Behavioural ecology of defence in a risky environment: caterpillars versus ants in a Neotropical savanna

Autor(es)

Sendoya, Sebastian F. ; Oliveira, Paulo S.

• Tipo de documento: Artigo Científico
• Fonte: ECOLOGICAL ENTOMOLOGY; v. 42, n. 5, p. 553-564, OCT 2017.
• Citações Web of Science: 2

Resumo

1. Predatory ants may reduce infestation by herbivorous insects, and slow-moving Lepidopteran larvae are often vulnerable on foliage. We investigate whether caterpillars with morphological or behavioural defences have decreased risk of falling prey to ants, and if defence traits mediate host plant use in ant-rich cerrado savanna. 2. Caterpillars were surveyed in four cerrado localities in southeast Brazil (70-460 km apart). The efficacy of caterpillar defensive traits against predation by two common ant species (Camponotus crassus, C. renggeri) was assessed through experimental trials using caterpillars of different species and captive ant colonies. 3. Although ant presence can reduce caterpillar infestation, the ants' predatory effects depend on caterpillar defence traits. Shelter construction and morphological defences can prevent ant attacks (primary defence), but once exposed or discovered by ants, caterpillars rely on their size and/or behaviour to survive (secondary defence). 4. Defence efficiency depends on ant identity: C. renggeri was more aggressive and lethal to caterpillars than C. crassus, Caterpillars without morphological defences or inside open shelters were found on plants with decreased ant numbers. No unsheltered caterpillar was found on plants with extrafloral nectaries (EFNs). Caterpillars using EFN-bearing plants lived in closed shelters or presented morphological defences (hairs, spines), and were less frequently attacked by ants during trials. 5. The efficiency of defences against ants is thus crucial for caterpillar survival and determines host plant use by lepidopterans in cerrado. Our study highlights the effect of EFN-mediated ant-plant interactions on host plant use by insect herbivores, emphasizing the importance of a tritrophic viewpoint in risky environments. (AU)

• Processo FAPESP: 12/23399-3 - Interações entre formigas e plantas com nectários extraflorais: padrões comunitários ao longo de um gradiente latitudinal no bioma do cerrado
• Beneficiário: Sebastian Felipe Sendoya Echeverry
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/23141-1 - Ecologia de interações, ecologia comportamental e biologia molecular de formigas neotropicais
• Beneficiário: Paulo Sergio Moreira Carvalho de Oliveira
• Linha de fomento: Auxílio à Pesquisa - Programa BIOTA - Regular
• Processo FAPESP: 11/18580-8 - Estudos sobre formigas neotropicais: interações com insetos herbívoros, ecologia comportamental e organização social
• Beneficiário: Paulo Sergio Moreira Carvalho de Oliveira
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/59881-5 - Variação espacial em sistemas multi tróficos: plantas hospedeiras e defesa contra formigas em borboletas no cerrado
• Beneficiário: Sebastian Felipe Sendoya Echeverry
• Linha de fomento: Bolsas no Brasil - Doutorado
• Processo FAPESP: 12/23671-5 - Interações entre formigas e plantas com nectários extraflorais: padrões comunitários ao longo de um gradiente latitudinal no bioma do cerrado
• Beneficiário: Paulo Sergio Moreira Carvalho de Oliveira
• Linha de fomento: Auxílio à Pesquisa - Regular