hamburger and asked them to indicate whether the image elicited “fear, disgust, surprise, interest, pleasure, or none of these.” The subjects were then told to rate their likelihood of eating burgers done to different levels (see figure below). Although it’s hard to untangle cause and effect in this case, those subjects who experienced interest or pleasure while looking at the rare burger were more likely to want to eat rare meat than those who experienced fear or disgust. My question is this: who are these people who are afraid of hamburgers?
Hamburger hazards and emotions.
“Previous studies indicate that many consumers eat rare hamburgers and that information about microbiological hazards related to undercooked meat not necessarily leads to more responsible behavior. With this study we aim to investigate whether consumers’ willingness to eat hamburgers depends on the emotions they experience when confronted with the food. Read More
It’s well known that human sperm have a long way to travel in the female body if they are going to fertilize an egg. But that’s nothing compared to the tortuous path taken by the sperm of leaf beetles. Female leaf beetles have a spiral-shaped tube through which the sperm must travel, including turn reversals to make this maze even trickier (the “spermathecal duct”). So, how do these beetles ever get lucky? Well, according to this research, it’s all about hardness… of the female! The female tubes are uniformly stiff, whereas the sperm are soft at the tip and gradually stiffen along their length, a combination that maximizes the sperm’s speed through the tube. Sorry, ducks – looks like the corkscrew penis doesn’t make you that unique after all!
“It is well known that sexual selection is the main driving force of substantial diversity of genitalia found in animals. However, how it facilitates the diversity is still largely unknown, because genital morpho/physical features and motions/functional morphology of the structures in sexual intercourse are not linked for the vast majority of organisms. Here we showed the presence of material gradient and numerically studied an effect of stiffness gradient of the beetle penis during its propulsion through the female duct. Read More
We’ve heard of intractable hiccups (which can be cured, FYI, by digital rectal massage), but here’s a new one: intractable sneezing. This article reports the case of a young girl who sneezed up to 2,000 times a day for 3 months. She did not get better despite being seen by numerous doctors and being treated with everything from antihistamines to corticosteroids, leading the doctors to believe it was probably psychological. Or maybe she was just allergic to sneezing?
“We report a case of hysterical, intractable paroxysmal sneezing in an adolescent girl. The patient had been observed by two pediatricians, an allergist, an emergency room physician, and a chiropractor. She had been treated with antihistamines, epinephrine, corticosteroid nasal spray, and a 1-week course of an oral corticosteroid without improvement. She was referred for evaluation of an allergic etiology before continuing her workup with a computed tomographic head scan. The patient had been sneezing almost daily for 3 mo up to 2000 times a day. Read More
We previously reported that dogs prefer petting to vocal praise. Well, according to this study– which involved putting dogs in an fMRI machine–it turns out that most dogs prefer praise to food, and will even choose their owner over food when given the choice. Talk about man’s best friend! (PS: For a cute dose of doggie fMRI, check out the figure below.)
“Dogs are hypersocial with humans, and their integration into human social ecology makes dogs a unique model for studying cross-species social bonding. However, the proximal neural mechanisms driving dog-human social interaction are unknown. We used fMRI in 15 awake dogs to probe the neural basis for their preferences for social interaction and food reward. In a first experiment, we used the ventral caudate as a measure of intrinsic reward value and compared activation to conditioned stimuli that predicted food, praise, or nothing. Relative to the control stimulus, the caudate was significantly more active to the reward-predicting stimuli and showed roughly equal or greater activation to praise versus food in 13 of 15 dogs. Read More
If you are one of the unlucky who get carsick, you probably know quite well that being the driver is much less nauseating than being a passenger. But why is this the case? Prior to this study, some scientists thought it had to do with mismatching information from different senses (your eyes may say you are not moving, but your body says differently), and some thought it was due to overstimulation of the inner ear. In this study, researchers from the Israeli Naval Hyperbaric Institute separated different aspects of the experience by having pairs of participants sit in a specially built “nauseogenic” rotating car. In some cases, the subjects’ heads were even yoked together using customized helmets (see Figure 1 below), allowing one person to control the head movements and rotations of the other. The scientists found that being in control of movement seemed to be important in reducing motion sickness — with all other stimuli being equal, the passengers still felt sicker. Teacups, anyone?
“The central hypothesis of the work is that the dimension of control-no control plays an important role in motion sickness. Although it is generally agreed that having control over a moving vehicle greatly reduces the likelihood of motion sickness, few studies have addressed this issue directly Read More
Swordfish are among the fastest swimmers on Earth, reportedly reaching speeds of up to 60 mph. Their “sword” appendage helps them slice through the water, but they still have to deal with friction and drag from their less-pointy head. According to this study, the fish counter this friction through a clever mechanism: lube! These scientists discovered an oil-producing gland on the swordfish head that helps to lubricate the skin and reduce drag, increasing swimming efficiency. How slick is that?!
“The swordfish is reputedly the fastest swimmer on Earth. The concave head and iconic sword are unique characteristics, but how they contribute to its speed is still unknown. Recent computed tomography scans revealed a poorly mineralised area near the base of the rostrum. Here we report, using magnetic resonance imaging and electron microscopy scanning, the discovery of a complex organ consisting of an oil-producing gland connected to capillaries that communicate with oil-excreting pores in the skin of the head. Read More
Like many amazing ocean animals, sharks are in trouble. And unlike whales and otters, their bad rap can make it difficult for sharks to get the protection they need to stave off extinction. But why do people fear sharks so much? According to this study, it’s not just their big teeth, but also the type of music played during video documentaries that might be to blame. In fact, volunteers who watched shark-infested clips of “Blue Planet Seas of Life” with the associated (ominous) music were more likely to rate sharks as scary compared to people who watched the same clip while listening to uplifting music from other segments of the documentary. Not only that, but listening to scary music made viewers less likely to be willing to donate money to shark conservation efforts. Shark Week, are you listening?
“Despite the ongoing need for shark conservation and management, prevailing negative sentiments marginalize these animals and legitimize permissive exploitation. These negative attitudes arise from an instinctive, yet exaggerated fear, which is validated and reinforced by disproportionate and sensationalistic news coverage of shark ‘attacks’ and by highlighting shark-on-human violence in popular movies and documentaries. Read More
“It all started with an enquiry from a nurse,” Dr Karl Kruszelnicki told listeners to his science phone-in show on the Triple J radio station in Brisbane. “She wanted to know whether she was contaminating the operating theatre she worked in by quietly farting in the sterile environment during operations, and I realised that I didn’t know. But I was determined to find out.” Read More
As we’ve discussed before, ice-cream headache (a.k.a. “brain freeze”) is a real phenomenon, and scientists are actively studying it. But before they can understand in detail the physiological events surrounding brain freeze, they must first have a robust way of inducing it. Here, scientists compared two different methods of inducing ice-cream headaches: pressing an ice cube to the roof of one’s mouth vs. chugging ice water. It turns out that the ice water gave volunteers more, and worse, headaches that they described as “stabbing pain.” Something to (literally) keep in mind the next time you chug a Slurpee.
“BACKGROUND: There are various studies on experimentally provoked ‘ice-cream headache’ or ‘headache attributed to ingestion or inhalation of a cold stimulus’ (HICS) using different provocation protocols. The aim of this study was to compare two provocation protocols. Read More