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Spider Assassin and Other Costume Ideas

Still don't know what you're going to be for Halloween? Don't worry! Inspired by this week's scientific findings, I'm here to help.




Motion-capture ostrich

This ostrich is all ready to go door-to-door with its snazzy costume of reflective dots. Its outfit was created by a team of American and Australian scientists who wanted to analyze what makes ostriches such efficient runners. They found that the birds' secret is very springy tendons that allow them to store and release a lot more elastic energy than humans can.

(Another unstated conclusion of this paper is that you should never try to train an ostrich. Researchers note that after they hand-reared five ostriches and spent eight months training them 3-4 times a week, only "two animals were amenable to the procedures required for full three-dimensional gait analysis.")

If you are already an ostrich, this costume will require less work to prepare. But you will need help from someone with hands.


Spider assassin

Hate spiders? Dress up as Stenolemus bituberus, the assassin bug. These wily insects sneak onto spider webs and wiggle the threads to get the spiders' attention. When spiders come to investigate, the assassin bugs attack. Researchers recorded the web vibrations made by assassin bugs and compared them to the vibrations made by other things that might fall into a web: aphids, fruit flies, falling leaves, or male spiders that come a-courting. ("Recordings of courting males continued until the male copulated with the female.")

They found that the vibrations made by an assassin bug tapping on a spider's web were very similar to the vibrations made by a trapped meal (a fly or an aphid). The spider's response to the vibrations was the same, too: it snapped to attention and cautiously went to investigate. Just like all those candy-carrying folks will when you tap-tap-tap on their door in this awesome costume.



Implantable LEDs

Obviously, a costume incorporating implantable LEDs will make you the coolest kid on the block. This technology is meant to be used for medical devices--a light-up display under a person's skin could let doctors know whether something's working right. But it could also make sweet glowing tattoos. You'll just need to have some minor surgery first.

Actually, this might be a better one to keep in mind for next year.


Images: University of Western Australia/Jonas Rubenson; www.maine.gov; Nature Materials/John Roberts

Severe Pretend Storm Warning

The newly constructed Institute for Business and Home Safety (IBHS) Research Center is, disappointingly, not in Kansas. But it is able, within its six-story walls, to simulate a tornado. Or a hailstorm. Or a wildfire.

The insurance industry spent $40 million to build this giant facility in South Carolina. It contains a turntable that can hold 9 full-size houses, built to various safety standards, and subject them to almost any kind of severe weather condition. A water tank larger than an Olympic swimming pool makes the rain, which falls at up to 8 inches an hour. One hundred and five fans, each five and a half feet across, generate winds up to 140 mph. Burning embers can be made to fly through the air.

In this video, you can see a house go down like a pile of toothpicks in a simulated windstorm. Next to it, a specially fortified house sheds a few shingles but looks otherwise unbothered. Eventually, the IBHS plans to throw airplanes and tractor trailers into the mix. "There are all kinds of things we can fit in there," executive Julie Rochman says (with, one imagines, barely restrained glee).

It's a testament to how much money they lose in major disasters that the insurance industry is willing to spend $100,000 for just one hurricane simulation. The Wall Street Journal says that in the first half of 2010, insured catastrophic losses cost the industry $7.9 billion. And in a warming world, extreme weather events are expected to be more frequent. This kind of research will keep us at least a little safer.

In unrelated news, Paul, the octopus who was famous for predicting World Cup winners, died today. Farewell, inkfish friend!


Photo: DisasterSafety.org

What to Say to Climate Change Deniers

According to a New York Times editorial this week, out of around 20 Republican senatorial candidates "with a serious chance of winning next month," only one believes that humans are responsible for climate change.

(If this doesn't bother you, go ahead and move along. But know that you're making me sad.)

