Background extinction due to species specialization? Insights from a high-resolution Jurassic ammonoid case study (Dactylioceratidae)

The extinction of clades outside mass extinction events remains an understudied aspect of evolutionary dynamics. This study examines the Dactylioceratidae, an ammonite family that disappeared during the Early Jurassic, outside a recognized mass extinction event. By using high-resolution taxonomic (species-level) and temporal (sub-chronozone) data, we assess its evolutionary trajectory, from diversification to extinction. Our analysis reveals that Dactylioceratidae experienced an initial expansion in diversity and geographic range, followed by increased specialization. Morphological disparity and diversity peaked before a sharp decline, suggesting a possible link between ecological specialization and extinction risk. This pattern aligns with hypotheses proposing that over-specialization limits adaptability, leading to extinction under background conditions. In contrast to mass extinctions driven by sudden catastrophic events, background extinctions may be influenced by gradual ecological..., , This README file was generated on 2025-11-14 by Pascal Neige

## Dataset title

Background extinction due to species specialization? Insights from a high-resolution Jurassic ammonoid case study (Dactylioceratidae)

## Date of Data Collection

Compilation of data and measurements made from june 2022 to june 2024.

## Contributors

Pascal Neige, Université Bourgogne Europe, CNRS, Biogéosciences UMR 6282, 21000 Dijon, France\
Twan van Tiel, Université Bourgogne Europe, CNRS, Biogéosciences UMR 6282, 21000 Dijon, France

## Overview

This supplementary dataset, integral to our research paper, contains data crucial for understanding the key findings of our study. It includes a classification of Dactylioceratids (Supplementary Table S1), the calculation of geological ages used to generate figures of the paper (Supplementary Table S2), the complete database (Supplementary Table S3), the complete list of publications taken into account to constitute the database (Supplementary Table S4), and Da..., , **Changes after Nov 17, 2025:** 

Supplementary_Fig._S5 has been renamed Supplementary_Fig._S1 at the request of Paleobiology, the journal of the original article using this dataset.