Ant behavior towards Homoptera in the presence of Chrysoperla carnea and Hippodamia convergens predators.

Abstract

This study investigated the behavior of ants and their mutualistic relationship with aphids on Asclepias syriaca (milkweed) plants. Mutualistic systems have existed for years and been the focus of much study. Examining the various interactions within nature helps provide a more detailed understanding of the ecology of the systems we inhabit. This understanding can prove invaluable in creating management systems and agricultural projects. I examined the different protective and non-protective behaviors exhibited by the ants towards the aphids with and without the presence of predators. Previous studies of the ant/aphid system have concentrated on the benefits derived by the aphid and not much attention has been paid to ant behavior. Milkweed plants containing both aphids and ants were selected from the campus of UMBS, Pellston, MI, USA. Ant behaviors were recorded for the systems in the presence of two different aphid predators, lacewing larvae and lady beetles and without predators. These behaviors were quantified as either protective (tending, attacking, assistance) behaviors or non-protective (leaving, ignoring) behaviors in relation to the aphids. Five replicates were performed on six independent plant systems and the data analyzed with X2 tests. The data indicated that, overall, the ants consistently performed protective behaviors and that increased in the presence of predators. This suggests that the ants not only tend ants to obtain a food source but also protect that food source from predation. This system can be used to further understand other mutualistic relationships and be related to possible, beneficial uses in agriculture and horticulture.