Natural History of Ants: What We (do not) Know About Trophic and Temporal Niches of Neotropical Species

摘要

Our understanding of the natural history of Neotropical ants is still limited, both due to a lack of detailed descriptive efforts and the widespread use of morphospecies in community studies. Use of trophic resources and period of activity are two central niche aspects little explored for most species. This work aims to review the literature and provide empirical field data on these aspects for several species. The fieldwork was carried out in the Atlantic forest of southern Brazil. Trophic and temporal niches were assessed with pitfall traps and seven kinds of bait representing natural resources available to ants. Crushed insects were the preferred resource, whereas bird feces and living prey were less exploited overall. Most of the species occupied a broad trophic niche, using several resources, but with pronounced quantitative differences. Odontomachus chelifer (Latreille, 1802) and Pachycondyla striata Smith, 1858 were the only species that consistently used large prey, and avoided trisaccharides. Wasmannia auropunctata (Roger, 1863) differed remarkably from previous accounts, using feces as its sole trophic resource. Pheidole species had no previous records and use resources in different ways. Most species had no strong preference for period of activity. Camponotus zenon Forel, 1912 was nocturnal and Crematogaster nigropilosa Mayr, 1870, Linepithema iniquum (Mayr, 1870) and Linepithema pulex Wild, 2007 were diurnal. Complementary methods, context-dependence and descriptive studies have a central role in the understanding of ant natural history. Community assessments can contribute significantly to this knowledge if researchers also pay attention to the individual species involved.