In the early 1900s, fire ants came to the mainland United States aboard ships that had docked in their native South America. Within several years, fire ants had spread across the southern United States. Today, many products are available to control fire ants. However, when all fire ants are eradicated from an area, many different species of ants begin to cause disturbances. When one fire ant mound is reintroduced, no other ants cause problems. What could explain this behavior?

Question

In the early 1900s, fire ants came to the mainland United States aboard ships that had docked in their native South America. Within several years, fire ants had spread across the southern United States. Today, many products are available to control fire ants. However, when all fire ants are eradicated from an area, many different species of ants begin to cause disturbances. When one fire ant mound is reintroduced, no other ants cause problems. What could explain this behavior?

Kenneth Ross: History of Red Imported Fire Ant - Entomology & Nematology News - ANR Blogs

a
Because fire ants are an introduced species, they do not socialize with the other ants. When they are removed, the other ant species become more active.
b
Only the fire ants are becoming resistant to the chemical pesticides.
c
Fire ants do not allow any other ants in their territory, but when they are eradicated, the other ants can resurface.
d
All the species of ants are dying out because of the warmer weather.

Answer 1

c

Fire ants are known for their aggressive behavior towards other ant species, so when they are eradicated from an area, the other ant species are able to thrive and become more active. When a fire ant mound is reintroduced, the fire ants quickly establish dominance and prevent other ants from causing disturbances.