In their study,A first-principles model of early evolution: Emergence of gene families, species, and preferred protein folds, Shakhnovich et al present a new model of early biological evolution – the first that directly relates the fitness of a population of evolving model organisms to the properties of their proteins.

Key to understanding biological evolution is an important, but elusive, connection, known as the genotype-phenotype relationship, which translates the survival of entire organisms into microscopic selection for particular advantageous genes, or protein sequences.

A Cornell study of genome sequences in African-Americans, European-Americans and Chinese suggests that natural selection has caused as much as 10 percent of the human genome to change in some populations in the last 15,000 to 100,000 years, when people began migrating from Africa.

The study looked for areas where most members of a population showed the same genetic changes. For example, the researchers found evidence of recent selection on skin pigmentation genes, providing the genetic data to support theories proposed by anthropologists for decades that as anatomically modern humans migrated out of Africa and experienced different climates and sunlight levels, their skin colors adapted to the new environments.

Using plastics to harvest the energy of the sun just got a significant boost in efficiency thanks to a discovery made at the Center for Polymers and Organic Solids at the University of California, Santa Barbara.

Nobel laureate Alan Heeger, professor of physics at UC Santa Barbara, worked with Kwanghee Lee of Korea and a team of other scientists to create a new “tandem” organic solar cell with increased efficiency. The discovery marks a step forward in materials science.

A team of researchers at Umeå University in Sweden have discovered a unique mechanism by which the same signal molecule determines the formation of the both the lens of the eye and the olfactory cells of the nose.

Smell and sight are two sensory systems that are crucial to our ability to perceive the world around us. The ability to sense smells is established by the development of the olfactory mucous membrane. The ability to see is similarly dependent on the formation of the lens in the eyes.

Estrogen, which binds estrogen receptor alpha (ER-alpha), is a risk factor for breast cancer development. However, one-third of new breast cancers lack detectable ER-alpha. These ER-alpha–negative cancers are more aggressive and have a worse prognosis than do ER-alpha–positive breast cancers, and have been thought to be estrogen independent.

In a new study, Joyce Slingerland and colleagues from the University of Miami shed further light on the mechanisms regulating ER-alpha expression levels during breast cancer.

That title alone should get this article on the front page of technology papers everywhere, but the comparisons are valid.

Though people feel they have rich visual experiences, researchers have found that the average person is only aware of about four things at a time. This short term capability varies from person to person but an individual’s capacity for short-term memory is a strong predictor of IQ and scholastic achievement. People with high IQs can think about more things at once.

For example, a four-gigabyte iPhone, the popular new Apple cell phone, might be able to hold about 1,000 four-minute songs, but far fewer if the songs were all 20 minutes in length, explained University of Oregon psychology professors Edward Awh and Edward Vogel.