Territoriality, sociality and male weaponry shape horn investment in female bovids

Male weaponry is well understood and extensively studied across taxa, while female weaponry remains understudied, and the reasons why females bear similar traits are still unclear. In the horned family Bovidae, males possess horns for sexual contests, but the presence and size of female horns vary considerably. Previous research has suggested that female weaponry may assist in intraspecific competition for territory and/or serve as an anti-predator defense in more exposed species. However, these studies did not fully explore how socio-ecological factors might influence variation in female horn length. In this study, we revisited the impact of socio-ecological factors on horn presence and conducted more robust tests of their effects on relative weapon investment (WQ). Our family-level comparative analyses (N = 115) reaffirmed that female territorial behavior and body size are the strongest predictors of female horn presence. For relative weapon investment, we found that among species whe..., Horn Investment
 Maximum female and male horn lengths (HL: in cm), shoulder heights (SH: in cm), and body masses (BM: in kg) were collected from the Bovids of the World field book (Castelló 2016). We chose to only use morphological data from this source to control for measurement consistency, and this book provided the most updated and detailed information on female horns. Our final dataset included 80 female horned species and 35 hornless species (Fig. 1).
We adapted a traditional method used to calculate relative brain size –  ‘encephalization quotient’ [EQ] (Boddy et al. 2012) to calculate investment in horn size or ‘Weapon Quotient’ [WQ] for each sex. This method has recently been adapted to estimate relative weapon investment for tusks, horns, and antlers (Lopez et al., 2024). We first ran phylogenetically corrected linear regressions across all species separately for each sex: log10 HL vs log10 BM. We pruned the Upham et al. (2019) DNA-based consensus mammal-wide tree to..., # Territoriality, sociality and male weaponry shape horn investment in female bovids

Dataset DOI: [10.5061/dryad.fxpnvx16w](https://doi.org/10.5061/dryad.fxpnvx16w)

## Description of the data and file structure

### Files and variables

#### File: Alloutput.nex

**Description:** 300 tree sample from Upham et al. 2019 including all 115 species analyzed in this study.

#### File: FemHoroutput.nex

**Description:** 300 tree sample from Upham et al. 2019 including 80 female horned species analyzed in this study.

#### File: BEHECO-2025-0139_Dyrad_Code.R

**Description:** Final R code including pgls, Bayesian hurdles, ANOVAs, LOO model reductions, and visualizations/plots

#### File: BEHECO-2025-0139.R2_Data.csv

**Description:** Final dataset (.csv) with all variables for all 115 species analyzed in this study

##### Variables

* Binomial: Genus_species
* Species: Genus_species
* Tribe: Bovid Tribe ID
* Tribe ID: Catergorical ID for Anovas/Plots
* Female Horn Length : Maximum published fe...,