Everyone knows that pandas eat bamboo. But did you know that many of their closest relatives are carnivores? So how did the meat-eating ancestor of pandas become a vegetarian? According to this study, it may have had to do with the deactivation (technically known as “pseudogenization”) of an umami taste receptor gene. Umami is the taste that makes things like meat, soy sauce, and mushrooms extra yummy. Apparently, at some point in panda evolution, the umami receptor became non-functional. Based on how much the gene has changed, the authors calculate that this happened around the same time that pandas started eating bamboo. Whether it’s cause or effect is unclear, although the authors think the switch to bamboo may have happened before the gene was lost. Regardless, the loss of the gene reinforced the panda’s vegetarian diet because it made meat less delicious to the bears. Now if only we could make chocolate less delicious… wait, that’s a terrible idea!
“Although it belongs to the order Carnivora, the giant panda is a vegetarian with 99% of its diet being bamboo. The draft genome sequence of the giant panda shows that its umami taste receptor gene Tas1r1 is a pseudogene, prompting the proposal that the loss of the umami perception explains why the giant panda is herbivorous. Read More
Police have been using lineups for years to help eyewitnesses identify suspects in crimes. But what if you closed your eyes or it was too dark to see what was going on?
Well, according to this study, “nosewitness identification” might be the next best thing. These researchers showed subjects videos of people committing violet crimes (or neutral videos in a control condition), while at the same time asking them to sniff a sample of body odor supposedly from the perpetrator. Read More
We’ve previously discussed how having money can make you feel less pain. So it probably makes you happy too, right? Well, not so fast. This study used census data to test whether higher income is associated with happiness or sadness. Interestingly, they found that although people with money are not happier on a daily basis, they are less sad. Sound paradoxical? According to the authors, “happiness and sadness are distinct emotional states, rather than diametric opposites” — that is, just because you’re not sad doesn’t automatically mean you’re happy. So what do you do if you have money and you want to feel happy? One suggestion supported by data is to spend your money on experiences, not purchases. You’re welcome, 1%ers.
“Although extensive previous research has explored the relationship between income and happiness, no large-scale research has ever examined the relationship between income and sadness. Yet, happiness and sadness are distinct emotional states, rather than diametric opposites, and past research points to the possibility that wealth may have a greater impact on sadness than happiness. Read More
It’s been known for some time that captive dolphins can invent new vocalizations. Although such whistles may be harder for us to pronounce than names like “Flipper” or “Willy”, they nonetheless serve many of the same purposes among porpoises. That’s because dolphins make up new whistles that other dolphins then use to signal each whistle’s inventor. But what happens when dolphins meet for the first time? And what about wild dolphins–do they use “names”? Well, according to this study, the answer to both of those questions is a resounding “yes”! It turns out that when wild dolphins meet at sea, one of the first things they do is introduce themselves using their unique whistles! And so it begins…
“The bottlenose dolphin, Tursiops truncatus, is one of very few animals that, through vocal learning, can invent novel acoustic signals and copy whistles of conspecifics. Read More
Have you ever wondered why bars and parties tend to get louder and louder as the evening progresses? Is it just alcohol-fueled enthusiasm, or is there a physiological explanation? Perhaps drunk people just need to be yelled at? To test the latter idea, scientists tested participants’ hearing before and after getting drunk. And lo and behold, the results showed that consuming alcohol not only blunts the pain of a broken heart, it also deadens one’s hearing. The authors go on to suggest that some patients who complain of “cocktail party deafness” may just have had too many cocktails, and they don’t actually have a permanent hearing deficit. That sounds like a reason to celebrate–next round’s on me!
