The cross-breeders

Sometimes it’s the fish themselves that seek to complicate matters. A study published last year in the Proceedings of the Royal Society journal reported occurrences of hybridisation involving 42 species of marine angelfish family. For context, this involved all but one genus and accounted for 48% of all species within the family. While crowded coral reefs act as hybrid zones, facilitating these interspecies breeding events, this tendency for hybridisation is still far higher than expected.