6. Brown Tree Snake
Like the name suggests, this a brown snake that is mostly found on trees. They are native to Northern Australia and Papua New Guinea. The main reason why these snakes are very likely to take over the world is their ability to cause terror and their enormous breeding abilities.
With none of their natural predators around, these snakes have practically taken over the island of Guam. On an island that is about two miles long, there are more than two million brown tree snakes. They are so many that they have been considered an invasive species.