what are the two most important events in the history of animal life that occurred at the beginning and at the end of the Paleozoic era?

Answer 1

he Paleozoic is bracketed by two of the most important events in the history of animal life. At its beginning, multicelled animals underwent a dramatic "explosion" in diversity, and almost all living animal phyla appeared within a few millions of years. At the other end of the Paleozoic, the largest mass extinction in history wiped out approximately 90% of all marine animal species.

Answer 2

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