Since fire ants were accidentally introduced into the United States during the twentieth century, they have plagued both humans and native wildlife.  However, findings of research conducted by biologists at Pennsylvania State University suggest that fence lizards that eat fire ants increase their immunity to the fire ant venom. 

       The researchers found that blood tests of the fence lizards that consumed dead fire ants three times a week developed three different types of increased immunity against the fire ant venom.

       It is interesting to note that being stung by the fire ants did increase the lizards’ immunity against future stings.