Invertebrates constitute a vast array of living organisms ranging from the simplest unicellular eukaryotes such as Paramecium to such complex multicellular animals as the octopus, lobster and dragonfly.
ɪnvˈɜːɾɪbɹˌeɪts kˈɑːnstɪtˌuːt ɐ vˈæst ɚɹˈeɪ ʌv lˈɪvɪŋ ˈɔːɹɡənˌɪzəmz ɹˈeɪndʒɪŋ fɹʌmðə sˈɪmpəlɪst jˌuːnɪsˈɛljʊlɚ jˈuːkɐɹɪˌoʊts sˈʌtʃ ɐz pˌæɹəmˈiːsiəm tə sˈʌtʃ kˈɑːmplɛks mˌʌltɪsˈɛljʊlɚɹ ˈænɪməlz æz ðɪ ˈɑːktəpəs, lˈɑːbstɚɹ ænd dɹˈæɡənflˌaɪ.