Four articles this month, one on how behavior in robots can “evolve”, one on a new way of using stem cells, one on a controversial device to disperse teenaged loiterers in the U.K. and a last one on the creation of a material blacker than any previously known.

In the first article, researchers at the Swiss Federal Institute of Technology have created learning robots outfitted with light sensors, light rings and a neural circuitry of 30 “genes” that together determine their behavior. These robots were then placed in a specially designed habitat with designated areas containing either “food” or “poison” that charged or drained their batteries respectively. The “genes” from the survivors of each round, together with some randomness to simulate mutation, were recombined to form a new generation of robots that were again set loose in the habitat. By the 50th generation, some of the robots had evolved the ability to communicate with each other, lighting up to alert other robots to the presence of food or poison and even learned to cheat by signaling food where there is really poison and quietly “eating” the food by itself.

Experiments like this aren’t new in virtual form, but this is first example I’ve read of doing this in a physical space with robots instead of in a purely software simulation. It’s not too surprising that this experiment worked since it pretty much attempts to replicate in physical form what has already been done virtually. Still, those smart little robots would make for a great toy. Which geek wouldn’t want to be the lord and master of your private colony of slowly-learning subjects? Be mindful however of the lesson taught in George R.R. Martin’s Sandkings.

Meanwhile scientists in Finland managed to replace a patient’s upper jaw with a bone transplant cultivated from stem cells. This is pretty much what has always been promised by stem cell advocates but the cool part is that the stem cells came from the patient’s own fatty tissues and were grown in the patient’s abdomen on a scaffold for nine months. Then it was removed and attached to the patient’s skull bones with screws and microsurgery to connect the veins and arteries. Since the new jaw was grown from the patient’s own stem cells, there’s no chance of it being rejected and how many people can claim that they had a replacement jaw growing in their belly for nine months?

Next, it appears that shopkeepers in the United Kingdom have been using a new device that uses ultrasonics to deter youths from loitering around their premises since late last year. Called the “Mosquito”, the device continuously emits a high-pitched whine that has been described as being extremely annoying and even painful by those hearing it. Of course, that’s no help if it turns everyone away from the shop, so the most interesting thing about the device is that the sound it emits is set at a frequency that can only be heard by those under the age of 25. This is because the ear’s ability to hear high frequency noises diminishes with age.

Shopkeepers appear to love the device since it does keep troublesome teenagers from loitering nearby, but there have been plenty of complaints as well. A particular point of controversy is that it affects young children and babies as well, and of course, it doesn’t discriminate between those who misbehave from those who do not. Despite calls for it to be banned, it’s still legal in the U.K. but so far I haven’t heard of it being used in other countries.

Finally, scientists at the Rensselaer Polytechnic Institute and Rice University have created a new material that they claim is blacker than any other. The material is made from vertically-aligned carbon nanotubes (it there anything these things can’t do?) and has a reflective index of only 0.045 percent, meaning that it reflects very, very little of the light that falls on it. As expected, something like this has many potential uses. The efficiency of solar energy panels for example, depends heavily how much of the energy of the light that falls on it can be absorbed. The researchers have also submitted a claim to the Guinness Book of World Records for making the blackest black yet.