Dealing with water deficit in Atta ant colonies: large ants scout for water while small ants transport it

Autor(es)

Da-Silva, Antonio Carlos ^[1] ; Navas, Carlos A. ^[1] ; Ribeiro, Pedro L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biociencias, BR-05508090 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BIOLOGY OPEN; v. 1, n. 9, p. 827-830, SEP 15 2012.
• Citações Web of Science: 3

Resumo

Leafcutter ants (Atta sexdens rubropilosa) (Forel 1908) have an elaborate social organization, complete with caste divisions. Activities carried out by specialist groups contribute to the overall success and survival of the colony when it is confronted with environmental challenges such as dehydration. Ants detect variations in humidity inside the nest and react by activating several types of behavior that enhance water uptake and decrease water loss, but it is not clear whether or not a single caste collects water regardless of the cost of bringing this resource back to the colony. Accordingly, we investigated water collection activities in three colonies of Atta sexdens rubropilosa experimentally exposed to water stress. Specifically, we analyzed whether or not the same ant caste foraged for water, regardless of the absolute energetic cost (distance) of transporting this resource back to the colony. Our experimental design offered water sources at 0 m, 1 m and 10 m from the nest. We studied the body size of ants near the water sources from the initial offer of water (time 5 0) to 120 min, and tested for specialization. We observed a reduction in the average size and variance of ants that corroborated the specialization hypothesis. Although the temporal course of specialization changed with distance, the final outcome was similar among distances. Thus, we conclude that, for this species, a specialist (our use of the word ``specialist'' does not mean exclusive) task force is responsible for collecting water, regardless of the cost of transporting water back to the colony. (C) 2012. Published by The Company of Biologists Ltd. (AU)

• Processo FAPESP: 08/57687-0 - Effects of global climate change of the Brazilian fauna: a conservation physiology approach
• Beneficiário: Carlos Arturo Navas Iannini
• Linha de fomento: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático
• Processo FAPESP: 09/54235-3 - Estudo macro-fisiologico da temperatura crítica máxima de artrópodes no Brasil
• Beneficiário: Pedro Leite Ribeiro
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado