Are Cats Alien Invaders?

A Polish scientific institute has added house cats to a list of "invasive alien species."

Not that they are otherwordly, but because cats damage biodiversity by hunting and killing birds and mammals.

Biologists at the Polish Academy of Sciences, which maintains the list, were stunned by the reaction of cat lovers, who are furious.

Maybe a certain group of Polish biologists needs to be added to another list: Endangered Species.