These are the world's 10 worst invasive species

It's easier than ever for non-native species to invade someone else's home.

Thanks to huge improvements in the way we travel around the globe, species can hitch rides on boats, travel via imported wood, and even enter through people's suitcases when they bring them home from exotic vacations.

So which invaders are causing the most trouble in their new turf?

These 10 are the absolute worst.

Lionfish, originally from the Indo-Pacific, probably got into the Atlantic Ocean from someone's aquarium. They eat over 40 other fish species, as well as each other if they've eliminated other options.

Source: National Geographic

The Burmese python, which can grow up to 22 feet, is eating up the Everglades after people disposed of their unwanted pet snakes there.

Sources: The New York Times, Smithsonian

European starlings started with a flock of 100 in Central Park in 1890. Now, they're all over North America, stealing other birds' nests along the way.

Source: US Forest Service