tˈaɪloʊsfˌeɪl haʊˈɛvɚ, ɐ tˈuː θˈaʊzənd twˈɛnti klædˈɪstɪk ɐnˈæləsˌɪs ɹᵻkˈʌvɚd ðə hˌɛɾɚɹˌoʊdɔntəsˈɔːɹɪdz æz ɐn ˈɜːli bɹˈæntʃ ʌvðə ɡɹˈuːp, wˌɪtʃ ɛkstˈɛnd ðɪ ˈeɪdʒ ʌv pˌækɪsɪfˈæləsˌɔːɹz æz fˈɑːɹ bˈæk æz ðɪ ˈɜːli dʒjʊɹɹˈæsɪk.
Tylocephale However, a 2020 cladistic analysis recovered the heterodontosaurids as an early branch of the group, which extend the age of pachycephalosaurs as far back as the Early Jurassic.