Re: What are the eating habits of ants?

Ants eat a lot of different things, depending on species. Many are almost 
omnivores (they eat just about anything from dead insects to seeds, but 
not usually leaves), others are carnivores (army ants for example), seed-
feeders (harvesting ants), fungus-feeders (use leaves for fertilizer and 
growing medium), or feed primarily on nectar (honey ants for example.) 
Ants have just about conquered every non-aquatic habitat, except the Polar 
Regions and are among the most successful of organisms.

Reference:  Hölldobler, B., and E. O. Wilson. 1990. The Ants.  Belknap 
Press of Harvard, Cambridge, MA. 732 p.