One of the reasons HIV is so difficult to contain and treat is its rapid evolution. Understanding how host defenses and viral countermeasures contribute to that evolution is vital.

Sandia National Laboratories has completed a two-year study of the potential health effects associated with accidental exposure to depleted uranium (DU) during the 1991 Gulf War.

Saving large mammals such as elephants and rhino from extinction could be made more effective by focusing efforts on individual species as well as their habitats.

An international team that includes researchers from the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health (NIH), has discovered that mammalian chromosomes have evolved by breaking at specific sites rather than randomly as long thought – and that many of the breakage hotspots are also involved in human cancer.

Basking sharks are much more canny predators than previously thought, ecologists have discovered. According to new research published online by the British Ecological Society's Journal of Animal Ecology, basking sharks are able to reverse their normal pattern of diving at dawn and surfacing at dusk in order to foil the attempts of zooplankton trying to evade capture. As well as shedding new light on basking behaviour, the results have important implications for the conservation of shark species.