According to the geologic time scale, in what era did most types of animals first appear

In the geological time period, the appearance of the majority of the present known animals and species took place during the Cambrian period of Paleozoic era,  The first phylum, which appeared during this period were the Chordates along with various other different species of animals like brachiopods, archaeocyatha, pirapulid, trilobite, sponges, and others.  

The prokaryotes, fungi, protists, and algae that originated during this era are still modifying and developing at the present time.  

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explanation: