A University of Florida-led study has determined that Titanis walleri, a prehistoric 7-foot-tall flightless “terror bird,” arrived in North America from South America long before a land bridge connected the two continents.

UF paleontologist Bruce MacFadden said his team used an established geochemical technique that analyzes rare earth elements in a new application to revise the ages of terror bird fossils in Texas and Florida, the only places in North America where the species has been found.

Despite the icy cold and darkness, beneath the frozen surface of the sea in Antarctica thrives a rich and complex array of plants and animals. But what will happen to all those creatures if global warming reduces the ice-cover, as is predicted for coming decades?

UNSW marine ecologists Dr Emma Johnston and Graeme Clark have been working with the Australian Antarctic Division to survey marine communities along the striking coast of Wilkes Land, east Antarctica.

Taking a cue from the financial world, MIT researchers along with experts in industry and government have developed a list of 13 measures that engineers can use to predict how well a system -- or project -- will perform before it is even finished.

Known as leading indicators, analogous measures are regularly used by economists, investors and businesses to help predict the economy's performance.

The idea behind the new set of leading indicators is to improve the management and performance of complex programs before they are delivered, in a more predictive way than simple business metrics.

"Leading indicators can provide important insights for managers of complex programs, such as those in the aerospace industry, and can allow them to make real-ti

Carnivores are some of the widest ranging terrestrial mammals for their size, and this affects their energy intake and needs. This difference is also played out in the different hunting strategies of small and large carnivores.

Subhash Kak, Delaune Distinguished Professor of Electrical and Computer Engineering at LSU, recently resolved the twin paradox, known as one of the most enduring puzzles of modern-day physics.

First suggested by Albert Einstein more than 100 years ago, the paradox deals with the effects of time in the context of travel at near the speed of light. Einstein originally used the example of two clocks – one motionless, one in transit. He stated that, due to the laws of physics, clocks being transported near the speed of light would move more slowly than clocks that remained stationary. In more recent times, the paradox has been described using the analogy of twins.

Thanks to Buck and Axel and colleagues, most neuroscientists are aware of the precise topographical map of the mouse olfactory nerve projection in which each olfactory sensory neuron (OSN) expresses a single odorant receptor (OR), and OSNs expressing a given OR converge on a set of glomeruli in the olfactory bulb. This week, Sato et al. mapped the zebrafish axonal projection using a bacterial artificial chromosome transgene. The transgene contained a cluster of 16 OR genes, two of which (OR111–7 and OR103–1) were replaced with yellow and cyan membrane-targeted reporters. Distinct sets of OSNs were fluorescently labeled, whereas their axons targeted the same cluster of glomeruli.

A provocative new model proposed by molecular biologist John Tower of the University of Southern California may help answer an enduring scientific question: Why do women tend to live longer than men?

That tendency holds true in humans and many other mammals as well as in the much-studied fruit fly Drosophila melanogaster.

In genetic studies of Drosophila, Tower and his team have shown that genes known to increase longevity always affect male and female flies differently.

"For a long time, we only did experiments in one sex or the other, depending on what was convenient," said Tower, an associate professor of biological sciences in the USC College of Letters, Arts & Sciences who has studied the genetics of aging in Drosophila for the last two decades.

How can defense or intelligence agencies safeguard the security of top-secret data protected by a computation device the size of a single molecule?

With cryptography approaching that sobering new era, scientists in Israel are reporting development of what they term the first molecular system capable of processing password entries. Abraham Shanzer and colleagues describe their "molecular keypad lock" in the Jan. 17 issue of the weekly Journal of the American Chemical Society.

Electronic keypad locks long have been fixtures on home security systems and other devices that require a password.