Abstract of Smith, G.R. 1992. Introgression in fishes: Significance for paleontology, cladistics, and evolutionary rates. Syst. Biol. 41(1):41-57.

  • Introgression in fishes results in comb-shaped cladograms and loss of evolutionary history. The pink and chum salmon have exchanged mitochondrial genomes during their evolution, leading to erroneous molecular cladograms and serious underestimates of divergence times. There are a few examples of fossil hybrid fishes.