During devonian time life transitioned to land. two major divisions of animals moved ashore, first the arthropods and then the tetrapod vertebrates. what fossil evidence best supports the classification of animals into these two basic branches, still recognized today? a)fossilized amniotic eggs b)impressions of scales versus fur eliminatec)evidence of exoskeletons and endoskeletons d)fossilized bones with and without air cavities     d)fossilized bones with and without air cavities

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.