The stem cells claimed to be extracted from the first cloned human embryo by discredited scientist Woo Suk Hwang actually owe their existence to parthenogenesis, in which egg cells give rise to embryos without being fertilized by sperm. A series of genetic markers sprinkled throughout the cells' chromosomes shows the same pattern found in parthenogenetic mice as opposed to cloned mice. The result, published online August 2 by Cell Stem Cell, suggests that Hwang and his group were the first to achieve human parthenogenesis but failed to recognize it. (International Stem Cell in Oceanside, Calif., announced successful human parthenogenesis this past July.) Parthenogenesis may offer a way of creating cells that are genetically matched to a woman for disease treatment. —JR Minkel


Nearly 40 percent of all fatal traffic accidents in the U.S. involve drinking, resulting in 17,000 annual deaths. A surefire way to prevent some of these accidents: take away on the spot the license of anyone who fails a breath test. Investigators reporting in the August Alcoholism: Clinical and Experimental Research describe how they analyzed 26 years of federal crash data from 46 states with driver's license suspension laws and confirmed that immediate suspension reduced the number of such fatalities by 5 percent. Legal scholars note, however, that suspensions without due process may violate civil rights. —Coco Ballantyne


Female lab mice tend to be docile, passive creatures. But by either genetically shutting down or surgically removing their ability to smell pheromones, scientists transformed them into aggressive, pelvicthrusting, vocalizing lotharios—without any significant rise in male hormones. The key to the behavioral change is a cluster of receptors in their nose called the vomeronasal organ, which connects to the brain and registers the gender of other mice, triggering the appropriate response. The study, published online August 5 by Nature, suggests that gender-specific behaviors may have less to do with hormones and more to do with how neural circuitry gets triggered. —David Biello