Invertebrates (and higher animals<>can be placed<>$$$two groups<>based<>on how they develop as embryos$$$they<>develop<>
Because of the way the eggs develop, parthenogenetic embryos have only one type of sex chromosome, and of the two possibilities only ZZ embryos can survive.
Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as embryos.
Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as what?