Keeping tropical rain forests intact is a better way to combat climate change than replacing them with biofuel plantations, according to a new study published in Conservation Biology.

The study reveals that it would take at least 75 years for the carbon emissions saved through the use of biofuels to compensate for the carbon lost through forest conversion. And if the original habitat was carbon-rich peatland, the carbon balance would take more than 600 years. On the other hand, planting biofuels on degraded Imperata grasslands instead of tropical rain forests would lead to a net removal of carbon in 10 years, the authors found.

A new picture of the early Earth is emerging, including the surprising finding that plate tectonics may have started more than 4 billion years ago — much earlier than scientists had believed, according to new research by UCLA geochemists. 

"We are proposing that there was plate-tectonic activity in the first 500 million years of Earth's history," said geochemistry professor Mark Harrison, director of UCLA's Institute of Geophysics and Planetary Physics and co-author of the Nature paper. "We are reporting the first evidence of this phenomenon." 

SARS – severe acute respiratory syndrome – alarmed the world five years ago as the first global pandemic of the 21st century. The coronavirus (SARS-CoV) that sickened more than 8,000 people – and killed nearly 800 of them – likely originated in bats, though the actual animal source is not yet known.

Children whose eyes are misaligned and point outward are at significantly increased risk of developing mental illness by early adulthood, according to findings of a Mayo Clinic study published this month in Pediatrics (http://pediatrics.aappublications.org/cgi/content/full/122/5/1033), the official journal of the American Academy of Pediatrics.

Hormone therapy could accentuate certain pre-existing heart disease risk factors and a heart health evaluation should become the norm when considering estrogen replacement, new research suggests. 

The research also showed that in women without existing atherosclerosis, hormone therapy use included some positive effects on lipids but also some negative effects related to heart health, said MaryFran Sowers, lead researcher and professor of epidemiology at the University of Michigan School of Public Health. 

Registration is open for NASA's 16th annual Great Moonbuggy Race, taking place April 3-4, 2009, in Huntsville, Ala.   The race was founded at NASA's Marshall Space Flight Center in Huntsville in 1994. The U.S. Space and Rocket Center hosts the two-day event. The nationally renowned space museum and tourist attraction constructs a punishing course - a half-mile of hills and craters simulating the lunar surface - on the looping sidewalks and paths around its grounds.