This silverfish didn’t fool the army ants. But many do.
The silverfish Malayatelura ponerophila is a kleptomaniac parasite that lives amongst the fierce army ants of southeast Asia, hanging out in the insect’s mobile colonies and living off the food they bring home. But how does it survive as a full-time impostor?
A study just accepted for publication in the journal BMC Evolution shows that these furtive freeloaders avoid detection by rubbing themselves all over immature ants called callows, “adolescent” ants which recently emerged from their larval stage. This gives the silverfish a coating of chemicals, called cuticular hydrocarbons (or CHCs), that the near-blind ants use to recognize nestmates in the dark. It is a dangerous way to live; army ants have keen senses and are usually adept at recognizing intruders, even expelling or killing fellow Leptogenys distinguenda if they smell like they’re from a different colony.
Several years ago, researchers in (you guessed it) Japan put together a reasonable facsimile of the human vocal apparatus in an attempt to help hearing-impairing people learn to better modulate their voices. The details of how this process works can be perused here, but we’d just like to treat you to a trailer of this creepy little puppy in action, moaning the nursery rhyme “Kagome, Kagome,” before some major film studio options it for a B-grade horror flick. Titles, anyone?
Have you ever wondered why woodpeckers don’t pass out after scrounging a meal from a tree? Their little brains, after all, undergo decelerations of 1200g as they bang their beaks against the wood–over ten times the force needed to give a human a concussion. Now scientists are learning how to harness the woodpecker’s special abilities not to prevent headaches, but to safeguard our gadgets.
Researchers at the University of California, Berkeley, analyzed CT scans and video footage of the golden-fronted woodpecker (Melanerpes aurifons) to design better shock absorbers. They found that woodpeckers have four traits that ease their noggins: fluid between the skull and brain, a beak that is slightly elastic, a section of soft skull bone, and a bone called the hyoid, or lingual bone, which is also somewhat elastic.
The scientists then constructed a woodpecker-inspired shock-absorbing system around a circuit using materials that approximated the bird’s four absorbers. For example, rubber represented the supportive and slightly-elastic nature of the hyoid bone, while aluminum mimicked the brain-skull fluid. With the circuit securely surrounded, they stuffed it inside a bullet and fired the bullet at an aluminum wall using an air gun.
In pursuit of a glorious future in which robots can outrun humans (what could possibly go wrong?), researcher Ryuma Niiyama has unveiled Athlete, a bot that’s intended to sprint.
The bipedal robot’s upper legs are modeled on the human musculoskeletal system, while the lower legs are fashioned from the spring-like blades that amputee runners use (and use so effectively that some have called the blades an unfair advantage).
Erico Guizzo of IEEE Spectrum explains:
Each leg has seven sets of artificial muscles. The sets, each with one to six pneumatic actuators, correspond to muscles in the human body — gluteus maximus, adductor, hamstring, and so forth…. The researchers are now teaching Athlete to run. They programmed the robot to activate its artificial muscles with the same timing and pattern of a person’s muscles during running.
Niiyama described his bot at the IEEE conference on humanoid robots last week, and has published a paper (pdf) on the project in the journal Industrial Robot. The challenge is to get all those artificial muscles working in sequence as the bot bounds across the landscape.
It’s a big challenge. So far, Athlete can take only three to five steps before tumbling to the ground. Still that’s pretty impressive compared to a hopping prototype from 2007 (seen in the video below), which took one great leap for robotics and promptly fell down. Humans, maybe you don’t need to run for your lives just yet.
Discoblog: Brain Surgery Enables Woman to Run 100-Mile Races
80beats: Ostriches Are Endurance Runners, Thanks to the Spring in Their Steps
80beats: Running by the Books: Math for the Marathoner
80beats: No Shoes, No Problem? Barefoot Runners Put Far Less Stress on Their Feet
80beats: Scientist Smackdown: Are a Sprinter’s Prostethic Legs an Unfair Advantage?
Video: Ryuma Niiyama
Geckos, like cats and buttered toast, can naturally turn themselves around in midair. Cats are able to right themselves because they are flexible and can twist their bodies around. The gecko, on the other hand, uses its large tail’s inertia to twist its body around to the correct orientation, explains Cosmic Log:
Within about a tenth of a second, the geckos flipped their tails around to induce body rotation. Then they spread out their tails as well as their feet into a “belly-down skydiving posture” position to stabilize the fall. All of the geckos that used their tails in this way landed on their feet, even in wind-tunnel tests–while none of the tailless geckos could do the same trick.
Hit the jump for a video of the gecko-bot in action.
These researchers want to take their butterflies to the bank. They’ve found a way to mimic the nanostructures responsible for giving butterfly wings their colors, and they think butterfly-inspired money designs might hinder counterfeiters.
“We still need to refine our system, but in future we could see structures based on butterflies wings shining from a £10 note or even our passports,” said Mathias Kolle in a university press release. Kolle researched the butterfly’s wing structure with Ullrich Steiner and Jeremy Baumberg at the University of Cambridge.
Butterfly wings don’t use traditional pigment for their flair. Instead, they rely on the way light bounces off tiny multilayer structures on their wings. These micro- and nanostructures come in a variety of shapes (see the “egg carton-like” scanning electron microscope picture below), and scientists have long had inklings as to how different structures result in different colors. But Kolle and colleagues have gone one step further, managing the elusive task of copying this craft.