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Published on: April 5, 2021
The ocular skeleton through the eye of evo-devo
1Biology Department, Mount Saint Vincent University, Halifax, Nova Scotia, Canada. Tamara.Franz-Odendaal@msvu.ca
Summary
The vertebrate ocular skeleton likely originated from a single neural crest module that split early in evolution. This division allowed for independent evolution of its endoskeletal and exoskeletal components.
Area of Science:
- Evolutionary developmental biology (evo-devo)
- Paleontology
- Vertebrate anatomy
Background:
- The origin of the vertebrate ocular skeleton, composed of cartilage and bone, remains unclear.
- Understanding its evolutionary history is crucial for comprehending vertebrate skeletal development.
Purpose of the Study:
- To propose an evo-devo model for the origin and evolution of the vertebrate ocular skeleton.
- To investigate the potential neural crest origin and modularity of ocular skeletal components.
Main Methods:
- Integration of paleontological data with developmental biology findings.
- Comparative analysis of skeletal structures across vertebrate taxa.
Main Results:
- The vertebrate ocular skeleton is proposed to be neural crest-derived.
- A single cranial neural crest module likely divided early in vertebrate evolution into endoskeletal and exoskeletal components.
- These components evolved independently after becoming uncoupled, with the endoskeletal part likely preceding the exoskeletal part.
Conclusions:
- The study offers insights into the evolutionary trajectory of the ocular skeleton.
- Modularity and developmental processes are key to understanding the diversification of this vertebrate structure.
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