If it worries you that soon there will be even more people in the senate who believe that climate science is "malarkey," here is a handy toolkit of responses you can give to climate change deniers. Playing the role of the deniers will be actual commenters who posted replies to the Times editorial. (In the interest of brevity, most comments have been abridged.)
Global warming based upon man-made CO2 is a theory nothing more. Dems like any reason to raise taxes... [recommended 177 times]
Global warming is a theory, yes. So is gravity. In science, unlike in the rest of the English language, a theory doesn't just mean a guess. It means a principle that's supported by repeated testing and hasn't been disproven. I'm still pretty sure I know what will happen if I fall off a roof.
Those of us who choose to say - show us the data are vilified by the intelligentsia - the same group who mocked us over and over again throughout history for believing that the scientific method (not the preconceived notion method) is valid. [recommended 134 times]
OK! Here are some data.
- Thanks to fossil fuels, we've been putting CO2 into the atmosphere since the Industrial Revolution. Since the 1950s, we've been able to watch carbon dioxide in the atmosphere steadily increasing.
- There hasn't been this much CO2 in the atmosphere at any point over the past 800,000 years.
- The average global temperature has also been steadily rising during the past 100 years. The Intergovernmental Panel on Climate Change calls this change "incontrovertible."
- So has sea level.
- Meanwhile, Arctic sea ice is melting.
- And glaciers are retreating.
- These changes cannot be accounted for by a change in solar activity.
The climate is always changing over time. [recommended 8 times]
In the distant past, the earth has seen both prolonged ice ages and toasty, dinosaur-rific periods. But these temperature swings were not random. Scientists have connected historical temperature changes to shifts in the earth's orbit, changes in solar activity, and giant volcanoes. Over the past 2,000 years, temperatures have been pretty stable. This is the norm for an "interglacial" period, which is what we're in now. Evidence suggests that no point in the last 1,100 years has been as warm as the present day.

Additionally, we know that CO2 in the atmosphere warms the earth--the greenhouse effect is the reason we're able to live on the planet comfortably in the first place.

Is it possible that a mysterious geophysical phenomenon is causing global temperatures to increase in exactly the way computer models would predict based on the extra CO2 in the atmosphere and, simultaneously, the greenhouse effect has ceased to function normally? Sure. But if I walk outside right now and fall on my face, I'm not blaming invisible malicious elves. I'm blaming gravity.
Like many (most?) other people, global warming, man-made or otherwise is actually a positive for me. [recommended 4 times]
It must be nice for you not to care about mass extinctions. But you should know that global climate change, while increasing the temperature overall, will not affect every place in the same way. Floods, droughts, tropical storms, or heavy precipitation might be more frequent where you live. (Don't worry; Republican senator Jim DeMint is confused by this too.)
This is just a ruse by China, Russia, and other countries to economically weaken the West. [recommended 14 times]
Well, I admit I hadn't thought of that.

Is Your Dog an Optimist or a Pessimist?



It might not be right to give labels like "optimist" or "pessimist" to animals whose perspective is so narrow that every time you feed them, they seem to think they've never eaten before. But researchers in the UK say that a dog's underlying attitude, or cognitive bias, makes it assume better or worse outcomes. And that attitude affects its behavior.

The researchers were specifically interested in anxious behaviors that dogs show when their owners leave. They call this "separation related behavior," or SRB, and it can include howling, whining, destroying things, or "toileting." (Hobbes, the morose black-and-white fellow above, has been known to eat an entire roll of toilet paper when left alone. But I digress.)

To measure dogs' separation related behaviors, the researchers used 24 dogs in shelters. On one day, someone would spend 20 minutes taking the dog to a separate room and hanging out one-on-one. The next day, they'd bring the dog back to the room, play for 10 minutes, and then leave. A camera recorded the dogs for the next five minutes, and their anxious behaviors were tallied to give an overall SRB score. (This test also predicts how a dog will behave in its new home--and shows that a shelter dog will latch on to a person in the blink of an eye.)

A couple days later, the researchers returned to test the dogs' underlying attitudes. In a small room, one person would hold the dog behind a screen while another person set a food bowl all the way to one side of the room. Then they brought the dog out and let it investigate. The dogs quickly learned the trick: if the bowl was against one wall, it held a scoop of food; against the other wall, it was empty. Soon, if the dog saw the bowl against the good wall, it would leap for the food. But if the bowl was on the bad wall, some dogs would amble over slowly to give it a sniff; others, researchers Emily Blackwell says, would "give us a big sigh" and lie down.

Then came the real test: the dog came out from behind the screen to see the bowl in the middle of the room. Sometimes it was closer to the good wall, sometimes closer to the bad wall, and sometimes smack in the center. The researchers wanted to know if the dogs would sprint to the bowl to check for food, wander over slowly, or not even bother. This was the "cognitive bias": did the dogs assume a happy outcome, or a hungry one?

