Ancestral complexity and constrained diversification of the ant olfactory system

Communication is a cornerstone of social living, allowing the exchange of information to align goals and synchronize behaviour. Ants, a group of highly successful social insects, have heightened olfactory abilities that are integral to their evolutionary success. Essential for colony cohesion and cooperation, a female-specific olfactory subsystem processes information about nestmate recognition cues (cuticular hydrocarbons), including basiconic sensilla on the antenna and a cluster of specific glomeruli in the antennal lobe. While it has often been linked to ants’ social lifestyle, the evolutionary origins and phylogenetic distribution of this system remain unknown. We conducted a comparative exploration of the ant olfactory system across eight major subfamilies, integrating neuroanatomical, chemical, and behavioural analyses. Our findings reveal that sophistication of the ant olfactory system has deep evolutionary roots. Moreover, antennal lobe investment is not associated with social ..., , # Ancestral complexity and constrained diversification of the ant olfactory system

Dataset DOI: [10.5061/dryad.5dv41nsh7](10.5061/dryad.5dv41nsh7)

## Description of the data and file structure

This dataset includes 14 video sequences (19 seconds each) showing the antennal lobe organisation of 14 ant species. Each video presents a sequence of confocal microscopy scans and the resulting 3D model of the antennal lobe, illustrating both raw imaging data and segmented glomerular structures. These data were obtained as part of a comparative study on the evolution of olfactory system organisation in ants. Full methodological details, species list, and analyses are provided in *Ancestral complexity and constrained diversification of the ant olfactory system*.

### Files and variables

#### File: Formicidae-AL.zip

**Description:** The dataset includes antennal lobe imaging from the following species:

\* Aphaenogaster senilis

\* Atta sexdens

\* Azteca trigona

\* Camponotus aethiops

\* Ca...,