During the Iron Age about 2,500 B.P., relatively young Austroasiatic branches in Indochina such as Vietic, Katuic, Pearic, and Khmer were formed, while the more internally diverse Bahnaric branch (dating to about 3,000 B.P.) underwent more extensive internal diversification.
dˈʊɹɹɪŋ ðɪ ˈaɪɚn ˈeɪdʒ ɐbˌaʊt tˈuː,fˈaɪvhˈʌndɹɪd bˈiː.pˈiː., ɹˈɛlətˌɪvli jˈʌŋ ˌɔːstɹoʊsɪˈæɾɪk bɹˈæntʃᵻz ɪn ˌɪndoʊtʃˈaɪnə sˈʌtʃ ɐz vˈiːətˈɪk, kætˈuːɪk, pˈɪɹɪk, ænd kmˈɪɹ wɜː fˈɔːɹmd, wˌaɪl ðə mˈoːɹ ɪntˈɜːnəli daɪvˈɜːs bɑːnˈæɹɪk bɹˈæntʃ dˈeɪɾɪŋ tʊ ɐbˌaʊt θɹˈiː,zˈiəɹoʊzˈiəɹoʊ zˈiəɹoʊ bˈiː.pˈiː.ˌʌndɚwˈɛnt mˈoːɹ ɛkstˈɛnsɪv ɪntˈɜːnəl daɪvˌɜːsɪfɪkˈeɪʃən.