Extrafloral nectar fuels ant life in deserts

Dorymyrmex planidens ants on an EFN secreting cladode bud of the desert cactus Tephrocactus articulatus.
Dorymyrmex planidens ants on an EFN secreting cladode bud of the desert cactus Tephrocactus articulatus.

Many ant–plant associations are mediated by extrafloral nectaries (EFNs): nectar-producing structures not related to pollination and commonly found on leaves and inflorescences. These sweet secretions represent a critical energy resource for many ant species and constitute the basis for protective mutualisms: by providing ants with food, ants protect plants from herbivores. Although EFN-bearing plants occur in a wide range of habitats and climates worldwide, interactions mediated by EFN-bearing plants are poorly documented in deserts. In a recent article published in AoB PLANTS, Aranda-Rickert et al. show that, in a seasonal desert of northwestern Argentina, biotic interactions between EFN-bearing plants and ants are ecologically relevant components of deserts, and that EFN-bearing plants are crucial for the survival of desert ant communities.