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Aliens Are Coming
Whether deliberate or a complete accident (d'oh), humans have introduced invasive mammals at least 740 times in Europe, according to a study published in the September 2012 issue of the journal Integrative Zoology. The researchers documented the date of more than 630 of the first landings. Here are 14 of the worst, and weirdest, of those invaders, including when and where they invaded.