Scaled, armoured or naked: how does the skin of fish evolve?

Usually scaled, the skin of fish can also be naked or made up of bony plates that form an armour, sometimes even covered with teeth. But how has this skin evolved over the ages? To answer this question, Alexandre Lemopoulos and Juan Montoya have reconstructed the evolution of the protective skin structures in fish, going back to the common ancestor of ray-finned fish, more than 420 million years ago. They found that only fish that had lost their scales were able to develop a bony armour, and that the protective state of their skin influenced their choice of open water or sea floor habitats. This study, published in the journal Evolution Letters, provides a new explanation for the incredible diversity of this lineage of fish, which includes more than 25,000 species.

The article was published in Evolution letters on March 23rd, 2021.

Press release

This study is also covered by other media :

La perte d’écailles chez certains poissons, une histoire d’habitat Sciences et Avenir, 30.03.2021