Briefly describe the ‘suites of developmental characteristics’ that characterize protostomes and deuterostomes, respectively. Why are developmental features so fundamental to taxonomic classification compared to other prominent anatomical and physiological adult features?  Why are development (ontogeny) and evolution (phylogeny) so closely linked together? Explain the fundamental relationship between organic evolution and embryonic development.  Describe how one is linked to the other in terms of mechanisms and hierarchical level of action.  Please include both the terms 'genotype' and 'phenotype' in your answer Is it accurate to state that ontogeny recapitulates phylogeny? Explain.  Why does mammalian embryonic development resemble that of birds and reptiles, when mammals do not develop in shelled yolky eggs?