Polar bears are thriving in Svalbard, and more...

Scientists spent nearly 25 years studying close to 800 polar bears in the Barents Sea region and discovered that those polar bears seem to be doing just fine, even though melting sea ice is also a major issue. PLUS: Sargassum seaweed is becoming such a problem, you can see it from spaceWhy some people only get mild sniffles with a cold and others get sickA woolly rhino's DNA found in an ancient wolf’s stomach reveals their quick demiseHow to change a memory — one scientist's quest to understand memory permanence