The 17th annual Great Backyard Bird Count takes place worldwide February 14-17. It's your chance to help scientists track the health of bird populations.
Thousands are being evacuated on densely populated island of Java. Eruption took place 90 minutes after alert status for volcano was raised to highest level.
Ten thousand years ago, large mammals of the Arctic, like the woolly mammoth, went extinct. What caused it? Climate change? Disease? Over-hunting by humans?