Covariation between morphological traits and ant-following behavior in Neotropical birds

Some species rely on others to obtain part, or in extreme cases all, of their food. For example, ant-following birds exploit insects that are disrupted by swarms of army ants. Such behavioral specialization is often linked to the evolution of morphological traits that enhance resource exploitation. In this study, I investigated whether morphological traits covary with ant-following behavior. I predicted that traits than enhance competitive ability, like a heavier weight and signals of dominance, should be more prevalent in species that rely more on ants to obtain food. Other morphological traits were also expected to diverge reflecting the unique lifestyle of ant-following birds. I focused on Neotropical families that include obligate ant-following species, as well as others that follow ants frequently, occasionally, or not at all—thus providing a gradient of ant-following behavior. Using a phylogenetic framework that incorporated primary lifestyle and foraging behavior, I identified se..., Data collection
I searched the literature for studies reporting ant-following behavior in Neotropical birds. I focused on suboscine passerine families where the behavior occurs frequently including Thamnophilidae, Dendrocolaptidae, Conopophagidae, and Formicariidae (Martínez et al. 2021). Within the suboscines, I excluded the Furnariidae, a large family where ant-following is not common and when it occurs considered rare (Roberts et al. 2000; Pizo and Melo 2010; Sazima and D'Angelo 2015; O'Donnell 2017). Ant-following is also considered rare in the Tyrannidae (Willis 1983b), another large family closely related to the Furnariides, one of the three infraorders of suboscine passerines (Harvey et al. 2020).
I gathered information on ant-following behavior from species accounts in Birds of the World (https://birdsoftheworld.org) and also performed searches on Google Scholar combining each species name and the key words ant or ant-following. Based on available evidence, ant-following behavio..., # Covariation between morphological traits and ant-following behavior in Neotropical birds

Dataset DOI: [10.5061/dryad.4tmpg4fq6](https://doi.org/10.5061/dryad.4tmpg4fq6)

## Description of the data and file structure

This dataset contains the data for the analyses reported in Beauchamp (2025). I focused on Neotropical families that include obligate ant-following species, as well as others that follow ants frequently, occasionally, or not at all—thus providing a gradient of ant-following behavior. Using a phylogenetic framework that incorporated primary lifestyle and foraging behavior, I identified several morphological changes in ant-following species. The dataset provides a list of the species used in the analyses along with all measurements obtained from the literature.

### Files and variables

#### File: dataset.xlsx

**Description:** Complete dataset

##### Variables

* species (name of the species used in the phylogeny)
* family (name of the family)
* ant-following behavior (A...,