Cats Are Deadly Unstoppable Killing MachinesAccording to a Nature.com article, domestic and free-ranging cats are responsible for 47% of bird deaths per year and many scientists believe they are destroying important eco-systems.By by Ryan BroderickBuzzFeed News ReporterPosted on January 29, 2013, 7:25 pmTwitterFacebookLink Domestic cats have contributed to multiple wildlife extinctions on various islands around the world. The magnitude of cat-related deaths that happen to wildlife each year in the United States is still unclear. It's estimated that they kill somewhere between 1.4–3.7 billion birds... ...and 6.9–20.7 billion mammals in the U.S. annually. Free-range cats contribute to far more deaths than previously thought. It's likely that cats are the greatest man-made or human-related source of mortality for birds and mammals in the U.S. So now you know. Cats are not nice. Cats are not your friend. They are deadly, tiny, adorable killing machines. Read the full abstract here. nature.com