Researchers working on biomimicry have produced the first structural color change in an animal by influencing evolution: They've changed the color of the butterfly Bicyclus anynana from brown to violet - and needed only six generations of selection to do it.

Little is known about how structural colors in nature evolved, although researchers have studied such mechanisms extensively in recent years. Most attempts at biomimicry involve finding a desirable outcome in nature and simply trying to copy it in the laboratory.

The discovery published in Proceedings of the National Academy of Sciences may have implications for physicists and engineers trying to use evolutionary principles in the design of new materials and devices.

Physicists have identified a mechanism that may help explain Zipf's law – a unique pattern of behavior found in disparate systems, including complex biological ones. Their mathematical models demonstrate how Zipf's law naturally arises when a sufficient number of units react to a hidden variable in a system.

Oxazepam, a drug that is commonly used to treat insomnia and anxiety in humans, has been shown to reduce mortality rates in fish when it gets into natural water supplies. 

For their study, researchers retrieved two-year-old Eurasian perch from a lake in Sweden and randomly exposed them to high and low concentrations of Oxazepam, a benzodiazepine which is commonly used to treat anxiety and insomnia in humans and regularly contaminates surface waters via treated wastewater effluent. The researchers have previously found that the drug can increase the activity and boldness of Eurasian perch. 

A recent study conducted by Mayo Clinic researchers recommends laparoscopic cholecystectomies (surgical removal of the gallbladder) for pediatric patients suffering from gallstones and other gallbladder diseases. 

A cholecystectomy is a surgical procedure performed to remove the gallbladder, a pear-shaped organ located below the liver on the upper right side of the abdomen. The gallbladder is responsible for collecting and storing bile, which is a fluid secreted by the liver.

During a laparoscopic cholecystectomy, four incisions are made in the abdomen. Then, a small video camera and other special tools are used to remove the gallbladder.

For years, researchers at MIT and Harvard University have been working on origami robots — reconfigurable machines that can fold themselves into arbitrary shapes.

In Science, they report their latest milestone, which is a robot made almost entirely from parts produced by a laser cutter that folds itself up and crawls away as soon as batteries are attached to it. 

The robot is built from five layers of materials, all cut according to digital specifications by a laser cutter. The middle layer is copper, etched into an intricate network of electrical leads. It's sandwiched between two structural layers of paper; the outer layers are composed of a shape-memory polymer that folds when heated.

Throughout the 1990s, biofuels were the environmental rage. Everyone from Vice-President Al Gore to Greenpeace touted them as the replacement for fossil fuels. The future belonged to such renewable energy.

Benefited by a Republican Congress that loved science, President George W. Bush mandated and subsidized biofuel energy, but only the final product. The product used to make this ethanol was left up to growers. 

As a quantum state collapses from a quantum superposition to a classical state or a different superposition, it will follow a path known as a quantum trajectory. For each start and end state there is an optimal or "most likely" path, but it is not as easy to predict the path or track it experimentally as a straight-line between two points would be in our everyday, classical world.

Your stress levels may be another thing you can blame on your mother. Scientists investigating pregnancies in four generations of rats show that inherited epigenetic effects of stress could affect pregnancies for generations. 

The researchers believe that these changes are due to epigenetics - the arrangement and expression of our genes. In most cases this refers to DNA methylation of the nucleotide base pairs. In this study the researchers believe the epigenetic changes are due to microRNA (miRNA) - non-coding RNA molecules that play a role in regulating gene expression.

Slippery as an eel may be a popular phrase but it turns out they are a lot easier to catch when marine vessels make noise nearby.

In a Global Change Biology paper, researchers from the Universities of Exeter and Bristol found that fish exposed to playback of ship noise lose crucial responses to predator threats - European eels (anguilla anguilla)were 50% less likely to respond to an ambush from a predator, while those that did had 25% slower reaction times.

Those that were pursued by a predator were caught more than twice as quickly when exposed to the noise.