In general, the dogs were slower to get to the food bowl (which was empty) the closer it was to the no-food wall. But when the bowl was in the exact center of the room, some dogs were distinctly slower--that is, more "pessimistic"--than others. And sure enough, these were the dogs with the worst separation behaviors.

Though the researchers point out that "the conscious experience of such a state cannot be known for sure"--who knows what goes on in a dog's head?--they do think that dogs with bad separation behaviors have an underlying negative bias. It could be a genetic component of a dog's personality (animality?), or maybe something they've learned. Dogs learn quickly, and a dog who's in a shelter has already been handed the empty bowl by life.

An anxious shelter dog can still, of course, be an eager and cuddly addition to a home. You just might want to keep him away from the toilet paper.


Stand and Walk!



I promise this video will brighten your day. A woman named Amanda Boxtel, who's been a paraplegic for 18 years, straps on a pair of robotic legs and goes for a walk. She couldn't possibly smile any harder.

The eLEGS are made by Berkeley Bionics. After working for several years on robotic exoskeletons that help able-bodied people carry heavier loads, the group licensed that technology to Lockheed Martin to develop for the military. Now Berkeley Bionics is focusing on a different project: giving paralyzed people the power to walk.

The eLEGS are a kind of frame for the legs, attached to a backpack. To use the legs, a person straps his or her body into the frame and stands up with the help of two crutches. Sensors in the crutches tell the robotic legs when the user is trying to take a step, and the legs respond by bending in a near-normal walking motion. Batteries keep the legs going for up to six hours at a time.

The current prototypes of eLEGS can only travel in straight lines. But next year, clinical testing will begin on models that should be able to make turns. And Berkeley Bionics hopes to release eLEGS to the public by the second half of 2011. Besides giving back a degree of mobility and independence to long-paralyzed people, the legs might be therapeutic for those with more recent spinal injuries; they'll be able to keep their bodies upright and moving around, instead of settling their muscles into an all-seated lifestyle.

Though the paraplegics who've tested the system won't be entering any footraces--they can't travel much more than two miles an hour--they are thrilled just to stand up and see people at eye level. Leaving the lab to test the legs outdoors, Amanda creeps along a tree-lined path and shouts, "I'm doing it!"

Definitely less heartwarming, but also pretty cool, are these Pseudomonas bacteria. Researchers recently discovered that not all Pseudomonas scoot around in the same horizontal fashion. Some use little arm-like structures called pili to stand upright and "walk" around. Here, you can watch a video of one bacterium turning itself vertical and wandering off. Hallelujah!


Images: berkeleybionics.com, news.sciencemag.org

Genetically Modified Meat Is Coming. Should You Worry?

Are you ready for genetically modified food to hit your plate?

Trick question! You're already eating it. In 2009, 91% of the U.S. soybean crop was genetically modified, as was 85% of our corn. Soy and corn are ingredients in just about any food that has an ingredients label. Go check your cabinet if you don't believe me.

Don't be intimidated by the science. "Genetically modified" or "genetically engineered" (GM or GE for brevity's sake) just mean that extra genes were snuck into these plants' DNA. Usually, the extra genes make the plants resistant to weedkillers or infections, giving farms higher yields.

GM meat, though, is not available in the United States. Yet. The FDA recently released a mostly-positive report on a type of GM salmon called AquAdvantage. Though an advisory committee decided more time was needed to study the salmon, it seems inevitable that this fish, or something like it, will eventually reach the market. Here's a handy guide to how much this should worry you.

Should I be afraid of . . .

. . . Frankenfish? A Google search for the exact phrase "genetically modified frankenfish" returns over 97,000 results. So clearly someone is afraid of this, whatever it is. It may help to remember that just because a fish has an extra gene or two doesn't mean it has bolts coming out of its face. AquAdvantage salmon have extra genes that let them make more growth hormone than usual. As a result, they grow faster than regular fish.

. . . extra hormones in my food? Probably not. There's no evidence that your body can do anything with a fish hormone.

