haʊˈɛvɚ, ðɪ ˌɛvəlˈuːʃənˌɛɹi hˈɪstɚɹi bˈoʊθ ʌvðɪ ɪmˈɜːdʒəns ʌv mˈɑːlʌsks fɹʌmðɪ ænsˈɛstɹəl ɡɹˈuːp lˌɑːfətɹˌoʊkəzˈoʊə, ænd ʌv ðɛɹ daɪvˌɜːsɪfɪkˈeɪʃən ˌɪntʊ ðə wˈɛlnˈoʊn lˈɪvɪŋ ænd fˈɑːsəl fˈɔːɹmz, ɪz stˈɪl vˈɪɡɚɹəsli dᵻbˈeɪɾᵻd.
However, the evolutionary history both of the emergence of molluscs from the ancestral group Lophotrochozoa, and of their diversification into the well-known living and fossil forms, is still vigorously debated.