Diversity, distribution and secrets of ant transportation networks

Abstract

One of the most striking examples of transport networks are the trail systems formed and used by several species of ants. Ants forage to find food from a central nest, building a network of trails radiating out to nearby food sources and bring it back to the colony. During the entire tenure of survey 11 ant species trails are encountered in the various locations of study sites. All along, there is a physical contact between the trails of the outgoing and incoming traffics. The way to get back home, after grasping a food load (eggs, larvae, dead carcass of colony members, other invertebrates & vertebrates, sugar cube, plant leaf & seed, piece of bread, etc.) is to follow the up route. In many species such trails are chemically marked by pheromones providing orientation cues for the ants to find their way. Other species count on their faculty of sight and markers as signals. Few opportunistic species like Diacamma scalpratum (Smith), Diacamma vagans (Smith), Tetraponera rufonigra (Jerdon), Tetramorium christiei Forel often abscond themselves in the trail due to search of food. Often only male morphs of few spider species namely Myrmarachne melanocephala MacLeay and Myrmarachne plataleoides O.P.Cambridge are encountered within the ants’ populations in the trail throughout the period of survey. Such a Batesian mimicry exhibited only by the male spiders is possibly an intrinsic escape behaviour from their female mates so as to avoid cannibalism.