Ontogeny of physical trails in atta capiguara gonçalves 1944 (Hymenoptera: formicidae)

Author(s)

Nádia Caldato

• Document type: Doctoral Thesis
• Press: Botucatu. 2015-03-03.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agronômicas. Botucatu
• Defense date: 2014-12-05
• Advisor: Luiz Carlos Forti; Juliane Floriano Santos Lopes

Abstract

Ants, especially those that leaf cutting ants, perform an extremely important role in ecological systems. These insects may be considered true engineers of ecosystems since they actively modify the environment. Remarkably, their foraging activity on the soil surface causes considerable “damage” to vegetation, being able to actively compete with cattle, in the case of grass-cutting species. The present study aimed to investigate in the field the ontogeny, maintenance, distribution and utilization of foraging network trails in Atta capiguara. Basically, four hypotheses were tested: I) There is a daily rhythm in foraging activity that varies as a function of dry and wet seasons; II) These ants present a pattern in the utilization and construction of a network of physical trails in time and in space; III) How much time is spent by the ants restoring the physical trails. IV) The ants deposit substances for a herbicidal function onto trails with the aim of keeping them free of vegetation. The data enable the modeling of the collective foraging activities of this specie. A. capiguara presented two daily foraging journeys, one in daytime and one at night that varied as a function of dry and wet seasons. Foraging peaked at temperatures between 20 and 25ºC and relative air humidity of 75 to 80%. In the wet season, the foraging of ants bearing a load was more intense. Although the results obtained indicate that the parameters evaluated interfere in the foraging of A. capiguara, it is suggested that besides these factors, other parameters were influencing the rhythm foraging, for example the total number of active trails or the nutritional requirements of the colony. It is also possible that the circadian rhythm of this specie was linked to the lightdarkness alternation. As to the pattern of trail network utilization, an elevation was observed in the number of hole across time ... (AU)

• FAPESP's process: 11/00369-9 - Ontogeny, maintenance, distribution and use of space-time in physical network of trails Atta capiguara
• Grantee: Nadia Caldato
• Support Opportunities: Scholarships in Brazil - Doctorate