Zombies, Fire Drills, and Bad Decision-Making


Imagine that the dead have risen from their graves. They’ve gotten into a building you’re hiding out in. You slink down the hallway and enter what you think is a safe room.

It’s empty, and looks like a good place to hide. As you stand in the middle of the room, you look around. There’s only two doors: the one that you came through and one on the opposite side of the room. You should be able to barricade them both with furniture. But, oh no! The zombies have found the room, too. They’re shambling around both doors, with more crowding the doorway you just used, and now you have to get out. Which door do you exit through?

The less crowded one, I’m sure you’re saying. Of course, that makes the most sense. If both doors are the same distance from where you’re standing, why not use the one that’s got fewer obstacles?

Well, science has some bad news for you: You’ll probably wind up as a snack for the living dead, or at least stuck in a crowded doorway. Stress makes us do stupid things, like seek familiar routes even if they’re not the best ones. Over and over, eyewitness reports from real-life evacuations have suggested that, in emergencies, people tend to exit buildings from the main entrance that they used to enter the building, ignoring one or more emergency exits along the way. The crowding at these entryways slows evacuation times and sometimes results in injuries and even deaths.

Earlier this year, the Science Museum of London held a zombie-themed science festival called “ZombieLab.” Researchers Nikolai Bode and Edward Codling, from the University of Essex, took advantage of the event to look at the decisions people make in emergencies. They set up a computer simulation of a room evacuation similar to what I described above. One hundred and eighty-five museum guests took control of a computer person in a virtual environment filled with 80 virtual zombies.

At the start of the experiment, the participants just had to move their person from the hallway and into the central room. Next, they had to move back out again, through one of two doors, to where they started in the hall. During this second part, the researchers presented the visitors with a few different conditions. Some just had to simply exit the room. Others were encouraged to beat the fastest exit time. Others were presented with a crowd of zombies split unevenly between the two exits. A last group had to deal with the crowed exits while trying to beat the best time.

In the normal exit scenario and when they were trying to set the best time, the museum visitors split evenly between the two exit routes and showed no clear preference for one or the other. Faced with zombie-crowded exits, though, the visitors started to show some bias for the doorway they had come through, even if it was more crowded. Presented with the zombie obstacles alone, some of the visitors went for they door they came through, and then changed their mind when they realized how crowded the doorway was. With the added pressure of the time clock, fewer people changed their mind and stuck with trying to get out that exit, even though it was the slowest route.

Bode and Codling’s results fit with what other researchers have found in theoretical models and real-life evacuations. Under stress, people make irrational decisions. Here, the museum visitors under pressure to exit quickly were more likely to stick to the route they knew even if it wound up taking them longer to get out, and were less likely to change their mind and adapt to the situation.

In a real-world situation, the researchers say, their results suggest some strategies for minimizing risks during stressful evacuations. One idea they offer is having people in large, crowded buildings enter from several different locations. If they have to get out quickly, and their preference for the way they came in holds up, they’ll spread out to different routes and avoid overcrowding any one exit.

It’s worth mentioning that the idea that the other virtual characters in the room were zombies was just meant to fit the experiment in with the theme of the festival and keep participants blind to the purpose of the experiment. In the simulation, the zombies didn’t attack participants or pose any danger, but simply blocked the doorways. The study participants didn’t have to treat them as a threat, so they focused on choosing one door or the other without worrying about getting their brains eaten. I wonder if, or how, the results would differ if the “zombies” acted more like zombies, and how decision-making in an evacuation is affected if there are obstacles at exits that pose active threats.

More Details Emerge About 'Oumuamua, Earth's First-Recorded Interstellar Visitor

In October, scientists using the University of Hawaii's Pan-STARRS 1 telescope sighted something extraordinary: Earth's first confirmed interstellar visitor. Originally called A/2017 U1, the once-mysterious object has a new name—'Oumuamua, according to Scientific American—and researchers continue to learn more about its physical properties. Now, a team from the University of Hawaii's Institute of Astronomy has published a detailed report of what they know so far in Nature.

Fittingly, "'Oumuamua" is Hawaiian for "a messenger from afar arriving first." 'Oumuamua's astronomical designation is 1I/2017 U1. The "I" in 1I/2017 stands for "interstellar." Until now, objects similar to 'Oumuamua were always given "C" and "A" names, which stand for either comet or asteroid. New observations have researchers concluding that 'Oumuamua is unusual for more than its far-flung origins.

It's a cigar-shaped object 10 times longer than it is wide, stretching to a half-mile long. It's also reddish in color, and is similar in some ways to some asteroids in our solar system, the BBC reports. But it's much faster, zipping through our system, and has a totally different orbit from any of those objects.

