Slime and Other Silly Projects

You know when it's the middle of a workday and you realize you're doing something really silly? Like the day I was looking at technical plans of school buses because I wanted to express the weight of a blue whale with an analogy kids could appreciate. Or the day I was out in the alley with a mixing bowl full of green slime and a hammer, and someone stopped to ask directions to the Guatemalan embassy.

If you work in a science lab, all of your days might be silly in the exact same way, at which point it becomes less funny. I used to spend all day staring at a little pile of dirt and grass roots under a lamp, and picking out the roots with tweezers. When the roots started to squirm around on the table, you knew it was time to get up and take a walk.

This week brought us three especially silly moments in science. I just hope the people in the labs were able to appreciate it.

1. Boozy Bacteria

When researchers studied the bones of 1,700-year-old Nubians and found what appeared to be tetracycline--a modern-day antibiotic--their results were met with some skepticism. After all, archaeologists hadn't yet uncovered any fourth-century pharmaceutical factories. But after further research, the scientists think they've figured out where the drugs were coming from: beer.

The Nubians brewed their beer from grain that was contaminated with strep bacteria. (Streptomyces makes tetracycline to kill off competing bacteria.) They got lots of antibiotics in their diet, starting young--even babies drank the tetracycline in their mothers' milk. The population may have recognized that drinking the beer kept them feeling healthy.

The goofiest part of the story, though, is that Emory professor George Armelagos had his students brew their own Nubian-style beer, complete with strep. It does contain tetracycline, and is described as "drinkable," but with a "greenish hue."

2. Stressing Slime Molds

Quick, how would you stress out a slime mold? (Slime molds, for the uninitiated, are single-celled organisms that sometimes come together en masse to form alarming, bright-yellow blobs and ooze across the forest floor like mobile toxic waste slicks.)

In their multi-celled form, slime molds are able to do some low-level problem solving. Researchers tested how well slime molds made decisions--choosing between foods of different concentrations--when they were stressed. So how did they stress the blobs? Shining a strong light on them worked, as did starving them.

The result was that the slime molds made hastier, and worse, decisions when stressed. Like humans, they have a hard time thinking when they're hungry.

3. Awkward Avatars

Over in the UK, some mostly-male researchers were wondering (perhaps as a result of personal experience) what kinds of dance moves women find most attractive. But you can't just ask women to watch men dance and rate them, because there could be other factors at work. A mediocre dancer might get high scores just for being good-looking. Or perhaps the "best dancer in the world" has "an awful haircut or something like that," as the lead researcher speculates wistfully.

So the scientists took inspiration from James Cameron and asked 19 guys to dance to a beat while wearing motion-capture markers. Then they transformed each dancer into a purple avatar that strongly resembles one of those bendable wooden drawing dummies.

Women were asked to watch the videos and rate the bopping androids on their dancing skills. (This guy above did not fare well; you can watch a video of his "I'm-sowing-a-field" dance, as well as a more successful dancer, here.) Researchers concluded that a few factors make a dance really successful. Moving your head and trunk around a lot is good. Also, mysteriously, "speed of movements of the right knee." Take note, guys.

To follow up, the researchers are wondering whether good dancing is an "honest signal"--that's an evolutionary term for a feature that broadcasts how fit you are. It applies to lots of male birds whose flashy feathers (or, often, dance routines) tell females they're strong and healthy. I only hope there will be videos to go with that experiment, too.

Avatar image: Northumbria University