A comprehensive assessment of the risk factors for preventable deaths in the United States has found that smoking and high blood pressure are responsible for the greatest number of preventable deaths – each accounting for around 1 in 5 deaths in US adults. The study, published in the open-access journal PLoS Medicine this week, finds that other dietary, lifestyle and metabolic risk factors also cause a substantial number of deaths in the United States.

Many dogs are put down or abandoned due to their violent nature, but contrary to popular belief, breed has little to do with a dog's aggressive behaviour compared to all the owner-dependant factors. This is shown in a new study from the University of Córdoba, which includes breeds that are considered aggressive by nature, such as the Rottweiler or the Pit Bull. The conclusions, however, are surprising: it is the owners who are primarily responsible for attacks due to dominance or competition of their pets.

All fish have ears buried inside their heads. But fish that live in the deepest, darkest waters of the ocean may have particularly sensitive ears says Xiaohong Deng of the University of Maryland. She will be presenting the first anatomical evidence suggesting that some deep-sea fish have specialized structures to heighten their hearing.

The types of fish that Deng studies live in layers of the ocean that no sunlight can reach -- from 400 meters all the way down to depths of 4,000 meters. Biologists are currently unable to keep these mesopelagic and benthopelagic fish alive for very long at the surface, so knowledge about how they function comes from comparing their anatomy to other kinds of fish that live in surface waters.