A new study by researchers at the Harvard School of Public Health (HSPH) finds that polio vaccination in the United States has resulted in a net savings of over $180 billion, even without including the large, intangible benefits associated with avoided fear and suffering. This first study to retrospectively demonstrate the enormous benefits of polio vaccination appears as part of a special issue on polio in the December 2006 issue of Risk Analysis.

Mating, sneaking and egg cannibalism in T. sarasinorum. A study from the February issue of the American Naturalist is the first to demonstrate that male fish are more likely to eat their offspring when they have been cuckolded during the act of spawning. Moreover, the more males that are present during spawning, the more likely it is that a male will try to eat the eggs when they are laid, as it is less likely that he fertilized them.

It's no secret why we shed tears. But exactly what our tears are made of has remained a mystery to scientists.