Exploring the morphospace of cidaroid echinoid spines.

Crown group cidaroids (Echinodermata: Echinoidea: Cidaroida) display a variety of spine morphologies thought to be adapted in response to selective pressures around them. Echinoid spines directly interact with their surroundings and morphologies should reflect environmental conditions changing through time. To quantify trends in morphology through time, 2D geometric morphometrics were applied to cidaroid spines to track changes in morphospace. This was completed through four anatomical landmarks and 250 semi-landmarks to grasp the entirety of the spine shape. Once plotted into multivariate space, trends related to time and morphology were found within one family of cidaroids, Psychocidaridae. These trends coincided with major geologic events, such as the Marine Mesozoic Revolution and Cretaceous-Paleogene extinction. Contractions and shifts in morphospace could then be related to predation and changes in marine community structure. Additionally, modern cidaroids display an expansive morphological diversity, while not being taxonomically diverse.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Masters

Grantor

Baylor University.

Year dc:date.issued

2025

Author dc:creator

• Watts, Jerrad D., 2000-

Advisor dc:contributor.advisor

• Petsios, Elizabeth.

• Echinoid.
• Geometric morphometrics.
• Morphology.
• Evolution.

Statement dc:rights

• Baylor University works are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. Contact libraryquestions@baylor.edu for inquiries about permission.

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/2104/13848

OAI identifier oai:identifier

oai:baylor-ir.tdl.org:2104/13848