sentence2_structure: Invertebrates (and higher animals<>can be placed<>$$$two groups<>based<>on how they develop as embryos$$$they<>develop<>
sentence1: In the procedure, one or two cells can be removed from an IVF embryo at the 8- to 16-cell stage for biopsy, without affecting subsequent development of the embryo.
sentence2: Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as embryos.
question: Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as what?