Complex sentence: Similar darkness-adaptive traits can be seen in fish families in other types of isolated environments in a manifestation known as convergent evolution, and has been observed in the Characidae, Cyprinidae, Eleotridae, Gobiidae, Poeciliidae, Siluriformes, Synbranchidae, and various other families.
Split into simpler sentences: Similar darkness-adaptive traits can be seen in fish families in other types of isolated environments. This is a manifestation of the phenomenon known as convergent evolution, and has been observed in Characidae, Cyprinidae, Eleotridae, Gobiidae, Poeciliidae, Siluriformes, Synbranchidae, and various other families.