Visual gene expression reveals a cone to rod developmental progression in deep-sea fishes

To investigate whether the retinal development in deep-sea fishes follows a similar cone-to-rod molecular pathway as found in other vertebrates or whether some species start their lives with the rod pathway activated, we set out to sequence the retinal transcriptomes of 20 deep-sea fish species, including the larval stages in ten species, belonging to eight different teleost orders (Argentiniformes, Aulopiformes, Beryciformes, Myctophiformes, Pempheriformes, Scombriformes, Stomiiformes and Trachichthyiformes).