After initial indecision about whether the object was a comet or an asteroid, the researchers now believe it's an asteroid. Long ago, it might have hurtled from an unknown star system into our own.

'Oumuamua may provide astronomers with new insights into how stars and planets form. The 750,000 asteroids we know of are leftovers from the formation of our solar system, trapped by the Sun's gravity. But what if, billions of years ago, other objects escaped? 'Oumuamua shows us that it's possible; perhaps there are bits and pieces from the early years of our solar system currently visiting other stars.

The researchers say it's surprising that 'Oumuamua is an asteroid instead of a comet, given that in the Oort Cloud—an icy bubble of debris thought to surround our solar system—comets are predicted to outnumber asteroids 200 to 1 and perhaps even as high as 10,000 to 1. If our own solar system is any indication, it's more likely that a comet would take off before an asteroid would.

So where did 'Oumuamua come from? That's still unknown. It's possible it could've been bumped into our realm by a close encounter with a planet—either a smaller, nearby one, or a larger, farther one. If that's the case, the planet remains to be discovered. They believe it's more likely that 'Oumuamua was ejected from a young stellar system, location unknown. And yet, they write, "the possibility that 'Oumuamua has been orbiting the galaxy for billions of years cannot be ruled out."

As for where it's headed, The Atlantic's Marina Koren notes, "It will pass the orbit of Jupiter next May, then Neptune in 2022, and Pluto in 2024. By 2025, it will coast beyond the outer edge of the Kuiper Belt, a field of icy and rocky objects."

Last month, University of Wisconsin–Madison astronomer Ralf Kotulla and scientists from UCLA and the National Optical Astronomy Observatory (NOAO) used the WIYN Telescope on Kitt Peak, Arizona, to take some of the first pictures of 'Oumuamua. You can check them out below.

Images of an interloper from beyond the solar system — an asteroid or a comet — were captured on Oct. 27 by the 3.5-meter WIYN Telescope on Kitt Peak, Ariz.
Images of 'Oumuamua—an asteroid or a comet—were captured on October 27.

U1 spotted whizzing through the Solar System in images taken with the WIYN telescope. The faint streaks are background stars. The green circles highlight the position of U1 in each image. In these images U1 is about 10 million times fainter than the faint
The green circles highlight the position of U1 in each image against faint streaks of background stars. In these images, U1 is about 10 million times fainter than the faintest visible stars.
R. Kotulla (University of Wisconsin) & WIYN/NOAO/AURA/NSF

Color image of U1, compiled from observations taken through filters centered at 4750A, 6250A, and 7500A.
Color image of U1.
R. Kotulla (University of Wisconsin) & WIYN/NOAO/AURA/NSF

Editor's note: This story has been updated.

Scientists Analyze the Moods of 90,000 Songs Based on Music and Lyrics

Based on the first few seconds of a song, the part before the vocalist starts singing, you can judge whether the lyrics are more likely to detail a night of partying or a devastating breakup. The fact that musical structures can evoke certain emotions just as strongly as words can isn't a secret. But scientists now have a better idea of which language gets paired with which chords, according to their paper published in Royal Society Open Science.

For their study, researchers from Indiana University downloaded 90,000 songs from Ultimate Guitar, a site that allows users to upload the lyrics and chords from popular songs for musicians to reference. Next, they pulled data from labMT, which crowd-sources the emotional valence (positive and negative connotations) of words. They referred to the music recognition site Gracenote to determine where and when each song was produced.

Their new method for analyzing the relationship between music and lyrics confirmed long-held knowledge: that minor chords are associated with sad feelings and major chords with happy ones. Words with a negative valence, like "pain," "die," and "lost," are all more likely to fall on the minor side of the spectrum.

But outside of major chords, the researchers found that high-valence words tend to show up in a surprising place: seventh chords. These chords contain four notes at a time and can be played in both the major and minor keys. The lyrics associated with these chords are positive all around, but their mood varies slightly depending on the type of seventh. Dominant seventh chords, for example, are often paired with terms of endearment, like "baby", or "sweet." With minor seventh chords, the words "life" and "god" are overrepresented.

Using their data, the researchers also looked at how lyric and chord valence differs between genres, regions, and eras. Sixties rock ranks highest in terms of positivity while punk and metal occupy the bottom slots. As for geography, Scandinavia (think Norwegian death metal) produces the dreariest music while songs from Asia (like K-Pop) are the happiest. So if you're looking for a song to boost your mood, we suggest digging up some Asian rock music from the 1960s, and make sure it's heavy on the seventh chords.


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