Adaptive radiation of pelagiarian fishes at the K/Pg boundary led to rapid diversification of mandible morphology

Mandibles represent a key evolutionary innovation that have enabled jawed vertebrates to adapt and diversify in response to a range of food sources, and changes in mandible shape are often linked with adaptive radiations into new ecological niches. Using a phylogenetic comparative approach, we explore the phenotypic disparity and mechanical properties of the lower jaw in Pelagiaria, a morphologically diverse but relatively small clade of open-ocean fishes which arose near the Cretaceous/Paleogene (K/Pg) mass extinction event. Using three-dimensional (3D) geometric morphometrics, we find that the high phenotypic disparity of the pelagiarian mandible was established very early in their evolutionary history, and high levels of disparity have been maintained over tens of millions of years; this is consistent with the hypothesis that Pelagiaria represents an ancient adaptive radiation. We test the correlation of mandible shape with potential drivers of shape evolution, and find that mandible..., , # Adaptive radiation of pelagiarian fishes at the K/Pg boundary led to rapid diversification of mandible morphology

Dataset DOI: [10.5061/dryad.n2z34tnbm](https://doi.org/10.5061/dryad.n2z34tnbm)

## Description of the data and file structure

This repository contains all data, scripts, and supplementary figures from \"Adaptive radiation of pelagiarian fishes at the K/Pg boundary led to rapid diversification of mandible morphology.\"

## Code/software

All code is written for R (v. 2024.12.1+563), with required packages labelled at the start of each script. Packages should be installed prior to running scripts.

The scripts for replicating this study should be run in order.

## Morphometrics

### 1.1 Contents

`morphometrics.zip`: Run through scripts in 'scripts' folder in numbered order.

```
morphometrics
┣ input_data
┃ ┣ mandible_resampling_template.csv
┃ ┣ mandible_specimen_data.csv
┃ ┗ mandible_tree.nex
┣ output_data
┃ ┣ PCA.3D.rda
┃ ┣ slidedlms.mandible.rda
┃ ┗ Y.gpa.rda
┣ ply_ASCI...,