is there a sentence fragment? during the precambrian period, most of earths life forms lived in oceans…

is there a sentence fragment? during the precambrian period, most of earths life forms lived in oceans. meanwhile, land masses were mostly devoid of life. yes no
Answer
Brief Explanations:
The text consists of two complete sentences. Each has a subject and a predicate. There are no sentence - fragments.
Answer:
no