Recent invasions appear to have originated in the U.S. South
Genetic evidence now spotlights the United States as the source of recent fire ant invasions in the rest of the world.
The aggressive, stinging fire ants (Solenopsis invicta) aren’t native to the United States but rather to a broad swath of South America. Yet the southern United States, invaded by fire ants in the 1930s, has sent off at least eight separate waves of fire ant invasions to other countries in recent years, says entomologist Kenneth Ross of the University of Georgia in Athens. A ninth invasion probably hopscotched from the South to California before hitting Taiwan.
“It’s not good news,” Ross says. These waves of ants are now colonizing the Caribbean, Australia, New Zealand, Taiwan and China, including Hong Kong and Macau, he and his colleagues report in the Feb. 25 Science.