Here are a couple of links to articles that you might find interesting. Reference #1 posits that the evolutionary precusor to crystallins (a transparent protein that comprises the lens) occurred in sea squirts (Ciona). Reference #2 provides a review of how the crystallins evolved into two super families are kinds that we see today.

1. https://pubmed.ncbi.nlm.nih.gov/16169492/
2. https://pubmed.ncbi.nlm.nih.gov/23389822/