Scientists Find How Density of Ants Relates to Ecosystem

Scientists at the University of Exeter found that ants have two great effects on the environment, by being both ‘ecosystem engineers' and predators. The scientists studied the impact of different combinations and densities of black garden ants (Lasius niger) and common red ants (Myrmica rubra). They found the ants affect the nutrients within the soil as they move the soil for colony construction and the ants prey on a wide range of other animals, including larger animals. These scientists found that a low population of ants within an area, increased the diversity and density of other animals, particularly herbivores and decomposers. However when the ants were at higher populations, they had no or opposite effects on the presence of other animals. This demonstrates the possibility that ant predation could cause a decrease in other animal species, which could have a negative effect on the ecosystem.

Photo of fire ants. Photo by Bart Drees, Professor and Extension Entomologist, Texas A&M University.