One cell…one initial set of genetic changes - that's all it takes to begin a series of events that lead to metastatic cancer. Now, Johns Hopkins experts have tracked how the cancer process began in 33 men with prostate cancer who died of the disease. Culling information from autopsies, their study points to a set of genetic defects in a single cell that are different for each person's cancer.

New evidence gleaned from CT scans of fossils locked inside rocks may flip the order in which two kinds of four-limbed animals with backbones were known to have moved from fish to landlubber.

Lack of law enforcement against illegal trade in Indonesia threatens the survival of orangutans and gibbons on Sumatra, a new study by the wildlife trade monitoring network TRAFFIC shows.

During the last 540 million years, the earth's oxygen levels have fluctuated wildly. Knowing that the dinosaurs appeared around the time when oxygen levels were at their lowest at 12%, Tomasz Owerkowicz, Ruth Elsey and James Hicks wondered how these monsters coped at such low oxygen levels. But without a ready supply of dinosaurs to test their ideas on, Owerkowicz and Hicks turned to a modern relative: the alligator. 'We knew testing the effects of different oxygen levels would work with alligators,' Owerkowicz explains, 'because crocodilians have survived in their basic shape and form for 220 million years. They must be doing something right to have survived the oxygen fluctuations.' Choosing to start at the beginning of alligator development, the trio decided to try incubating alligator eggs at different oxygen levels, to find out how the youngsters grew and developed and publish their results on April 17 2009 in The Journal of Experimental Biology at http://jeb.biologists.org.

Many active young women use oral contraceptives (OC) yet its effect on their body composition and exercise performance has not been thoroughly studied. A team of researchers has now examined the effects of OC on female muscle mass, and found that oral contraceptive use impairs muscle gains in young women, and is associated with lower hormone levels.