Modern amphibians have a simplified anatomy compared to their ancestors due to paedomorphosis, caused by two evolutionary trends: miniaturization and an unusually large genome, which result in a slower growth and development rate compared to other vertebrates.
mˈɑːdɚn æmfˈɪbiənz hæv ɐ sˈɪmplᵻfˌaɪd ɐnˈæɾəmi kəmpˈɛɹd tə ðɛɹ ˈænsɛstɚz dˈuː tə pˌiːdəmˈoːɹfəsˌɪs, kˈɔːzd baɪ tˈuː ˌɛvəlˈuːʃənˌɛɹi tɹˈɛndz: mˌɪnɪtʃɚɹᵻzˈeɪʃən ænd ɐn ʌnjˈuːʒuːəli lˈɑːɹdʒ dʒˈiːnoʊm, wˌɪtʃ ɹɪzˈʌlt ɪn ɐ slˈoʊɚ ɡɹˈoʊθ ænd dɪvˈɛləpmənt ɹˈeɪt kəmpˈɛɹd tʊ ˈʌðɚ vˈɜːɾɪbɹˌeɪts.