Evolution from Amphibians to Birds and Mammals and the Abrupt Cessation of Nature’s Experiment at the Reptilian Stage

  • Susumu Ohno


In Table 5, frogs and toads of the order Anura (descendants of the main labyrinthodont lineage of early amphibians) are compared to salamanders and newts of Urodela (lepospondyls side branch). It immediately becomes clear that their genomes reflect the fact that the two belong to different lineages.


Genome Size Tandem Duplication Placental Mammal Diploid Chromosome Number Genetic Redundancy 
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© Springer Science+Business Media New York 1970

Authors and Affiliations

  • Susumu Ohno
    • 1
  1. 1.Department of BiologyCity of Hope Medical CenterDuarteUSA

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