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Archive - Apr 19, 2012

Ravens Remember Relationships with Others

In daily life, we remember faces and voices of several known individuals. Similarly, mammals have been shown to remember calls and faces of known individuals after a number of years. Dr. Markus Boeckle and Dr. Thomas Bugnyar from the Department of Cognitive Biology of the University of Vienna show in a new article, published online on April 19, 2012 in Current Biology, that ravens differentiate individuals based on familiarity. Additionally, they discovered that ravens memorize relationship valence and affiliation. So far it has been unknown whether relationship valence can be remembered based on former positive or negative interactions. As response to calls of formerly known individuals ravens not only increase the number of calls but also change call characteristics dependent on whether they hear former "friends" or "foes." This suggests that ravens remember specific individuals at least for three years. The ability to change call characteristics is especially interesting. In the event they hear a "friendly" individual, they respond with a "friendly" call, whereas when listening to a "foe," they exhibit lower frequencies and rougher characteristics, an effect already described for other animal species. Ravens respond to calls from previously unknown individuals with even lower and rougher calls and thus try to increase their acoustically perceivable body size – also in humans, larger people have lower voices than smaller ones and angry humans rougher voices. While it was known that mammals change their voices based on the relationship they share with others, the researchers here were able to show for the first time that birds also change their calls according to relationship quality.

Scientists Develop Effective Treatment for Deadly Cat Disease

Lone Star ticks, which are notorious carriers of many diseases including cytauxzoonosis, or "bobcat fever," have been spreading across the nation in recent years. As a result, cats across much of the country are now exposed to the deadly disease. University of Missouri veterinarian Dr. Leah Cohn, a small animal disease expert, and Dr. Adam Birkenheuer from North Carolina State University, have found an effective treatment for the dangerous disease. "Previous treatment methods have only been able to save less than 25 percent of infected cats, but our method, which is now being used by veterinarians across the country, has been shown to save about 60 percent of infected cats," Dr. Cohn said. "While that number isn't as high as we'd like due to the deadly nature of the disease, our method is the first truly effective way to combat the disease." Routinely carried by bobcats and mountain lions, Dr. Cohn and Dr. Birkenheuer also found that bobcat fever can even infect tigers. All types of cats, but only cats, can catch bobcat fever. Dr. Cohn calls the disease the "Ebola virus for cats," saying that it is a very quick and painful death for cats that succumb from the infection. Bobcat fever is easily spread between cats through tick bites, but Dr. Cohn and Dr. Birkenheuer found that the disease is not readily passed down through birth like malaria and many other protozoan diseases. "Bobcat fever affects healthy outdoor cats the most, because they are the most likely to get bitten by ticks," Dr. Cohn said. "The disease acts very quickly and can kill a cat less than a week after it begins to show signs of being sick, so it is important to get treatment from a veterinarian as soon as the cat appears ill." Dr.

Landmark Breast Cancer Study Could Revolutionize Diagnosis & Treatment

A major study carried out by Cancer Research UK scientists and collaborators around the world could revolutionize the way women with breast cancer will be diagnosed and treated in the future, by reclassifying the disease into ten completely new categories based on the genetic fingerprint of a tumor. Doctors should one day be able to predict survival more accurately in women with breast cancer based on these new subtypes, and better tailor treatment to the individual patient. The research, published online on April 18, 2012 in Nature, is the largest global gene study of breast cancer tissue ever performed and represents the culmination of decades of research into the disease. The team at Cancer Research UK’s Cambridge Research Institute, in collaboration with the British Columbia (BC) Cancer Agency in Vancouver, Canada, and multiple institutions around the world, analyzed the DNA and RNA of 2,000 tumor samples taken from women diagnosed with breast cancer between five and ten years ago. The scientists classified breast cancer into at least ten subtypes grouped by common genetic features that correlate with survival. This new classification could change the way drugs are tailored to treat women with breast cancer. The investigators also discovered several completely new breast cancer genes that drive the disease. These genes are all potential targets for the development of new types of drugs. This information will be available to scientists worldwide to boost drug discovery and development. The research also revealed the relationship between these genes and known cell signaling pathways, networks that control cell growth and division. This could pinpoint how these gene faults cause cancer, by disrupting important cell processes.