Science News

We’re nice to our families. From an evolutionary perspective, that makes sense. But what makes us deal fairly with strangers? One theory holds that the development of large societies necessitated the creation of fairness, through institutions such as markets and religion that extend fairness to a so-called ‘anonymous other.’

In a study published in the journal Science , anthropologists and economists around the world spent 15 years studying communities of 2,000 to 10,000 individuals with highly variable social systems.

In this era of Facebook, Twitter and the iPhone, it is easy to take for granted our ability to connect to the world. Yet communication is most critical precisely at those times when the communications infrastructure is lost. In Haiti, for example, satellite phones provided by aid agencies were the primary method of communication for days following the tragic earthquake earlier this year. But even ordinary events such as a power outage could cripple the cell phone infrastructure, turning our primary emergency contact devices into glowing paperweights.

In situations such as these, an increasingly attractive option is to create an “ad-hoc” network. Such networks form on their own wherever specially programmed mobile phones or other communications devices are in range of one another. Each device in the network acts as both transmitter and receiver and, crucially, as a relay point for all the other devices nearby. Devices that are out of range can communicate if those between them are willing to help--passing messages from one to the next like water in a bucket brigade. In other words, each node in the network functions as both a communicator for its own messages and infrastructure for the messages of others.

NEW YORK - For the average United States' city or 'burb dweller, firsthand evidence of climate change is rare. Hunters and anglers see it every day.

By Janet Fang

Short sequences of RNA that can effectively turn off specific genes have for the first time been used to treat skin cancer in people.

The technique, called RNA interference (RNAi), gained its inventors a Nobel Prize in 2006, but researchers have struggled to get it to the clinic, partly because of problems in getting the molecules to their target.

Now, Mark Davis from the California Institute of Technology in Pasadena and his colleagues have found a way to deliver particles containing such sequences to patients with the skin cancer melanoma. [More]