sˈoʊ, ðɪ ɛkspˈɛktᵻd ˌɛvəlˈuːʃənˌɛɹi hˈɪstɚɹi ɪz ðæt dʒˈiːn dˌuːplɪkˈeɪʃən ʌvðə sˈiːlˈaɪsəzˌaɪm wʌz fˈɑːloʊd baɪ mjuːtˈeɪʃən, ɹɪzˈʌltɪŋ ɪnðə lˈɔs ʌv lˈaɪsəzˌaɪm kˌæɾɐlˈɪɾɪk æktˈɪvᵻɾi ɪn ˈælfəlˈæktɐlbjˌuːmɪn.
So, the expected evolutionary history is that gene duplication of the c-lysozyme was followed by mutation, resulting in the loss of lysozyme catalytic activity in α-lactalbumin.