Ants regulate colony spatial organization using multiple chemical road-signs

Abstract

Communication provides the basis for social life. In ant colonies, the prevalence of local, often chemically mediated, interactions introduces strong links between communication networks and the spatial distribution of ants. It is, however, unknown how ants identify and maintain nest chambers with distinct functions. Here, we combine individual tracking, chemical analysis and machine learning to decipher the chemical signatures present on multiple nest surfaces. We present evidence for several distinct chemical ‘road-signs' that guide the ants' movements within the dark nest. These chemical signatures can be used to classify nest chambers with different functional roles. Using behavioural manipulations, we demonstrate that at least three of these chemical signatures are functionally meaningful and allow ants from different task groups to identify their specific nest destinations, thus facilitating colony coordination and stabilization. The use of multiple chemicals that assist spatiotemporal guidance, segregation and pattern formation is abundant in multi-cellular organisms. Here, we provide a rare example for the use of these principles in the ant colony.

Interdisciplinary approaches for uncovering the impacts of architecture on collective behaviour

“…For example, odours and acoustics can impact the way individuals interact [9]. Social insects relay on the odour of the chambers they occupy to determine what type of task is performed in them [10]. Acoustic signals, such as stridulating, can shape the way social insects move in their nest and structure them [11].…”

“…To allow for reliable long-term tracking of individuals in highly dense social environments, researchers have augmented image analysisbased strategies with unique identification tags. This includes tags such as colours [40] or QR codes (two-dimensional barcodes), which have now been deployed on ants [10,28,41], honeybees [42] and bumblebees [43]. Most of this work is confined to laboratory conditions.…”

Worker demography and behavior in a supercolonial ant colony: The case of the desert antCataglyphis niger

“…Theoretically, nepotistic interactions should be favored unless they negatively affect the society's overall fitness. Interactions between nestmates in an ant colony play a crucial role in establishing a successful self-organization and have been the subject of multiple recent studies (Heyman et al, 2017;Mersch, Crespi, & Keller, 2013;Pinter-Wollman, Wollman, Guetz, Holmes, & Gordon, 2011).…”

Colony‐level chemical profiles do not provide reliable information about colony size in the honey bee

“…It changes with environmental factors, such as nest substrate (Breed et al ., ), colony diet (Liang & Silverman, ) or colony composition (van Zweden et al ., ). In Camponotus fellah , workers mark nest areas with chemical ‘road signs’ that help spatially organize workers within the dark nest (Heyman et al ., ). The developmental state of a colony can also be reflected in its chemical profile.…”