Wondering what’s been going on lately in the field of chasmology (the scientific study of yawning)? Well, we still don’t really understand why people yawn, but we can add another contender to the list of theories: brain cooling. In this study, the authors showed subjects photos of people yawning to determine their susceptibility to “yawn contagion.” They found that the subjects were more likely to “catch” yawns in the summer compared with the winter. Although there are a number of things that change with the season, the only variable found to correlate with yawning was higher temperature, suggesting that yawns might have a function in cooling the brain (via the release of heat into air in the lungs). So the next time someone gets mad at you for yawning when you should be paying attention, just tell them your brain is hot and you’re cooling it off.
A thermal window for yawning in humans: Yawning as a brain cooling mechanism.
“The thermoregulatory theory of yawning posits that yawns function to cool the brain in part due to counter-current heat exchange with the deep inhalation of ambient air. Consequently, yawning should be constrained to an optimal thermal zone or range of temperature, i.e., a thermal window, in which we should expect a lower frequency at extreme temperatures. Read More
Plagued by bedbugs? Just want to avoid them in the first place? Well, listen up: apparently, bedbugs have very specific color preferences when it comes time to choosing their hiding places. In this study, the authors put bedbugs in dishes containing tent-like “harborages” of different colors (see figure below — the tents are actually kind of cute). They then allowed individual bedbugs to choose a tent and recorded which color each one chose. Turns out that the bugs are big fans of red and black, and seem to be least interested in yellow and green. Just something to keep in mind the next time you head out to buy new sheets…
“Behavioral bioassays were conducted to determine whether bed bug adults and nymphs prefer specific colored harborages. Two-choice and seven-choice behavioral color assays indicate that red (28.5%) and black (23.4%) harborages are optimal harborage choices for bed bugs. Yellow and green harborages appear to repel bed bugs. Harborage color preferences change according to gender, nutritional status, aggregation, and life stage. Read More
Binge-watching TV is a relatively new phenomenon — 10 years ago, the only way you could do it was via box sets of DVDs or the occasional marathon on TV. Now, Netflix, Hulu, and many other providers let you watch as many episodes of “Battlestar Galactica” as you can handle in one sitting. In this study, scientists used an online survey to measure how much TV qualifies as a “binge” and how binge-watching makes people feel. They found that watching more than two episodes of the same show in a sitting puts you in binge territory, and binge-watching is correlated with “anticipated regret” (I’m gonna regret this in the morning) and “goal conflict” (binge-watching is keeping me from doing other activities I’d like to do). To address the problem of binge-watching, and associated sedentary behavior, the authors suggest that “online streaming services include in-built interruptions after a number of consecutive episodes have been viewed.” We throw this to you, dear readers — good idea, or just a party pooper?
“Binge watching is a relatively new behavioural phenomenon that may have health implications. The aim of this study was to estimate the frequency of, and identify modifiable factors associated with, TV binge watching. A total of 86 people completed an online questionnaire assessing self-efficacy, proximal goals, outcome expectations, anticipated regret, automaticity, goal conflict and goal facilitation, and self-reported binge watching over the last week. Read More
Have you ever wondered how fast your fingernails grow? And whether they all grow at the same rate? Or perhaps you’ve noticed that your fingernails grow more slowly than they used to? If so, you and William B. Bean have something in common! Professor Bean painstakingly measured the growth of his fingernails for decades, and he published the minutia of these measurements after 20, 25, 30 and 35 years. The full texts of these papers are a delight to read. And the findings? Well, we’ll let Professor Bean speak for himself! (Be sure to check out the fantastically detailed chart of his fingernail growth rates below…)
“When I first began to measure the rate of nail growth, I scored marks on all my nails. Within a few months I found that each nail had its own pace. This was clearly distinguishable even by the rather crude method that I used. Some nails grew rapidly; some, in an intermediate phase, less rapidly; and some, slowly. The differences were small but regular. There was consistency in the variation, so if I applied a ratio I could tell by measuring one nail what the others were doing, and this I did on several occasions. In simple terms, toenails grow more slowly than nails of the hand, and the nail of the middle finger grows more rapidly than the nails of either the thumb or the little finger or the other two middle fingers.”
“A 35-year observation of the growth of my nails indicates the slowing of growth with increasing age. The average daily growth of the left thumbnail, for instance, has varied from 0.123 mm a day during the first part of the study when 1 was 32 years of age to 0.095 mm a day at the age of 67. Read More
During times of flood, certain species of ants work together to build rafts out of… themselves! Not only that, previous work has also shown that some ants use highly buoyant eggs and larvae at the base of the raft to help keep the entire contraption afloat. Here, scientists from UC Riverside tracked individual ants during multiple rounds of raft building and discovered that individual ants return to their same position on Anty McAntface during sequential floods, much like members of a ship’s crew manning their stations. As the short clip below produced by UC Riverside says: “All Ants on Deck!”
Ant workers exhibit specialization and memory during raft formation.
