Benefits of living underground: the case of parasite release in the antlion Myrmeleon timidus: Antlions and entomopathogenic fungi

The omnipresence of pathogens makes them a strong selective pressure for most organisms, generating a variety of defensive responses to fight them. One mechanism by which organisms can release this pressure is avoidance of the pathogens in a spatial or temporal context. To date, only a few biological systems provide evidence that habitat selection can favour an escape from pathogens. An abiotic factor that varies across habitats and influences the evolution of host life history is humidity, which correlates positively with pathogen levels in the environment. Entomopathogenic fungi are abundant in soils and are obligate killers that require humidity for host infection. Antlions (Neuroptera: Myrmeleontidae) are typical soil‐dwelling insects that can live several years as larvae, buried in dry and fine substrates where they build their traps. This lifestyle may release them from selective pressure by entomopathogenic fungi. Here, we investigated whether living underground provides protection against the generalist entomopathogenic fungus Beauveria bassiana (Bals.‐Criv.) Vuill. in the antlion Myrmeleon timidus Gerstaecker under low or high humidity in the environment. Individuals that were inoculated with the fungus showed greater survival rates when buried in dry sand compared to individuals that were kept half‐buried or without sand, with similar outcomes across humidity levels. Given that the diversity of antlions is higher in arid environments, this benefit obtained from pit‐building behaviour seems to be a coincidental by‐product of this foraging strategy, which would be particularly beneficial in environments where fungal pathogens are common.

Autor: 

Dumas Gálvez
Milagro Garrido
Fermín Gil
Hermógenes Fernández-Marín

Editorial: Estación Científica Coiba AIP
Tamaño: 2.9Mb
Soporte: Digital
Formato: Pdf (.pdf)
Idioma: Ingles