Individuals with higher mid-life Body Mass Index (BMI) in the 1960s have been found to have lower memory and thinking skills and a sharper decline in these abilities in old age, compared to those with lower BMI in mid-life.

MicroRNAs are the newest kid on the genetic block. By regulating the unzipping of genetic information, these tiny molecules have set the scientific world alight with such wide-ranging applications as onions that can't make you cry and therapeutic potential for new treatments for viral infections, cancer and degenerative diseases. But the question remains: How do they work?

Slow-flying, woodland bats -- which tend to be at greater risk from extinction than their speedier kin -- really don't like street lights, according to a new study. Lesser horseshoe bats will stray from their usual flight routes to steer clear of the artificial glow from lights that are similar to everyday street lights, the new report shows.

A new study has found a substantial link between increased levels of nitrates in our environment and food with increased deaths from diseases, including Alzheimer's, diabetes mellitus and Parkinson's.

The Helix Nebula, NGC 7293, is not only one of the most interesting and beautiful planetary nebulae; it is also one of the closest nebulae to Earth, at a distance of only 710 light years away. A new image, taken with an infrared camera on the Subaru Telescope in Hawaii, shows tens of thousands of previously unseen comet-shaped knots inside the nebula. The sheer number of knots -- more than have ever been seen before -- looks like a massive fireworks display in space.

Appendicitis is the most common childhood surgical emergency, but can be hard to diagnose, often leading to either unnecessary surgery or serious complications when the condition is missed. Now, emergency physicians and proteomics researchers have identified a urine protein that might serve as a "biomarker" for appendicitis, the most accurate one known to date.

Editor's Note: Scuba instructor and underwater videographer Drew Wheeler is traveling on board the Algalita Marine Research Foundation's 50-foot (15.2-meter) Ocean Research Vessel, Alguita, on a two-month voyage to sample and study portions of a 10-million-square-mile (25.9-million-square-kilometer) oval known as the North Subtropical Gyre (aka "Pacific garbage patch"). Wheeler and the rest of the Alguita crew left Long Beach, Calif., on June 10 with a plan to cross the International Date Line and investigate regions of reported high plastic concentrations, northwest of the Hawaiian Islands. This is his fourth blog post for Scientific American.

July 2, 2009 [More]

Paleontologists have dug up not one but three new dinosaur species in Australia, a continent that has turned up few large fossil finds. The mid-Cretaceous giants include two massive plant-eating titanosaurs--Witonotitan wattsi and Diamantinasaurus matildae--and a fearsome carnivorous theropod--Australovenator wintonesis--reported in a PLoS ONE study last week. [More]

Paleontologists have dug up not one but three new dinosaur species in Australia, a continent that has turned up few large fossil finds. The mid-Cretaceous giants include two massive plant-eating titanosaurs--Witonotitan wattsi and Diamantinasaurus matildae--and a fearsome carnivorous theropod--Australovenator wintonesis--reported in a PLoS ONE study last week. [More]

Researchers subjected species found in Antarctic waters to increasing levels of water temperature to learn how well they would cope with a warmer ocean. The study shows that several of these species are already living really close to their upper temperature range, and that further increases could easily provoke serious ecological imbalances in this region.