Answer:
2.Vertebrates originated about 525 million years ago during the Cambrian explosion, which saw rise in organism diversity. The earliest known vertebrate is believed to be Myllokunmingia. One of many early vertebrates are Haikouichthys ercaicunensis.
3. As chordates, vertebrates have the same common features: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. Vertebrates are further differentiated from chordates by their vertebral column, which forms when their notochord develops into the column of bony vertebrae separated by discs.
4.The bones of the vertebrate skull protect the brain. In the more advanced vertebrates and invertebrates, many skeletal structures provide a rigid base for the insertion of muscles as well as providing protection. The skeleton facilitates movement in a variety of ways, depending on the nature of the animal.
5.Vertebrates reproduce sexually, and almost all of them have separate male and female sexes. Recall that sexual reproduction is the joining of gametes during fertilization, producing genetically variable offspring. ... Vertebrates have one of the following three reproductive strategies: ovipary, ovovivipary, or vivipary.
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