Tropical Fire Ants were shipped across the globe by Spanish traders in their ships, nearly 500 years ago.
The world is a home for humans as well as all other creatures, in fact most of the species are far senior to Homo sapiens and have developed much stronger mechanisms to survive. The only difference then and now is the easy of spread of these insects from one geographic location to another.
Earlier the spread was not as fast as it is now because these can even travel on an airplane with our luggage. Honey
bees, when first arrived in North America in 1620 with British travellers, the Native Americans, who had never seen them before, reportedly referred to them as “white man’s flies.”
Now researchers have discovered an even earlier example. According to a study published in the journal Molecular Ecology, tropical fire ants (Solenopsis geminata) were stowaways on Spanish ships as early as the mid-1500s, which brought them from Acapulco, Mexico to the Philippines and from there to other parts of the world. Today, the ant species is found in virtually all tropical regions, including Africa, the Americas, Australia, India, and Southeast Asia.
The ships from all over Europe were going out somewhere to pick up commerce, would fill their ballast with soil and then they would dump the soil out in a new port and replace it with cargo and this way along with the soil the ants were paving their way into the ship. Now loaded ships were unknowingly moving huge numbers of organisms in the ballast soil.
Upon analysis of the genomes of large number of fire ants from around 200 locales depending upon their genetic diversity and other patterns and then matching these with the trading routes of the Spanish ships going out and returning during the mid-1600s the researchers concluded on the spread and routes.
Dr. Suarez, in his writings mentioned that upon a closer look at the records of trading routes and genetic patterns, all paints this picture that this was one of the first global invasions, and it coincided with what could be the first global trade pattern of the Spanish and these ants from the introduced areas in the Old World are genetically most similar to ants from southwestern Mexico, suggesting that their source population came from this region.
Information as published in entomologist today