That reminded me of once reading about some ants
treating aphids as "cattle"...
Ahh...here it is:
"European red fire ants have a sweet tooth and thrive on sugary
liquid waste called
honeydew secreted by aphids, another
of the state's (Maine) pests, said Eleanor Groden, an entomologist.
"They will tend aphids like little cattle that they farm," Groden said.
http://www.usatoday.com/tech/science/20 ... ants_x.htm