Scientists with the Smithsonian Institute say they have produced statistical evidence that euthanasia and/or mass-sterilization may be the only way to keep a dangerous cat population from destroying the country's wildlife.

According to a new study, every single year in this country, cats stalk and kill 2.4 billion birds and 12.3 billion mammals.

That's two to four times higher than previously believed. And pretty specific, like out a decimal point specific.

Which brings us to tonight's number: Give or take a few billion.

That is, apparently, the margin of error in the study.

Erin Burnett says she usually support scientists on this show. But when it comes to the danger of cats, it seems like they're just telling tales.