Knoxville, TN, USA. Mate choice, competition, and the variety of resources available are the key factors influencing how a species evolves into separate species.

A new mathematical model that integrates all three factors to reveal the dynamics at play, in a process called sympatric speciation, appears in the Journal of Evolutionary Biology.

Washington, DC, USA. State, national, and local policymakers should elevate K-12 science education to the same importance as reading and mathematics, says the National Research Council, recommending ways to improve K-12 education in science, technology, engineering, and mathematics.

The report grew from a request by Rep. Frank Wolf (R-Va.) for the National Science Foundation (NSF) to identify highly successful K-12 schools and programs in STEM fields.

New York, NY, USA. Understanding the complex process that leads to the flow of neurotransmitters between brain neurons has taken a step forward with new findings in the journals Nature Neuroscience and Neuron.

Both studies focus on synaptic vesicles, which are bubble-like structures that store neurotransmitters within a bi-layer of fatty membranes at the synaptic junction.

Cambridge, MA, USA. Scientists measured the density of a single cell using a procedure that has existed for 2,000 years when Archimedes found a way to determine the density (and purity) of a king's gold crown by measuring its mass in two different fluids.

Accurate measurements open a new window on cell biology, encouraging biophysical insight into fundamental cellular processes — such as adaptations for survival — and might also be useful for identifying diseased cells.

Atlanta, GA, USA. Charles Darwin's hypothesis — that the struggle for existence is stronger between more closely related species than those distantly related — has received the strongest direct experimental evidence yet to support its validity.

Ecologists have generally accepted Darwin's premise, but the new research provides more greater specificity for predictors of the outcomes of competitive interactions in ecological communities.