Final answer:
Animals with a dorsal hollow nerve cord and pharyngeal slits during development are called chordates. Humans are indeed chordates and possess these features during embryonic development. Vertebrates form around the notochord, which is replaced by the vertebral column as they mature.
Step-by-step explanation:
Animals with a nerve cord along the back (dorsal hollow nerve cord) and gill slits (pharyngeal slits) during some stage of development are called chordates. This definition includes a diverse group of animals, ranging from fish and amphibians to reptiles, birds, mammals, and humans. Contrary to the incorrect statement that 'humans are not chordates because humans do not have a tail,' humans are indeed chordates. Humans, like all vertebrates, also have a notochord during their embryonic development, which is eventually replaced by the vertebral column as they mature. The pharyngeal slits may not develop into functional gills in humans and many other chordates, but their embryonic presence is still a characteristic feature of the phylum.
Moreover, the dorsal hollow nerve cord develops from the ectoderm and is a significant part of the central nervous system in chordates. The nerve cord is dorsal to the notochord, another distinguishing feature of chordates, which provides structural support during development. Vertebrates, a subcategory of chordates, initially form the vertebrae around the embryonic notochord, but the notochord is later replaced by the vertebral column in adults.