Ants are, hands down, the most successful animal colonizers on the planet and the only animals, large or small, to compete with the large scale of human colonization of planet Earth.
The most successful of all ant species is the Argentine ant. Originally originally in South America, the ant has been slowly spreading, and migrating with humans, all over the world. Argentine ants are well known for forming large colonies with hundreds of millions of ants living in a huge interconnected home.
The largest known Argentine marsh colony extends for approximately 3,700 miles along the Mediterranean and Atlantic coasts of southern Europe. Although not all colonies are so large that they cross dozens of international borders, the world is covered by several mega colonies ̵1; the state of California, for example, has a colony that stretches some 560 miles along the coast.
Even more interesting is that ants from Argentine ant colonies separated by oceans (like those you would find in France and California) recognize each other as members of what corresponds to a global mega colony of Argentine ants and will not attack each other. If they could cross the oceans, Argentine ants from any of the continental colonies could travel undamaged through the tens of thousands of miles of underground roads built by the individual super-colonies.