Related Experiment Video
Updated: Jul 10, 2026

4-Dimensional Imaging of Zebrafish Optic Cup Morphogenesis
Published on: May 26, 2021
Evolution of the vertebrate eye: opsins, photoreceptors, retina and eye cup
Trevor D Lamb1, Shaun P Collin, Edward N Pugh
1Australian National University, Division of Neuroscience, The John Curtin School of Medical Research, Garran Road, The Australian National University, Canberra, Australian Capital Territory 2600, Australia. Trevor.Lamb@anu.edu.au
Abstract:
Charles Darwin appreciated the conceptual difficulty in accepting that an organ as wonderful as the vertebrate eye could have evolved through natural selection. He reasoned that if appropriate gradations could be found that were useful to the animal and were inherited, then the apparent difficulty would be overcome. Here, we review a wide range of findings that capture glimpses of the gradations that appear to have occurred during eye evolution, and provide a scenario for the unseen steps that have led to the emergence of the vertebrate eye.
Related Concept Videos
Anatomy of the Eyeball
Photoreceptors and Visual Pathways
Vision
The Retina
Accessory Structures of the Eye
Gene Duplication and Divergence
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.