“BACKGROUND: There is very little knowledge about alcohol-induced hearing loss. Alcohol consumption and tolerance to loud noise is a well observed phenomenon as seen in the Western world where parties get noisier by the hour as the evening matures. Read More
The striking patterns of zebra stripes have puzzled evolutionary biologists for a long time. And there are a number of hypotheses out there for why zebras have evolved their signature stripes, from allowing them to hide in grass or visually confusing predators (dazzle camouflage) to helping reduce biting by insects. Here, scientists test the idea that zebra stripes actually help with cooling: “This hypothesis is based on the idea that black and white stripes would heat up differentially, thus causing differential airflow between black and white stripes and creating eddies of air that would have a cooling effect. This mechanism should work most effectively on strong, contrasting stripes, so we would predict good coverage with bold black and white striping to occur in areas in which zebra are regularly exposed to higher temperatures.”It turns out that regional temperatures, but not predator populations, can predict the intensity of the stripes found on zebras that live there (see Figure 2, below), supporting the cooling hypothesis. So there you have it: problem solved. At least for now…
“The adaptive significance of zebra stripes has thus far eluded understanding. Many explanations have been suggested, including social cohesion, thermoregulation, predation evasion and avoidance of biting flies. Read More
Although the Teenage Mutant Ninja Turtles didn’t seem to have this particular problem, it’s commonly thought that once a turtle gets stuck on its back, it’s pretty much doomed. While it’s true that turtles, like other animals with shells, can have a hard time righting themselves when flipped over, they aren’t helpless. In fact, according to these mathematicians, the domed shell of land turtles is shaped in a nearly optimal curve to help the turtle flip back over. As Donatello would say, “Turtle Power!”
“Terrestrial animals with rigid shells face imminent danger when turned upside down. A rich variety of righting strategies of beetle and turtle species have been described, but the exact role of the shell’s geometry in righting is so far unknown. Read More
As much as Facebook seems to annoy my peers, you’ve got to hand it to them–Facebook has collected a lot of data about a lot of us. And I’m pretty sure advertisers would like to believe that Facebook can use this information to understand us. But how well is that working out? How well does Facebook understand us and our personalities, compared to, say… our Facebook “friends”? Well, it turns out that all those “Likes” really do add up. Apparently, computer predictions based on participants’ clicks were more accurate at judging personalities than the participants’ actual Facebook friends. Not only that, but these computational predictions were also better at predicting things like substance use, political attitudes, and physical health. So go ahead and share this on Facebook… if you dare.
“Judging others’ personalities is an essential skill in successful social living, as personality is a key driver behind people’s interactions, behaviors, and emotions. Although accurate personality judgments stem from social-cognitive skills, developments in machine learning show that computer models can also make valid judgments. This study compares the accuracy of human and computer-based personality judgments, using a sample of 86,220 volunteers who completed a 100-item personality questionnaire. Read More
You’ve probably heard of “false confessions,” when pressure from the police and long interrogations can make someone confess to a crime they didn’t actually commit. According to this study, it’s actually not that difficult to give someone a false memory of a serious crime. Here, researchers tried to make undergraduate volunteers believe they had committed a crime when they were younger by conducting interviews in which the researchers used “suggestive memory-retrieval techniques.” They tried, for example, using false evidence (“According to your parents, you did this…”), applying social pressure (“Most people are able to retrieve lost memories if they try hard enough”), and using guided imagery to try to get the person to fill in the details of the crime. The scientists found that after several interviews, 70% of participants believed they had committed a crime (theft, assault, or assault with a weapon) in early adolescence, and they were able to give a detailed false account of this event. Be sure to check out the excerpt below for a list of other false memories that researchers have been able to implant. (Tea with Prince Charles, anyone?)
“Memory researchers long have speculated that certain tactics may lead people to recall crimes that never occurred, and thus could potentially lead to false confessions. This is the first study to provide evidence suggesting that full episodic false memories of committing crime can be generated in a controlled experimental setting. Read More
Did you know there’s an area of physics called “sloshing dynamics”? Although it more often focuses on topics like rocket fuel in tanks, these physicists have applied their knowledge of sloshing dynamics to the common problem of walking with coffee. (Which is, undoubtedly, completely unrelated to the fact that scientists apparently drink the most coffee of any profession.) To explore this problem, they conducted experiments in which people walked at different speeds with varying amounts of coffee in mugs. They found that most spills happen because we are simply moving too quickly given how full our mugs are. This greediness is not because scientists are addicted to coffee, but rather is due to “the particular range of sizes of common coffee cups, which is dictated by the convenience of carrying them and the normal consumption of coffee by humans.” In other words, if you don’t want to spill your coffee, don’t fill it so high and don’t walk so fast. You’re welcome.
“In our busy lives, almost all of us have to walk with a cup of coffee. While often we spill the drink, this familiar phenomenon has never been explored systematically. Here we report on the results of an experimental study of the conditions under which coffee spills for various walking speeds and initial liquid levels in the cup. Read More