. . . escaped GM fish wiping out wild fish populations? Great question! Scientists definitely don't want genetically modified fish, which are raised in farms, to mingle with wild fish. This could really mess up a population of wild fish, either by bullying them out of their food or by spreading genes that are harmful in the long term. The makers of AquAdvantage are taking extensive measures to prevent this. First, they've made their salmon all female and all (in theory) sterile. And the fish are separated from waterways by several levels of physical barricades.

Still, the FDA says that up to 5% of AquAdvantage salmon might squeak through the sterilization process un-sterilized. For now, there seem to be plenty of walls and nets to hold those still-fertile fish in place. But if the fish are raised and sold all over the country, some facilities might not be as fastidious as others about sterilization or containment. And once you're talking about millions of fish, even 5% becomes a lot of salmon to worry about.

. . . natural disasters? Could a big enough flood wash all of these GM salmon out of contained areas and into open waterways? People try to design fish pens such that it would take a really rare natural disaster to cause problems. But global warming might already be increasing the frequency of natural disasters in the world--not just storms and floods, but even earthquakes and volcanoes as melting ice and rising oceans change the pressure on faults. A so-called "100-year event," which is the standard the USDA aims for, might happen more often in the future.

. . . deformed fish? Not on your plate. But in their enclosures, plenty of these fish are swimming around with hunchbacks, deformed gills, or abnormal jaws. It doesn't have to do with genetic engineering, though. It's just a fact of fish farming. At some salmon farms, 70 or 80% of fish have been found to be deformed.

This study only examined a small number of AquAdvantage fish for deformities, and concluded that the added genes aren't a problem. But the process used to sterilize the fish, which is not unusual for fish farming, does cause deformities. Out of 12 sterilized AquAdvantage fish, at least 10 had structural abnormalities.

. . . sea lice? Of course not! Unless you're a fish on a fish farm, in which case, yes. And if you're a wild salmon that has to swim past a fish farm, you might have to worry that sea lice will latch onto you and, pretty soon, wipe out your whole population.

So it's probably not worth it to concern yourself about genetically modified food. I, for one, have enough to worry about already.

Goldilocks Would Never Use Banned Substances (a quiz)

It's time to find out how well you've been following the news! This week was a big one for both space and Spain.

1. Astronomers are pretty excited about a newly discovered planet called Gliese 851. The planet orbits its star in a so-called "Goldilocks zone," which means it is:
a. in close orbit to a small planet, a medium planet, and a large planet
b. just the right size for humans to be able to walk around comfortably--unlike a huge planet whose gravity would pin us down, or a tiny planet where we'd bounce around uselessly
c. just the right temperature for liquid water to exist
d. blond, with a propensity to sit in the wrong chair

2. Speaking of outer space, congress just passed a new NASA bill. Under President Obama's plan, the space organization will do all of the following EXCEPT:
a. return to the moon by 2020
b. fly to an asteroid and/or Mars
c. fund private spaceflight
d. retire the NASA shuttles for good

3. If you live in a mid-Atlantic state, you might be currently overrun by stink bugs. What makes these triangular brown fellows such formidable opponents?
a. They have a sulfurous odor that becomes overwhelming when they're in large groups.
b. They were introduced from Asia and have no natural predators here.
c. They have a fondness for biting people's ankles and fingers.
d. They are impervious to pesticides.

4. Spanish cyclist Alberto Contador, who's won the Tour de France three times, was suspended this week over a positive test for the banned substance clenbuterol. He insists the drug came from a contaminated steak. (Though if it's true that plastic residues were also found in his blood--suggesting a blood transfusion from a plastic bag--the steak excuse is not going to get him very far.) In addition to cheating cyclists, other users of clenbuterol include all of the following EXCEPT:
a. horses
b. asthmatics
c. farmed fish
d. Hollywood types trying to lose weight
e. cheating baseball players

5. A Spanish team took home the prize at the 2K BotPrize 2010 robotics competition this week (presumably without the help of banned substances). Contest judges played against both humans and robots in a video game, and tried to guess which avatars were which. The Spanish team had the most convincing robot, with a "humanness rating" (how often it was guessed to be human) of 31.8%. For comparison, the actual humans had humanness ratings ranging from:
a. 85-95%
b. 60-90%
c. 50-85%
d. 35-80%

Answers are in the comments.