“By working together, social insects achieve tasks that are beyond the reach of single individuals. A striking example of collective behaviour is self-assembly, a process in which individuals link their bodies together to form structures such as chains, ladders, walls or rafts. To get insight into how individual behavioural variation affects the formation of self-assemblages, we investigated the presence of task specialization and the role of past experience in the construction of ant rafts. Read More
A while back we wrote an article for Slate about the funny (and sometimes inappropriate) titles scientists give their papers. Since then, our readers have flooded our email with more examples, many of which were from their own papers. Here are a few of our favorite fun, clever, and just plain odd paper titles… enjoy!
We know that methane from cow farts is a greenhouse gas and a contributor to global warming. But how about farts from camelids (camels, llamas, and alpacas), which have a similar type of digestive system? In this study, the researchers set out to measure methane emission by camelids. To do so, they built “respiration chambers” for the animals (5 alpacas, 6 llamas, and 5 camels) — basically, sealed rooms that allowed the scientists to control and measure the air coming in and out. Then they waited for the camels/llamas/alpacas to fart. Turns out that camelids produce less methane overall than cows, probably due to their lower food intake. Still, the next time you’re feeling bad about your job, just be glad it doesn’t involve setting up camel fart chambers.
“Methane emissions from ruminant livestock have been intensively studied in order to reduce contribution to the greenhouse effect. Ruminants were found to produce more enteric methane than other mammalian herbivores. As camelids share some features of their digestive anatomy and physiology with ruminants, it has been proposed that they produce similar amounts of methane per unit of body mass. This is of special relevance for countrywide greenhouse gas budgets of countries that harbor large populations of camelids like Australia. However, hardly any quantitative methane emission measurements have been performed in camelids. In order to fill this gap, we carried out respiration chamber measurements with three camelid species (Vicugna pacos, Lama glama, Camelus bactrianus; n = 16 in total), all kept on a diet consisting of food produced from alfalfa only. Read More
Americans aren’t exactly known for our knowledge of history (or geography, for that matter). But we should at least know our own presidents, right? Enter these researchers, who used an online survey to measure how well people can distinguish real US presidents from others with well-known or presidential-sounding names. They found that, while people were actually able to recognize 88% of US presidents by name (the exceptions including lesser known presidents like Franklin Pierce and Chester Arthur), they were also likely to incorrectly identify several non-presidents, including Alexander Hamilton and Benjamin Franklin. Of course, the researchers point out that the study was performed before the popularity of the Broadway musical “Hamilton”, which might make people more aware of Alexander Hamilton’s place in history. Maybe for the sake of public education, the next hit musical should be “Pierce”?
“Studies over the past 40 years have shown that Americans can recall about half the U.S. presidents. Do people know the presidents even though they are unable to access them for recall? We investigated this question using the powerful cues of a recognition test. Specifically, we tested the ability of 326 online subjects to recognize U.S. presidents when presented with their full names among various types of lures. Read More
If you had to guess, you’d probably say that people who watch a lot of pornography are less likely to be religious. And you’d be right — to a point. But according to this study, which looked at the connection between porn viewing and later religiosity, there actually appeared to be a more complicated relationship between porn and religious sentiments. More specifically, people who watched no porn were likely to be religious, and religious levels declined with more frequent porn use up to “once a week.” But as viewing got more frequent — up to “once a day or more” — religiosity actually went back up. This just might be the best use of our “Holy correlation, Batman!” blog post category to date!
Does Viewing Pornography Diminish Religiosity Over Time? Evidence From Two-Wave Panel Data.
“Research consistently shows a negative association between religiosity and viewing pornography. While scholars typically assume that greater religiosity leads to less frequent pornography use, none have empirically examined whether the reverse could be true: that greater pornography use may lead to lower levels of religiosity over time. I tested for this possibility using two waves of the nationally representative Portraits of American Life Study (PALS). Persons who viewed pornography at all at Wave 1 reported more religious doubt, lower religious salience, and lower prayer frequency at Wave 2 compared to those who never viewed porn. Considering the effect of porn-viewing frequency, viewing porn more often at Wave 1 corresponded to increases in religious doubt and declining religious salience at Wave 2. Read More
In the 1980s, a man named Justin Schmidt invented the Schmidt pain index, which measured the painfulness of stings from 78 species of insects on a scale of 0 to 4 (the only stings that rated 4 were the bullet ant and the tarantula hawk). Of course, pain is subjective, so Schmidt rated all of the stings himself. In that tradition, the author of this study hypothesized that the pain level of a sting also depends on its location on the body. He tested this hypothesis by — you guessed it — getting stung. A lot. Turns out that the most painful location for being stung by a bee is on the nostril, followed by the lip and the penis. Yup, the penis.
“The Schmidt Sting Pain Index rates the painfulness of 78 Hymenoptera species, using the honey bee as a reference point. However, the question of how sting painfulness varies depending on body location remains unanswered. This study rated the painfulness of honey bee stings over 25 body locations in one subject (the author). Read More