Was watching the Weather Channel this evening, and a show came on, spent an hour laying out all the ways life - as we know it - might end on the planet. We covered the asteroid/comet/planetoid/big lump of something slamming into the world, then all the results: "nuclear winter", etc. Then we covered massive solar flares and eruptions. Of course we covered a gamma ray burst aimed right at us. That can be deadly from quite a ways away. then there was the supernova within 10LY. Didn't have to come from the sky, we have massive volcanic activity. We have some new disease running rampant.
Once all that jolly news was done, we had a show about how giant snakeheads ( a fish) were taking over our waterways. They can walk on land and breath air too.